Late Early Devonian ostracodes from the Torkoz area (SW Morocco) and the Emsian/Eifelian boundary

A new rich and diversified ostracode fauna from the Torkoz area (section Hassi Mouf South, Moroccan Anti-Atlas) is described and the ostracode distribution near the Early/Middle Devonian boundary is discussed. This ostracode fauna of a single limestone bed yields 32 taxa and is compared with the less-diversified ostracode fauna from an adjacent parallel section Hassi Mouf South as well as with a published conodont-bearing sample from section Torkoz. All three ostracode faunas are closely related, and therefore, the same latest Emsian age is postulated. Palynomorphs (acritarchs and prasinophytes) from section Torkoz support this late Early Devonian age and the scarce brachiopod fauna of the equivalent level from section Hassi Mouf South suggests a stratigraphical position very close to the Emsian/Eifelian boundary, probably latest Emsian. Zygobeyrichiasubcylindrica from a thin marly bed embedded in shales, slightly below the ostracode-rich sample from section Hassi Mouf South, and the conodonts of the patulus Zone from section Torkoz, favours the position of the Early/Middle Devonian boundary within the Yeraifia Formation and not in or on top of the Rich 4 Sandstone in the SW Dra Valley area as hitherto published. The latest Early Devonian ostracode faunas from the Torkoz area belong to the shallow-water Eifelian Ecotype of G. Becker. The new genus Karlingrella for Euglyphella? granulosa Blumenstengel, 1962 and the new species Quasillites (Beckjennites) gebeckeri are erected.


Introduction and geological setting (R. T. Becker, E. Schindler and H. Groos-Uffenorde)
The Devonian of the Anti-Atlas of southern Morocco is world-famous for its extensive outcrops incredibly rich in well-preserved faunas. Detailed investigations of Devonian stratigraphy in the Dra Valley (southwestern Anti-Atlas) began with Hollard and Jaquemont (1956), followed by a large number of specialised publications mainly by H. Hollard (see reference lists, e.g., in Bultynck and Hollard 1980;Bultyck and Walliser 2000;Jansen 2001).
More recent overviews of the Dra Valley stratigraphy, including many new palaeontological data, and with introduction of new lithological units, were given by R.T. Becker et al. (2004c) and Jansen et al. (2007). Sedimentological compilations and sequence stratigraphic aspects were published by Ouanaimi and Lazreq (2008) and Lubeseder et al. (2009). A first brief record of the succession at section Hassi Mouf South was published by Baird et al. (2009), with 1 3 additional details in DeSantis and Brett (2011) shown for comparison in Fig. 2, section Hassi Mouf gully.
Recently, many sections in the Dra Valley region were studied by research groups from the University of Münster and the Senckenberg Research Institute Frankfurt. Some of the conodont samples from sections Bou Tserfine, Rich Tamelougou, and Hassi Mouf South in the Dra Valley south of the village of Aouinet Torkoz yielded late Early Devonian to early Middle Devonian age ostracodes, which will be described in a forthcoming publication by Dojen et al. Only the latest Early Devonian ostracodes of the Torkoz area are described in the present paper. Figure 1 shows the studied localities in the Torkoz area north of the Dra valley in southwestern Morocco and Fig. 2 shows the different sections in this area as named by different authors.
The complete section Hassi Mouf South ranging from the late Emsian Rich 4 Sandstone Member to the early Givetian was discovered by students from Münster University mapping in the Hassi Mouf area ca 10 km SSE of Aouinet Torkoz (Fig. 1), whereas the Senckenberg group sampled together with, e.g., G. Baird during a bilateral US-German National Geographic project in 2007 only in Early/Middle Devonian boundary beds (Crinoid Marl Member of the lower Yeraifa Formation above the Rich 4 Sandstone of the upper Khebchia Formation). In Fig. 2, this section is cited as Torkoz 5 according to the figured section in an e-mail of G. Baird (State University of New York at Fredonia, NY) from 28 November 2014, but cited in the systematics as Hassi Mouf South according to Baird et al. (2009).
The ostracodes described in the systematic part have been found in a thin calcareous siltstone intercalation (sample FRA-TKZ 4 with many large Zygobeyrichia valves, first cited as shell lags with macrofauna and 'large, distinctive ostracodes' in Baird et al. 2009, but not marked in the section Hassi Mouf South of the Münster group in Fig. 2) some tens of metres above the top of the Rich 4 Sandstone Member and only a few decimetres below a distinct limestone bed. This limestone bed characterising the base of the onset of limestone intercalations of the section Torkoz 5 (e-mail by G. Baird 2014) resp. Hassi Mouf-South of Baird et al. (2009) contained the diversified ostracode fauna of sample FRA-TKZ 4c2 (see Fig. 2). The age of these ostracode faunas together with the conodont determination by K. Weddige (Frankfurt) is discussed below under the subsequent heading 'Stratigraphy of the ostracodes of the Torkoz area'. Their correlation with sample Tor Eif/2d from the detailed section Hassi Mouf South of the Münster group and with the section Torkoz II sensu G. Becker et al. (2004)  towards the west is shown in Figs. 2 and 19. The ostracodes from the overlying Middle Devonian Pinacites Limestone, as well as from the underlying Early Devonian (e.g., Hollardops Limestone) will be included in a planned paper by Dojen et al. mentioned above.

Sedimentology and facies (E. Schindler)
Two samples are described concerning their sedimentology, facies, and faunal content (Fig. 3); sample FRA-TKZ 4c2 from the section Hassi Mouf South (sensu written communication G. Baird 2014) and sample Tor Eif/2d from the section Hassi Mouf South of R.T.B. (for detailed explanation, see previous section and Fig. 2). Sample FRA-TKZ 4 situated slightly below sample FRA-TKZ 4c2 is less calcareous and no thin sections were studied. This thin fossiliferous layer is hitherto not described from other sections.

Sample FRA-TKZ 4c2, section Hassi Mouf South
The (partly) sparitic appearance of the ostracode-rich bed is mainly due to the presence of large amounts of echinoderm fragments (mainly crinoid ossicles including longer stem fragments, but also other echinoderms). Some of the crinoid ossicles are oval and some are heavily corroded. The arrangement of most of the debris is chaotic with bedding indicated by the alignment of platy brachiopod shells For the position of the sections, see Fig. 1, and for details of the ostracode samples, see 'Introduction to the material', Section Hassi Mouf South: Complete section from the late Emsian Rich 4 Sandstone Member to the early Givetian (measured by the Münster University group)-with sample Tor Eif/2d (here shortened to Eif/2d). Section Torkoz 5 (named as such only by Baird in 2007 and in an e-mail 2014 changed to Hassi Mouf South by Baird et al. 2009) few metres lateral to the section Hassi Mouf South with samples FRA-TKZ 4 and FRA-TKZ 4c2 (collected by the Senckenberg group). The locality of these two samples is cited in the entire paper as Hassi Mouf South. The complete Eifelian section Hassi Mouf gully is included for comparison (no samples studied). Section Torkoz IIa and Torkoz Giv (sensu G. Becker et al. 2004) farther to the west show a sampling gap near the Early/Middle Devonian boundary and other elongate fossils (best seen in the polished slab on Fig. 3a). Also present are randomly distributed fine-grained extra-clasts of siliciclastic material (right part of Fig. 3a and subsequent close ups).
Besides the dominance of echinoderms, the fossil content yields a number of bryozoans, which are also visible on bedding planes of smaller pieces of the bed (Fig. 3f). Also present-but in smaller numbers-are trilobite fragments (e.g., arrows in Fig. 3d). Striking fossils are punctate shells of brachiopods (with very densely spaced puncta) which are most probably arranged according to bedding (frequently visible in Fig. 3a-e). Other brachiopods (mostly smaller fragments of ribbed forms) are present, but in restricted numbers (e.g., in Fig . Although the conodont sample residue yields a great variety of ostracode taxa, they are hardly visible in the polished slab or in the thin section. This may be due to sporadic occurrence with eventual accumulations in "pockets".
The observations from a polished slab as well as from a thin section indicate agitated water. The ostracode-rich bed represents a relatively high-energy deposit and can be described as crinoid-debris limestone.

Sample Tor Eif/2d, section Hassi Mouf South
At first glance, the polished slab of sample Tor Eif/2d looks rather different from that of bed FRA-TKZ 4c2, but there are some similarities present ( Fig. 3g-h). The bed also represents a debris limestone, deposited in shallow agitated water. The number of fossils is even higher. Crinoid ossicles (some still attached to each other forming longer stem fragments) are also frequent; some show selective corrosion (blue "c" in Fig. 3g,central part). Amongst the brachiopods, the same punctate shells are present comparable to those in sample FRA-TKZ 4c2. However, there are more of other brachiopods, in many cases with relatively large and smooth shells (blue "sb" in Fig. 3g, h). Also, similar are numerous bryozoan specimens (at least as many as in sample FRA-TKZ 4c2, but even more diverse) of which some are quite long (up to 2 cm). Trilobites are also present, in even higher numbers, and the specimens are mostly somewhat bigger (roughly twice the size).
Although we did not find so many ostracode specimens/ taxa in this bed comparable to sample FRA-TKZ 4c2, the polished slab seems to show some questionable ostracode valves (o in Fig. 3h). The shells are perhaps better visible because of different shell material due to reduced ore even missing recrystallisation. Besides such small shells, there are higher numbers of other shells of unknown organisms. Some small circular fossils (cross-sections showing crystals inside) of unknown origin (? spines) are present (frequently visible in Fig. 3g, h).
The slightly different character and greater thickness of this bed compared to that of sample FRA-TKZ 4c2 (somewhat different distribution of the main fossil content, bedding not recognisable) may indicate a facies change, i.e., from a relatively thick limestone bed (Tor Eif/2d) to a more shaly/marly succession with thin intercalated limestone beds (FRA-TKZ 4c2).   (for explanation see text). a SMF 99517, polished and etched slab; crinoid-debris limestone, bedding is indicated by aligned platy brachiopod shells and longer fragments of crinoid stems; b close-up of a, image slightly rotated; big corroded crinoid ossicle and punctate brachiopod shell clearly visible; c another close-up of a, image slightly rotated; slim punctate brachiopod shell and corroded fragment of crinoid stem (aligned); d SMF 99518, thin section with siliciclastic "pockets" (left and upper right), corroded fragment of crinoid stems (central upper part), punctate brachiopod shells (lower left), and small trilobite fragments (arrows near top); e close-up of d; crinoid stem fragment and punctate brachiopod shell, both corroded; f SMF 99,519, bed surface with different bryozoans; g SMF 99520, polished and etched slab; crinoid-debris limestone, with numerous fossils: corroded fragments of crinoid stems (c), punctate brachiopod shells (pb)-as in sample FRA-TKZ 4c2, other brachiopod shells (sb)-often smooth shells, more trilobite fragments (and bigger) than in sample FRA-TKZ 4c2 (t) and a number of (different) bryozoans (b); note that punctate brachiopod shells are somewhat thinner than in sample FRA-TKZ 4c2; h close-up of g; with long bryozoan longitudinal section (upper left) and cross-sections (lower centre and near right edge), corroded fragment of crinoid stem, punctate brachiopod shell and shells (mostly smooth) of other brachiopods, big trilobite-in the upper part questionable ostracode valves (o) visible ◂ More than 500 silicified ostracodes (the geochemical composition of the ostracode valves has not been analysed) of sample FRA-TKZ 4c2 were picked and described from a large conodont sample residue of a coarse-grained crinoidal limestone at the base of the fossiliferous limestones and calcareous shales of the Crinoid Marl Member. The rock sample was prepared by standard conodont preparation techniques and a lot of the residue is available for further studies.

Introduction to the material
The preservation of the ostracodes (mostly single valves and rare carapaces) varies greatly. Some ostracodes have excellent preservation because of fine-grained recrystallization, but others are poor and often damaged, because of coarse-grained recrystallisation. The latter specimens were, of course, less resistant during the conodont sample processing.
In contrast, the calcareous ostracode valves of the unprocessed sample FRA-TKZ 4 are preserved on slabs of a thin calcareous intercalation near the top of the argillaceous basal Yeraifa Formation. Besides very few small non-beyrichiacean ostracodes, e.g., Bollia and Jenningsina, the bedding planes are crowded with large Zygobeyrichia valves (see Fig. 4).
Some silicified ostracodes of sample Tor Eif/2d (residue of conodont sample of R.T.B. poor in ostracodes) from the same basal limestone bed in section Hassi Mouf South are cited for comparison. A detailed description will be included in the forthcoming paper of Dojen et al. Remarks on the brachiopod fauna from this sample are given by U.J.
Silicified ostracodes of sample Torkoz Giv 1 sensu G. Becker et al. (2004) from the Torkoz section at Rich Tamelougou in the north of the Dra Valley, south of Aouinet Torkoz (Fig. 1), are also discussed. In the following text, the material of G. Becker et al. (2004) from the Torkoz section is cited as sample Giv 1B and additional material picked from the remaining conodont sample residue of K. Weddige is cited as sample GIV 1 W. Remarks on palynomorphs from this sample are given by R. B.
The material is deposited in the collections of the Senckenberg Research Institute Frankfurt. The ostracodes are cited under the SMF Xe numbers, palynomorphs under the cited SMF PMP numbers, brachiopods, and sedimentology/facies samples under the cited SMF numbers.

Remarks on the systematic nomenclature
According to the glossary of the fourth edition of the ICZN 1999, the ending of the Palaeozoic ostracode 'superfamilies has the suffix-OIDEA ', which is a change from the traditionally used ending -acea into -oidea. We think that there is no need to change the traditionally used names only to unify Palaeozoic and post-Palaeozoic nomenclature without any new interpretations or new results or knowledge. Instead, we want to avoid misunderstandings in using the important international literature of the former centuries. Therefore, we prefer, like many colleagues working in the Palaeozoic (e.g., G. Becker 2002, G. Becker 2003Dojen 2005;Kornicker and Sohn 2000;Nazik and Groos-Uffenorde 2016;Perrier et al. 2011;Wang 2009), the traditional and undisputed name-e.g., Beyrichiacea instead of Beyrichioidea. We follow the unanimous decision after discussions during the ISO Meetings (International Symposia on Ostracoda, e.g., in Houston 1982) and not the unified ending of the superfamily names proposed by the International Commission on Zoological Nomenclature (ICZN effect from 1 January 2000).

Abbreviations in the nomenclature
cf.-Exact species determination not possible because of slightly differing features aff.-Taxon differing from the cited species but related to it sp.-Sparse material or poorly preserved ? in front of a genus name-Definition or classification questionable ? behind a genus name-Doubtful determination, often because of obscure definition ? behind a species name-Identification uncertain often because of poor preservation gr. (group)-Taxa with great variation, no delimitation or exact determination possible vel (latin, 'or')-No delimitation between two taxa possible TKZ-Torkoz area, samples FRA-TKZ GIV-Section Torkoz Giv sensu G. Becker et al. (2004) Abbreviations in the descriptions L-Length H-Height W-Width, thickness of carapace lv-Left valve rv-Right valve DR-Dorsal border VR-Ventral border L 1 -Praesulcal/anterior lobe or node L 2 -Postsulcal lobe or node L v -Ventral lobe (e.g., ventral connection L 1_ L 4 ) zygal ridge (e.g., in Bolliidae)-Ventral connection of L 1 and L 2 S-Sulcus S 2 -Adductorial sulcus Stk-Steinkern, internal mould het.-Heteromorph, presumably female tecn.-Tecnomorph, presumably male or juvenile (= juv.)
Important diagnostic features. Large trilobate beyrichiacean ostracodes, according to Ulrich (1916) characterised by a varying distinctness of a ventral connection of L 1 and L 2 (zygal ridge). In contrast to Gibba Fuchs, 1919, the tecnomorphs do not have an alate structure.
Occurrence. Zygobeyrichia subcylindrica is often reported from the European late Early Emsian to latest Emsian. External and internal moulds are common and widespread in the Emsian shales and siltstones of Germany (see Groos-Uffenorde 1982: pl. 3 fig. 19 and discussion in G. Becker and Bolz 1991 Baird et al. (2009: p. 193) as 'large, distinctive ostracodes'. The specimens are often incomplete, internal views of heteromorph and tecnomorph valves mostly covered with sediment.
Important diagnostic feature. Large beyrichiacean ostracodes with straight L 1 , relatively long and anteroventrally pointed and not connected with L 2 or L 3 ; L 2 distinct, elongate and ventrally pointed (but without tubercle or carina like Gibba or Carinokloedenia Abushik 1971); L 3 large but less distinct, ventrally connected with an indistinct ventral lobe, but ventrally not distinctly connected with L 2 as in the  Richter, 1863) on bedding planes with crinoids, sample FRA-TKZ 4, section Hassi Mouf South. a SMF Xe 23497, part of the bedding plane of slab A; b SMF Xe 23500, bedding plane of slab D; c SMF Xe 23497a, detail of slab A, L = > 4.3 mm, interior view of tecnomorph rv of Zygobeyrichia, besides SMF Xe 23497b, L = 1.3 mm, exterior view of Bollia sp.; d SMF Xe 23500a, detail of slab D, L = 4.6 mm, inte-rior view of a heteromorph rv; e-g SMF Xe 23501a, detail of slab E, L = > 3.5 mm, posteriorly slightly incomplete tecnomorph lv; e slightly tilted lateral view; f dorsal view and g anterior view; h SMF Xe 23498 = bedding plain of slab B; i SMF Xe 23501, bedding plane of slab E; j SMF Xe 23500, bedding plane of slab D; k SMF Xe 23,499, bedding plane of slab C American genus type material. The anteroventral crumina of the heteromorphs is not clearly separated from the lateral surface. The row of marginal tubercles ('kurze Randborsten') described by Spriestersbach (1925: p. 400) is hard to be seen at calcareous valves in contrast to the better preservation on external moulds. The outline and lobation is comparable to Zygobeyrichia devonica of Spriestersbach (1925: fig. 2) from the late Early Devonian of Germany.
Remarks. In contrast to the European Zygobeyrichia subcylindrica, the Moroccan material does not clearly show the characteristic tubercle on the L 2 . This tubercle is best seen on external moulds in the German material, but in general, the internal views of the shell or internal moulds do not show this tubercle. The L 2 is bulbous and not elongate as in the Moroccan material.
There are close relations to Zygobeyrichia devonica (Jones and Woodward, 1889) sensu Spriestersbach 1925 (but not sensu Jones!) and Zygobeyrichia subcylindrica (Rh. Richter, 1863), but it has still to be verified if both species are conspecific.
G. Becker and Franke (2012: p. 96, pl. 7, fig. 6) figured a ventral view of a tecnomorph Zygobeyrichia sp. W, ex gr. Z. subcylindrica with distinctly pointed end of the L 1 comparable to Turkish material (Nazik and Groos-Uffenorde 2016: p. 208, fig. 7.4 named Gibba ? sp., aff. kayseri) characterised by a subdivided L 1 instead of the subdivided L 3 in Gibba ? kayseri. Because of the long S 2, the Luxemburg material clearly belongs to Zygobeyrichia. Tecnomorphs of G. ? kayseri are still unknown and an exact genus determination is not possible.
Occurrence. Known only from the Torkoz area, SW Morocco.
Superfamily Hollinacea Swartz, 1936 Family Ctenoloculinidae Jaanusson andMartinsson, 1956 Genus Ctenoloculina Bassler, 1941 Type species. Tetradella cicatricosa Warthin, 1934 Remarks. This quadrilobate genus is characterised by a pronounced locular dimorphism. The species are mainly separated by the difference in the shape of the lobation and velar structure. Zagora, 1968Figure 5a-g *1968  Important diagnostic features. Most important are the ventral parts of the lobes: only the broader L 3 of the heteromorphs is isolated from the adventral structure ('Velum'), but the L 1 and L 2 are connected with the adventral structure. The lobes do not overreach the dorsal margin. A row of tubercles is visible in the prolongation of the adventral structure. The heteromorph valves have 6 loculi. The sulci are narrow.

Ctenoloculina disjuncta
Remarks. Ctenoloculina similidisjuncta Becker n.sp. in G. Becker et al. (2004) is characterised by lobes overreaching the dorsal border, and L 2 and L 3 are not connected with the adventral structure. The heteromorph valves show only 5 instead of 6 loculi.
The lobation of C. latisulcata Adamczak, 1968 (Grzegorzowice beds of the Holy Cross Mountains, Poland) is very similar, but the sulci are broader.
All lobes (L 1 , L 2 , and L 3 ) are isolated and separated from the adventral structure in C. vulgaris Adamczak, 1968 from the Skaly beds, Eifelian of the Holy Cross Mountains, Poland.
Within C. skalyensis Adamczak, 1968, also from the Skaly beds, the L 2 and L 3 are only partly separated from the adventral structure.

Ctenoloculina latisulcata
Remarks. The heteromorph valves have 6 loculi comparable to Ctenoloculina disjuncta in contrast to the 5 loculi of C. similidisjuncta Becker, 2004n.sp. in G. Becker et al. (2004. The lobation of C. disjuncta is very similar, but their sulci are narrow. Occurrence. Latest Emsian (Early Devonian) and earliest Eifelian (Middle Devonian. The early Middle Devonian age of the Grzegorzowice beds of the Holy Cross Mountains, Poland was changed by conodonts as latest Emsian by Malec and Turnau (1997). G. Becker et al. (2004) cited Middle Devonian specimens from the Torkoz area and figured on pl. 6, fig. 10 one heteromorph valve from Torkoz GIV 1 (= Giv 1B); this sample is dated as latest Emsian in the paper in hand. Ostracodes from the uppermost Büyükdere section of the western Pontides, NW Turkey in Olempska et al. (2015) were dated as earliest Middle Devonian.
Remarks. Because of lack of heteromorph specimens, a precise determination is not possible. The narrow sulci of the specimen from GIV 1 W are comparable to those of C. disjuncta but the shape of the lobes resembles those of C. cicatricosa sensu Zagora, 1968 from the Late Emsian of Germany (Tentaculitenschiefer of Thuringia).
Remarks. The tecnomorph rv with granulose surface from sample Torkoz GIV 1 W may belong to Parabolbina kroemmelbeini Zagora, 1968, but parts of the adventral structure are incomplete. The lateral spine of the second tecnomorph rv from sample FRA-TKZ 4c2 is more distinct compared with the specimen from Torkoz GIV 1 W, but incomplete posteriorly and resembles Parabolbina sp. sensu Zagora, 1968.
Occurrences. Pragian to Emsian of Europe and North Africa, but not cited from the Torkoz area. The doubtful occurrence in the Eifelian of Algeria is not mentioned in the revision of Maillet et al. (2013). Remarks. Becker (G. Becker et al. 2004: p. 26-27) separated B. azagora and B. bezagora, which are age-equivalent and often co-occurring in the same samples, but their discrimination is insufficiently known. An exact discrimination of the new material from Morocco is unsatisfactory because of the great variation in outline, lobation, and ornamentation. Several specimens from the Torkoz area show a reticulated surface with smooth sulci. The separation of the two species in G. Becker et al. (2004a, b, c, d) is not followed because of the very small number of specimens in the material of K. Zagora (1968) and the questionable assignment of Becker (G. Becker et al. 2004: p. 26) of his own material from sample Torkoz Giv 1. Becker, 1996*1996Bollia lavibadia n. sp.-G. Becker: p. 144, figs. 6, 7/3-4. 2005Bollia lavibadia Becker 1996.14, pl. 3, fig. 1 (with synonymy).
Occurrences. Early Devonian. Pragian-early Emsian of Northern Spain and now latest Emsian of Morocco, but not mentioned from Morocco in G. Becker et al. (2004). Remarks. Two different subgenera have been created because of the different outline and the adventral structure: Ulrichia (Ulrichia) Jones, 1890 und Ulrichia (Subulrichia) Abushik, 1971. It has still to be verified if the often simultaneous occurrences of these two subgenera may be interpreted as sexual dimorphism. U. (Ulrichia) is much more common than U. (Subulrichia) in the material of G. Becker et al. (2004). Thus, U. (Ulrichia) could cbe considered as the heteromorph form with the possibility of parthenogenesis. On the other hand, the outline of U. (Subulrichia) matches closely the outline of a typical heteromorph. This problem remains unsolved.
Occurrences. Silurian of Canada and doubtful specimens from Gotland, Sweden; Early and Middle Devonian of Europe and North America. Remarks. The nearly amplete outline and the adventral structure (= velate ridge or adventral ridge) parallel to the free margin differentiates the subgenus from Ulrichia (Subulrichia) Abushik, 1971. It is characterised by a preplete outline and an adventral structure which curves posteroventrally onto the lateral surface.

Remarks.
We consider the European material as a highly varying group closely related to U. spinifera from North America Occurrences. Ostracodes very closely related to the American U. (U.) spinifera are known from the Early to Middle Devonian of Europe, North Africa, and North America, and were reported by G. Becker et al. (2004) from Torkoz GIV 1.
Occurrences. Wide spread in Early and Middle Devonian strata of North America, Europe, and North Africa (Morocco) incl. the Early Devonian of section Torkoz II in G. Becker et al. (2004), but not reported from the latest Early Devonian of the Torkoz area.
Family Aechminidae Bouček, 1936 Genus Remarks. The base of the spine seems to be less pronounced in Aechmina sp. B figured in G. Becker et al. (2004) from Torkoz Giv 1B. The spine is broader and shorter as within Aechmina aff. sp. A sensu Sanchez de Posada, 1977 in G. Becker et al. (2004: p. 32)).
Occurrences. Two left valves from Torkoz Giv 1B (supposed early Eifelian of Morocco in G. Becker et al., 2004), a few valves from Torkoz Giv 16 (early Givetian of Morocco) and questionable specimens from the "Eifelian supérieur" of Ougarta, Algeria (LeFèvre, 1963: pl. 10, fig. 152). In the latest Early Devonian of the Torkoz area, only two specimens have been found in sample Torkoz GIV 1 W and no specimens in sample FRA-TKZ 4c2.
Family Aechminellidae Sohn, 1961 Remarks. This family was placed within the Drepanellacea by Sohn (1991). Because of the probably dimorphic lateral outline, the suborder and superfamily is unknown (Sohn 1975: G4 Important diagnostic features. Small, unrimmed, amplete, trilobate species with elongate, distinct L 2 overreaching the dorsal border. The less-pointed L 1 and L 3 slightly overreaching the DR are ventrally weakly connected. The S 3 parallel to the posterior border is much longer than the short S 2 . The valve surface is reticulated.
Occurrences. The new Moroccan material is the first record in the latest Early Devonian. This genus was hitherto known from the Middle Devonian and has not previously been reported from the Devonian of Morocco.
Richina sp. TKZ Figure 6b Material. Only two rv (SMF Xe 22651 and Xe 23509) with incomplete free margin were found in sample FRA-TKZ 4c2, section Hassi Mouf South.

Important diagnostic features.
Distinctly lobate and reticulated Richina. The anterior lobe is globose with a small tubercle on the top directed anteriorly. The smaller posterior lobe is directed posterodorsally. Both are separated by the deep S 2 above the distinct median protuberance. The surface of the valve Xe 22,651 is reticulated except on the lobes and sulcus; the second rv is less well preserved.
Remarks. The lobation of Richina sp. A sensu G. Becker and Groos-Uffenorde, 1982 is comparable to R. kozlowskii Krandievsky sensu Abushik, 1971, but the reticulated surface is lacking in the latter. The lobation is also similar in R. biconica Abushik, 1968 with a less distinct subcentral protuberance. The reticulated Richina sp. B sensu G. Becker and Groos-Uffenorde, 1982 from the latest Early Devonian Heisdorf Formation of the Eifel area, Germany is very similar, but the lobation is less distinct. The related Richina sp. C sensu G. Becker et al. (2004: p. 31) reported from sample Torkoz Giv 1 seems to have a finer reticulation. Richina sp. M41 sensu Dojen, 2005 (only one coarsely pitted silicified right valve from the Early Emsian of Aragón, Spain) is similar, but the lobes are smaller and S 2 more narrow.
The number of specimens of the species with open nomenclature is too small for an exact delimitation of species including the evaluation of the variation.
Occurrences. All cited occurrences seem to be restricted to the late Early Devonian (Emsian).
Becker (see G. Becker et al. 1995 and discussion in G. Becker et al. 2004: p. 33-34) placed the genus Kirkbyrhiza in the Superfamily Kirkbyacea Ulrich and Bassler characterised by the distinct 'kirkbyan' subcentral muscle pit within the nonsulcated family Arcyzonidae Kesling.

Important diagnostic features.
Coarsely reticulated surface around an elongate distinct muscle pit below an indistinct S 2 . The outline and the ornamentation clearly vary. The arrangement of the reticulae may be in rows (parallel to the anterior, ventral, and posterior margins), irregular or with intermediate ornamentation (= indistinct rows). The reticulation is coarser and the sulcation more distinct in juvenile specimens.
Remarks. The valve orientation differs in the literature; according to K. Zagora (1968: pl. 4, fig. 16a), the greatest height is anterior, whereas the right valve of the holotype (refigured in G. Becker et al. 2004: pl. 7, fig. 10) shows a central muscle pit and a higher posterior end. The specimen SMF Xe 22783 from sample FRA-TKZ 4c2 closely resembles the holotype from sample Torkoz Giv 1B.

Reticestus acclivitatus
Kesling and Weiss, 1953 shows a very similar outline and ornamentation, but differs in a smooth broad marginal bend.
Remarks. Based on small differences in the ornamentation, the genus Kirkbyella has been subdivided into different subgenera, i.e., Kirkbyella (Kirkbyella) Coryell and Booth, 1933, Kirkbyella (Berdanella) Sohn, 1961 and Kirkbyella (Refrathella) Becker, 1967, which nevertheless have later been considered as different genera. The poor new Moroccan material cannot solve the question of subgeneric delimitation.
Genus Refrathella Becker, 1967 Type species. Refrathella struvei Becker, 1967. Diagnosis. Kirkbyellid genus with distinct, comparatively large ventral lobe, surrounded by a crest (cristal loop), in addition lateral and dorsal cristae possible, distinct adventral rim present. Important diagnostic features. Subrectangular outline, anterior cardinal angle more rounded than the posterior one, short S 2 , reticulated surface. The distinctness of the smooth carina on the ventral lobe varies; some specimens show an indistinct carina but with a distinct pointed posterior end on the shallow ventral lobe like Berdanella sp. A sensu G. Becker et al. (2004: p. 37) reported from the Moroccan sample Torkoz IIa and Giv 1B.
Remarks. The comparatively poor preservation of the ornamentation does not allow an exact determination. The figured specimen SMF Xe 22625 shows a very indistinct shallow cristal loop, which is more distinct in Refrathella.
Occurrences. Only a few specimens from the Early Devonian (latest Emsian) of the Torkoz area, SW Morocco.

Family Eridoconchidae Henningsmoen, 1953
Important diagnostic features. Eridostracina with distinct admarginal structures like thickened ridges, rows of tubercles, or small spines at the ventral border of the lamellae.
Genus Eridoconcha Ulrich and Bassler, 1923 Type species. Eridoconcha rugosa Ulrich and Bassler, 1923. Important diagnostic features. Eridoconchids with prominent umbo and up to 11 lamellae. Zagora, 1966  Remarks. The size of the valves is larger, the outline is more variable, and the number of lamellae is higher with fewer regular rows of tubercles than in the related species Eridoconcha spinosa Zagora, 1966 from the same Thuringian locality as E. papillosa. Eridoconcha cf. rugosa Ulrich and Bassler sensu K. Zagora, 1966 shows nearly equal number of lamellae, but the spines are indistinct. This species is the only one cited in G. Becker et al. (2004) from the Torkoz area and is also known from Germany (Thuringia).

Eridoconcha papillosa
Occurrences. Early Devonian (Late Emsian) of Germany (Thuringia and Mosel area SW of Koblenz) and Torkoz area in SW Morocco, but not reported by G. Becker et al. (2004) from sample Torkoz Giv 1, resp. not mentioned above the Emsian in G. Becker et al. (2004).
Remarks. The genus Punctoprimitia was taken as a primitiid genus by Stewart, and Hendrix (1945: p. 90), but, e.g., Becker and Sanchez de Posada (1977: p. 146  Remarks. The outline of the closely related late Early Devonian Punctoprimitia cf. simplex (Stewart, 1939) sensu K. Zagora, 1968 from Thuringia, Germany seems to be more suboval and the position of the shoulder nearer to the posterior border as in P. cf. simplex sensu G. Becker and Sanchez de Posada, 1977 from the latest Early Devonian of Asturias, Spain. The larger Punctoprimitia africana Becker, 1998 is characterised by a less pronounced posterior shoulder and less distinct sulcus. The much larger P. europaea Weyant, 1967 differs in the more semicircular outline, the coarse reticulation and smaller shoulder. Because a distinct reticulation is absent, we prefer open nomenclature. Only the valves SMF Xe 22645 and 22649 show a weak ornamentation, their indistinct posterior shoulder without a depression between the shoulder and the posterior border points to juveniles of Punctoprimitia ? aff. europaea.
Occurrences. Known from the Early Devonian (latest Emsian) of the Torkoz area in SW Morocco. Weyant, 1967Weyant, *1967  Remarks. G. Becker et al. (2004: p. 74) reported one lv from the late Eifelian sample Torkoz Giv 10 (Yeraifa Formation, SW Anti-Atlas, Morocco) with paraparchitid appearance and coarse reticulation, but because of the distinct adductorial sulcus (S 2 ), the placement within the paraparchitids cannot be followed herein.
Remarks. The relatively large valve with distinct and long S 2 differs from Genus 1 sp A sensu G. Becker et al. 2004 (see remarks about Punctoprimitia aff. europaea in P. sp. TKZ) in the more elongate outline and the lack of the distinct reticulation, perhaps caused by recrystallisation. It has to be verified if the single specimen of Genus 2 sp. B sensu G. Becker et al. (2004) from the Moroccan sample Torkoz Giv 10 with indistinct reticulation may belong to the same taxon.
We prefer open nomenclature because of the poor material and unknown dimorphism.
Order Podocopida Sars, 1866 Suborder Metacopina Sylvester-Bradley, 1961Superfamily Healdiacea Harlton, 1933Family Healdiidae Harlton, 1933 Remarks. The holosolenic (= contact groove connected with hinge groove) contact groove of the larger left valve is the most important feature. The outline is subtriangularto-subovate. Posterior shoulder with spines and anterior ridge are possible. K. Zagora (1968: p. 39) reported for the first time calcified inner lamella and vestibulum in the late Early Devonian Healdia kirchbergensis K. Zagora, 1968 and Healdia sigmoidalis I. Zagora, 1968, but this could not be verified in the new Moroccan material.
Because, the poor preservation of the internal structures (e.g., the typical contact groove) of the specimens is not visible and an excact determination is impossible. Different species of Healdia have been published from the late Early Devonian of Thuringia, but they differ in the outline and reticulation pattern.

Remarks.
A detailed description and delimitation of Bythocyproidea was discussed in G. Becker et al. (2004: p.42-43). This genus is known from Early and Middle Devonian strata of Europe and Middle Devonian of Morocco, but has not been reported from the Emsian of Thuringia.
Bythocyproidea ? sp. 1 Figure 10a-d Important diagnostic features. One row of subrectangular distinct pits behind the curved anterior rim and shallow elongate pits in front of the nearly vertical posterior rim and the posterior part of the lateral surface.
Remarks. Described species of Bythocyproidea Stewart and Hendrix, 1945 are related, but they differ in the smaller and more elongate pits and less distinct ribs. Bythocyproidea polaris (Gürich, 1896) known from the Early and Middle Devonian of Europe and North Africa and recorded from the Middle Devonian of theTorkoz area was not reported from sample Torkoz Giv 1 in G. Becker et al. (2004). Diagnostic important features. In contrast to Bythocyproidea ? sp. 1, the reticulation covers the surface between the anterior rim and distinct posterior shoulder and the broadly spaced reticulae are nearly round (less elongate) with distinct pore canals. The spacing of the pits in the row behind the anterior margin is not as close as in sp. 1. Important diagnostic features. Bas-relief sculpture, which is characterised by the S-formula (mostly five vertical sulci and one horizontal sulcus) since Michel (1972) and used to discriminate species. The lateral outline varies from subrectangular to subtriangular and ovoid.

Remarks. The ornamentation of
Remarks. In the following text, the terminology is used after Michel (1972) and Adamczak (1971) in Dojen (2005). The sulci are numbered (S 1 -S 5 and S v ), and used for the S-formula sensu Michel (1972) to discriminate species in the Moroccan Polyzygia specimens. The broad anterior and posterior marginal structures (ridges or flange-like) are often not preserved, and therefore, the complete outline is not exactly known. Well-preserved anterior marginal structures are visible, e.g., on the figured valves (rv SMF Xe 22677, lv SMF Xe 22681, rv SMF Xe 22684, rv SMF Xe 22691, and lv SMF Xe 22727). The exact species determination of juvenile valves of Polyzygia is difficult (five specimens SMF Xe 23954 and two specimens SMF Xe 23951, all from sample FRA-TKZ 4c2). The surface morphology of juvenile valves is often not completely developed. The S 1 and S 5 are very distinct and the Sv is indistinct or missing. The sulcation shows close relations to Thlipsurella species without the distinct lobes of Polyzygia (see SMF Xe 23055 juv. Polyzygia vel Thlipsurella ? sp.). Some juvenile valves from sample FRA-TKZ 4c2 are assigned to P. normannica -antecedens group (see Fig. 12v-w) because of the distinctly inclined S v .
Occurrences. Polyzygia species are widespread in the Earlyto-Late Devonian of Europe and North Africa. Their stratigraphical importance was summarised by Groos-Uffenorde et al. (2000: p. 106), and the drawings of these species were later used by G. Becker (2001b: p. 454) and G. Becker et al. (2003: p. 46) in the figure of the "insculpta line" with biostratigraphically important taxa.

Important diagnostic features.
Distinctly lobate species with subrectangular outline, L 1 and L 4 ventrally connected with a relatively straight ventral lobe L V , well-developed knob-like L 2 and varying L 3 . S-formula S 1 _S v _S 5 -S 4 _S 3 --S 2 .
Remarks. Polyzygia grekoffi differs in the more bow-shaped admarginal rim and S v and the narrow L 3 is not ventrally isolated. In sample FRA-TKZ 4c2, there are a lot of P. symmetrica specimens with varying outline and varying lobation similar to those figured by Michel (1972: e.g., Figure 13) from the Santa Lucia Formation (latest Early Devonian of Spain).

Polyzygia symmetrica group
Because of the differences in the shape and development of the lobation-details and additional material will be described by Dojen et al. (in prep.)-the specimens from the new Moroccan collections are provisionally grouped into different morphotypes: a. with nearly equal-sized L 2 and L 3 ventrally isolated and not connected with the L v see P. symmetrica symmetrica Gürich, 1896, b Remarks. The outline of the valves and the position and the shape of the lobes L 2 and L 3 vary (see, e.g., Adamczak 1956, and Michel 1972. Occurrences. Late Early Devonian (latest Emsian) and Middle Devonian of Europe and North Africa. Becker, 1995Figure 12e-g ?1972Polyzygia symmetrica Gürich, 1896 fig. 33d, e, pl. 12, fig. 1 The holotype was first named and figured by Becker (1994), but the diagnosis followed in G. Becker (1995).

Important diagnostic features.
A subspecies of Polyzygia symmetrica with relatively large, knob-like L 2 , isolated dorsally and ventrally. L 3 narrow and dorsally and ventrally not isolated resp. ventrally connected with the L v . S-formula: S 1 _S v _S 5 -S 4 Remarks. Polyzygia grekoffi differs in L 2 not ventrally isolated and a more bow-shaped Sv and L v .
In P. symmetrica symmetrica, the L 2 and L 3 differ less in shape and both are isolated from the L v .
Occurrences. Late Early Devonian of Northern Spain (Santa Lucia Formation) and North Africa (SW Morocco). G. Becker et al. (2003: p. 41) listed a closely related form from section Torkoz IIb (Late Early Devonian of SW Morocco), but not cited from sample Torkoz Giv 1.
Polyzygia symmetrica var. carinata var. nov. Figure 12h- Important diagnostic features. Polyzygia symmetrica with a distinct and isolated, relatively large L 2 . The L 3 is narrow with a nearly vertical rib, dorsally connected but (sometimes only weakly) isolated ventrally and showing close relations to Polyzygia symmetrica symmetrica, although the latter valves lack the rib on the L 3 .
Remarks. The L 3 of the related Polyzygia symmetrica triebeli Becker, 1995 is connected with the L v . Further variations and their exact delimitation will follow in Dojen et al. (in prep.) Occurrence. Latest Early Devonian of SW Morocco (latest Emsian of the Torkoz area). A few Eifelian specimens of section Bou Tserfine will be described in a forthcoming paper by Dojen et al. Remarks. This variable group is characterised by reticulated lobes L 1 and L 4 , a small L 2 and a narrow L 3 . Because of the ongoing discussion on the independence of P. beckmanni antecedens and P. normannica, all reticulated Polyzygia specimens from the new Moroccan samples from the Torkoz area are cited as P. normannica-antecedens group.

Polyzygia normannica-antecedens group
The oldest representative of this group is Polyzygia normannica Weyant, 1967 in the Early Devonian. The relatively small L 2 of this species is ventrally connected to the ventrstreightal lobe, the S 4 is very short, and the L 4 is large and reticulated. The youngest representative of this group is Polyzygia beckmanni beckmanni Krömmelbein, 1954 common in the late Middle Devonian (latest Givetian) and early Late Devonian (earliest Frasnian). This less elongate species is characterised by distinctly edged ridges and a long and curved L 3 . There is no great difference in the size and shape of L 2 and the reflected image of L 4 . Polyzygia beckmanni antecedens Zagora, 1968 was separated, because the round L 2 is only slightly connected ventrally, and L 3 is straight, narrow, and connected dorsally and ventrally. This taxon is reported from Early Emsian to Givetian strata of Europe. In contrast to G. Becker (1989: p. 143), Michel (1972) did not accept the separation of the subspecies of K. Zagora (1968) because of the great variation within the type material of P. beckmanni.
Polyzygia sp. ex gr. P. antecedens of Dojen (2005) is characterised by distinctly bordered rather straight and narrow lobes and sculptured L 2 . The outline and ornamentation of the Early Devonian Polyzygia sp. 1 sensu Lethiers et al. (1985) is comparable to P. normannica and P. beckmanni antecedens, but in addition, the L 1 and L 4 are surrounded by a distinct, but narrow rib. The Early Devonian (Pragian-to-Early Emsian) Polyzygia vinea Michel, 1972 with reticulated lobes can be distinguished by its differing sulcation and reduced L 3 .
Occurrences. The new material comes from the Early Devonian (latest Emsian) of the Torkoz area in SW Morocco. Weyant, 1980 Groos (1969) and 'Eifélien supérieur' from Ougarta), but P. grekoffi is not reported by Maillet et al. (2013) from the Ougarta Range in Algeria. Occurrences. Early Devonian (late Emsian) of Europe (for details, see G. Becker et al. 2004). The stratigraphical position of the specimens from Northern France (Lethiers et al. 1985: p. 63) has to be clarified. Hitherto, only one specimen has been cited by G. Becker et al. (2003;2004) from Morocco, section Torkoz IIb, but not from section Torkoz Giv.

Polyzygia insculpta ssp. indet Figure 12cc
Remarks. The figured specimen from sample FRA-TKZ 4c2, section Hassi Mouf South (SMF Xe 22737) is partly damaged, but may be related to P. insculpta insculpta Becker, 1964 with reduced ornamentation. The sulci and the L 2 and L 3 are less distinct as in P. inculpta beckeri Zagora, 1968. Occurrences. Restricted to the Early Devonian (Pragianlate Emsian) of Europe and N-Africa. G. Becker et al. (2004: p. 45) cited the species only from section Torkoz II, but not from section Torkoz Giv. Material from Poland was originally dated as Middle Devonian (Grzegorzowice Formation sensu Adamczak 1968 and, but later, the latest Emsian age was verified by conodonts (Malec and Turnau 1997), only the uppermost beds were dated as basal Eifelian.

Polyzygia kroemmelbeini
Genus Favulella Swartz and Swain, 1941 Type species. Bythocypris favulosa Jones, 1889.  Becker, 2001 from Spain is closely related, but differs in the more egg-shaped outline and the very coarse reticulation. The smooth extramarginal ridge/rim parallel to the borders is less velum-like and the outline less ropolonellid compared with those of Leptoprimitia Kummerow, 1953. Occurrences. Early Devonian (Emsian) and Middle Devonian (Eifelian) of Spain and Morocco. Hitherto only known from the early Emsian of the Torkoz area (Torkoz IIa of G. Becker et al. 2004), the new Moroccan material is of late Emsian age.

Favulella ? sp. Figure 13h
Remarks. Some specimens in sample FRA-TKZ 4c2, section Hassi Mouf South, have a distinct anterior and posterior marginal rim (SMF Xe 22724) and often indistinct reticulation, perhaps due to preservation resp. recrystallisation.

Important diagnostic features (after Dojen 2005: p. 156).
Outline suboval; hinge line depressed; ridges and spines frequently developed, particularly in the smaller RV; lateral surface reticulate or punctate; larger left valve with internally a mid-ventrally interrupted contact groove and with small bow-shaped projection.
Remarks. The family assignment of Ponderodictya is still uncertain; see, e.g., G. Becker et al. (2004: p. 52). Figure 13a Material. Only the figured lv of SMF Xe 23050 from sample GIV 1 W from section Torkoz is well preserved. The specimen SMF Xe 22750 from sample FRA-TKZ 4c2 is less well preserved and, therefore, only provisionally included.

Important diagnostic features.
Oval outline, reticulated surface, smooth adductor muscle scar, posterodorsal and posteroventral spine and indistinct ridge parallel to the anterior end. Groos, 1969 andP. punctulifera (Hall, 1860) seem to be related, but differ in a more elongate outline. Dojen (2005) figured on pl. 14 Ponderodictya sp., ex gr. P. aggeriana Groos, 1969 from the Early Devonian (Pragian) of Aragon with varying outline and sculpture comparable to the latest Early Devonian material of Ponderodictya from the Torkoz area.
Ponderodictya ? sp. Figure 13b Remarks. Only one left valve (SMF Xe 23049) from sample Torkoz GIV 1 W was found without reticulation (perhaps due to preservation?). Remarks. The relatively large smooth muscle area instead of a muscle spot resembles Ponderodictya, but the outline of Ponderodictya is more egg-shaped, the posterodorsal angle less distinct. The straight dorsal border and the posterodorsal and posteroventral short blunt spine resemble Jenningsina Coryell and Malkin, 1936, but the distinct ribbing pattern of the latter is missing. The outline and posterior spines resemble those of the Healdiidae, but these do not show a large muscle spot and are characterised by a more distinct posterior shoulder. Coryell and Malkin, 1936 Genus Quasillites Coryell and Malkin, 1936 This genus with posteroventral and /or posterodorsal spines was subdivided in G. Becker et al. (2004: p. 52) into the following subgenera:

Important diagnostic features. Lobate quasillitid with reticulated surface and posteroventral and posterodorsal spines.
Remarks. The type species is characterised by distinct posterodorsal and posteroventral spines in front of the posterior ridge.
Occurrences. Only known from type locality Assa Giv 9, early Givetian Yeraifa Formation, SW Morocco. Description. Subrectangular outline, anterior rim and posterior shoulder, distinct knob-like L 2 , posterodorsal and posteroventral short and blunt spines at the end of the posterior shoulder. The corrugate ornamentation covers the lateral surface consisting of thin ribs and thin furrows nearly parallel to the anterior end and diverging posteriorly. Complete specimens show a distinct broad, smooth velate structure parallel to the anterior margin with tubercles at the border. The anterodorsal end of the anterior rim is more or less elevated, sometimes as a blunt spine.

Quasillites (Beckjennites) gebeckeri
Remarks. The distinctness of the ornamentation and lobation varies. The smooth muscle area is not always visible. The posterior shoulder and anterior rim are more distinct in the type species Qu. (Beckjennites) chimaera Becker, 2004, and its posterior spines are isolated in front of the posterior margin.
Occurrences. Known from the late Early Devonian of the Torkoz area, Anti-Atlas in SW Morocco.

Important diagnostic features.
Carapace outline kidneyshaped to subovate; posterior shoulder without spines; surface ornamentation of horizontal or vertical ribs.
Remarks. On Kummerows type material in the collection of the former ZGI in Berlin, studied by H. G.-U. in 1971: The figure-captions of Leptoprimitia in Kummerow (1953: pl. 4) have to be changed because of a misprint in the publication. The label of the catalogue number X 406 was L. compressa n.sp., Orig., Kamieniarnia K 3 , that is the carapace of the holotype figured by Kummerow on pl. IV, Fig. 7 a-c (non 5, 6). The label of the catalogue number X 412 was L. circumvallata n.sp., Orig. Tartak, T 5 , that is the right valve of the holotype figured by Kummerow on pl. IV, Fig. 5 (non 7 a-c).

Important diagnostic features.
Outline subelliptical, extramarginal velum dorsally interrupted and not bent to the centre, valve surface delicately granulose.
Occurrence. Late Emsian (Early Devonian) Tentaculitenschiefer, Thuringia (Germany). Important diagnostic features. Subamplete to nearly preplete outline, extramarginal velum-like rim dorsally interrupted. The dorsal part of the extramarginal rim varies, that is, the bending of the posterodorsal part to the centre is indistinct (as within L. granosa), sometimes even missing (as within L. symmetrica). The surface of the valves is granulose resp. pustulose.

Material.
Only the figured rv from sample FRA-TKZ 4c2 (SMF Xe 22795) and two questionable valves from sample Torkoz GIV 1 W (SMF Xe 23043 and Xe 23523).

Important. diagnostic features
Dorsally uninterrupted extramarginal rim parallel to the elongate suboval margin.
Remarks. Leptoprimitia ornata is characterised by an uninterrupted extramarginal rim comparable to the rim of the related L. balbiniensis Weyant, 1967 from the Early Devonian of northern France, but the latter has in addition two distinct bars dorsally in front and behind mid-length.
Occurrences. Known from the late Emsian of Thuringia (Germany) and Northern Spain, only very rare in the latest Emsian of the Torkoz area (Morocco), but not mentioned from Torkoz Giv 1.
Remarks. The slightly compressed figured valve SMF Xe 22718 shows a clear bending of the posterodorsal part of the extramarginal rim to the centre, but it is not as long as within Leptoprimitia sp. ex gr. L. polonica (Přibyl, 1953) in G. Becker et al. (2004: p. 61) reported from Torkoz Giv 1. The latter taxon shows a closer relationship to Leptoprimitia balbiniensis Weyant, 1967, because the dorsal rim on pl. 8, fig. 1 seems to be uninterrupted. Because of the subtriangular outline, Adamczak (1976) separated his new species L. dubia from L. polonica with a more subrectangular outline, but this is not followed herein because of the variation of the outlines.
Occurrences. Late and Early Middle Devonian of Europe and North Africa.
Remarks. The figured specimen SMF Xe 22637 from sample FRA-TKZ 4c2 with a ropolonellid outline is a dorsally slightly damaged rv with reticulated surface (typical for Favulella) instead of the tuberculated surface of Leptoprimitia, and the extramarginal rim is slightly rounded (similar to Favulella) and less elevated (distinctly elevated in Leptoprimitia).
Remarks. The badly preserved resp. recrystallised valves with ropolonellid outline and weak marginal carina are provisionally placed in the genus Zeuschnerina.
Occurrences. The genus Zeuschnerina with several species was described from Early and Middle Devonian sections in Europe and from the Moroccan Torkoz area by G. Becker et al. (2004), but not from the latest Early Devonian sample Torkoz Giv 1.
Derivatio nominis. Named after Karl and Ingrid Zagora in remembrance of their important ostracode research in the Devonian of Thuringia, Germany.
Diagnosis. Egg-shaped outline with straight dorsal border, anterior end higher than posterior end. Coarsely pustulose surface with anterior, anterodorsal and posterodorsal spines, some specimens with additional posteroventral spine. A very small anterior marginal structure (narrow rim, not velate) developed.
Remarks. The dorsocentral shallow node characterising Loquitzella Zagora, 1968 and a broad anterior velate structure (= marginal flange sensu G. Becker et al. 2004) of Zeuschnerina could not be verified in the present material. According to K. Zagora (1968: p. 56), Loquitzella granulosa shows a close relationship to Loquitzella mesodevonica, but differs in the lack of the dorsocentral node and less elongate outline. The extramarginal smooth carina of Zeuschnerina verruca Becker, 2004 from the Givetian of Morocco is missing. The presumption of Becker and Sanchez de Posada (1977: p. 159) that L. mesodevonica and L. granulosa are only different ontogenetic stages and could be conspecific is not accepted, because of the missing ropolonellid outline, dorsocentral node, and velate anterior marginal structure in L. granulosa and the missing distinct spines in L. mesodevonica.
According to Blumenstengel (1962: p. 14), only an anterodorsal spine is developed in the left valve of the type species, but within the Morroccan material, the presence and strength of the spines may depend on the preservation.
The position within the Ropolonellidae is questionable because of the missing ropolonellid outline. The outline shows a relationship to the Scrobiculidae Posner, 1951.

Diagnosis. See genus description.
Measurements. The specimens reported by Blumenstengel (1962) from the Harz Mountains in Germany are larger in comparison to the new Moroccan specimens.
Remarks. The outline of the related Loquitzella mesodevonica Zagora, 1968 from the Tentaculitenschiefer of Thuringia is more elongate, the tubercles of the lateral surface are less distinct, and the spines are smaller. The Moroccan specimens L. mesodevonica in G. Becker et al. (2004) show a distinct ropolonellid outline and anterior marginal flange. The figured specimen of Gen. et sp. indet. 1, aff. Euglyphella abdita Petersen, 1966? in Lethiers et al. (1985 fig. 3) from Saint Fiacre in northern France seems to be related, but the anterior spine is missing and the admarginal spines are longer.
Occurrences Smooth ostracode with elongate suboval-to-subtriangular outline and maximum height at or slightly behind mid-length; small posterior spine especially on rv, but also possible on lv; calcified inner lamella present.
Remarks. Originally described and figured as having a posteroventral spine in each valve (K. Zagora 1967: p. 705), further material of this taxon, e.g., from Turkey, Cantabrian Mountains and Morocco, show mainly a posteroventral spine only in the right valves (cf. Dojen et al. 2004: p. 744).
The determination of the specimens from sample FRA-TKZ 4c2 is uncertain, because of the missing spine and the variation of the outline.

Occurrences. Late Early Devonian (Emsian)-to-Middle
Devonian of Germany, Spain, Turkey and North Africa.
The spinose and lobated genera Kirkbyellina resp. Berounella are characterised by a distinct posterodorsal rostrum. These taxa are common in Germany and northern Spain in the 'Thuringian Ecotype' or 'mixed faunas', but they are very rare in Moroccan faunas from the Eifelian Ecotype (see below: Palaeoecology, Fig. 23).
Remarks. The prominent lobation is similar to that of Berounella spinosa Blumenstengel, 1962 from the Emsian of Germany, France and Spain. The anterodorsal spine is missing, but a distinct and small round knob-like lobe and a spine below the dorsal border above the adductorial sulcus are developed. The open posterior end (rostrum) is broken.
Occurrences. One Moroccan encrusted valve was cited in G. Becker et al. (2004: p. 72) from the Middle Devonian sample Assa Giv 9, but not reported from section Torkoz.
Order, Suborder and Superfamily unknown Remarks. The systematic position was discussed in G. Becker et al. (2004: p. 74).
Genus Roundyella Bradfield, 1935 Type species. Amphissites simplicissima Knight, 1928. Occurrences. Middle Devonian-to-Permian according to G. Becker (2001a: 40), but first occurrences within the late Early Devonian of Europe and Morocco. (Zagora, 1968)  Occurrences. Late Early Devonian and Middle Devonian of Europe. Very few valves were reported by G. Becker et al. (2004) from the early Givetian (sample Assa Giv 9) of the southwestern Anti-Atlas, Morocco.

Smooth Ostracoda indet.
Smooth and mostly damaged or recrystallized ostracodes are not discussed in the present paper. They are less common compared to other late Early Devonian ostracode faunas (e.g., Adamczak 1968Adamczak , 1976Zagora 1968). Carapaces of smooth ostracodes are extremely rare (e.g., SMF Xe 22623).

Stratigraphy of the ostracodes of the Torkoz area (H. Groos-Uffenorde)
The present paper focuses on the rich ostracode faunas from the latest Early Devonian of the Crinoid Marl Member (see Figs. 2 and 19). The ostracode faunas from the underlying Early Devonian Hollardops Member to the Middle Devonian Pinacites Limestone Member will be published by Dojen et al.

The Emsian/Eifelian boundary
The type section of the Early/Middle Devonian (Emsian/Eifelian) boundary was defined in the 'Wetteldorf Richtschnitt' in the Eifel area of western Germany by the entry of the conodont Polygnathus costatus partitus Klapper, Ziegler, and Mashkova, 1978. The subspecies are taken as species by Vodrážková et al. (2011). The boundary is located in the uppermost Heisdorf Formation very close to the transition from the Heisdorf Formation to the Lauch Formation. The ostracode distribution of these formations was summarised by G. Becker and Groos-Uffenorde (1982). No ostracodes have been found directly above the boundary; therefore, the hitherto known change of the ostracode fauna occurs slightly higher.
The ostracode faunas from the Torkoz area (see Table 1) have only very few taxa in common with those of the type section because of the different facies. Only Ctenoloculina disjuncta, Polyzygia insculpta beckeri, and 'Zygobeyrichia' occur in both areas in the latest Emsian.
According to text- fig. 1 in Gooday and Becker (1979: p. 194), only the ostracode families Craspedobolbinidae and Beyrichiidae do not cross the Early/Middle Devonian boundary, but they are important elements of the late Early Devonian worldwide benthic faunas.
In Europe, there is no complete Early/Middle Devonian boundary section available rich in ostracodes and well dated by conodonts. The isolated but diverse ostracode fauna of the Tentaculitenschiefer of Thuringia was well dated by brachiopods and tentaculites (Dalejian cancellata Zone) as late Emsian (latest Early Devonian) and summarised by K. and I. Zagora (1986). This ostracode fauna has many taxa in common with the new Moroccan faunas (samples FRA-TKZ 4, FRA-TKZ 4c2, and Torkoz GIV 1; see Table 1).
Sample FRA-TKZ 4c2 yielded only one Icriodus corniger rectirostratus, which could not be exactly dated, but could be compared with the Heisdorf and Lauch formations in the Eifel area (K. Weddige, oral comm. 2012). The ostracodes of sample FRA-TKZ 4c2 have many taxa in common with late Early Devonian faunas (e.g., late Emsian Tentaculitenschiefer of Thuringia), but very few and rare taxa show Middle Devonian aspects (e.g., the occurrence of Polyzygia symmetrica has its acme in the Middle Devonian).
Sample Tor Eif/2d from the first thick limestone bed of the Crinoid Marl Member of the Hassi Mouf section delivered only a very poor ostracode fauna (see Fig. 19) and no conodonts.
G. Becker et al. (2004) reported 13 ostracode taxa from sample Torkoz Giv 1 (= Giv 1B) from the Middle Devonian Yeraifia Formation. The sample residue of Karsten Weddige (sample GIV 1 W) was recently picked and studied by H. G.-U., and more than 20 ostracode taxa could be determined. The conodonts cited in G. Becker et al. (2004: p. 8) and additional specimens were restudied by Weddige, and dated as latest Emsian patulus Conodont Zone.
Most of the ostracodes from Torkoz Giv 1 are in common with those from FRA-TKZ 4c2 (see Table 2), and they show relationships to the very rich ostracode fauna of the latest Emsian Thuringian 'Tentaculitenschiefer' (cancellata Zone), and therefore the same age is assumed.
The underlying beyrichiacean sample FRA-TKZ 4 from shales shows similarities to nearshore faunas in areas with more terrigenous influx; therefore, the correlation of the ostracode fauna FRA-TKZ 4 and FRA-TKZ 4c2 together with those from Torkoz GIV 1 are treated separately.
The Crinoid Marl Member is overlain by the Pinacites Limestone Member of early Middle Devonian (Eifelian) age (see Fig. 19). The boundary is currently not exactly known.

Correlation of the beyrichiacean fauna of sample FRA-TKZ 4
Layers full of beyrichiacean ostracodes are widespread in Early Devonian nearshore facies of Europe (summarised in Groos-Uffenorde 1983), especially in terrigenous sediments of Germany (Rhenish Schiefergebirge, Harz Mountains, Thuringia), in shales from southern and eastern Spain, northern France, and Turkey (summarised by Nazik and Groos-Uffenorde 2016), and in limestones of northern Spain and Podolia. The most common species in the latest Early Devonian is Zygobeyrichia subcylindrica (Rh. Richter, 1863) ultimately discussed in G. Becker and Franke (2012) and characterising neritic shallow-water areas.  Table 1 The occurrences of selected Moroccan ostracodes in the Early Devonian (Emsian) of the Torkoz area compared with German occurrences in Thuringia and in the boundary stratotype in the Eifel area KF = Khebchia Formation sensu G. Becker et al. (2004), sections Torkoz IIa and IIb (Late Emsian, Morocco) TTh = 'Tentaculitenschiefer' of Thuringia sensu K. Zagora (1968) (cancellata Tentaculite Zone), Germany TKZ = Crinoid Marl Member, sample FRA-TKZ 4c2 (with one conodont Icriodus rectirostratus Bultynck, 1970) and sample FRA-TKZ 4 G 1 W = section Torkoz, unpublished conodont sample GIV 1 of Weddige (patulus Conodont Zone) G 1B = sample Torkoz Giv 1 sensu G. Becker et al. (2004) interpreted as lowermost costatus Conodont Zone Eif 2d = section Hassi Mouf-South, sample Tor Eif/2d of R.T.B., details of the ostracodes will be published by Dojen et al. Hei = latest Emsian Heisdorf Fm. in G. Becker and Groos-Uffenorde (1982) Polyzygia insculpta beckeri Zagora, 1968  Poorly preserved beyrichiacean faunas have been published from Morocco by Termier and Termier (1950). The ostracode faunas described by LeFèvre (1963LeFèvre ( , 1964 include very rare Early Devonian beyrichiacean ostracodes from Algerian Sahara sections. Groos-Uffenorde (1991: p. 341) published Cornikloedenina ? meridiana from an Early Devonian sample of G.K.B. Alberti (Hamburg) from Central Morocco. A new Beyrichiacea species Gibba kandarensis was described by Vannier (1994) from the Emsian of NW-Morocco. Baird et al. (2009) reported large, distinctive ostracodes from calcareous shales and siltstones above sandstones of the Rich 4 Member (Hassi Mouf South section, 11 km S of Torkoz, named Torkoz 5 section in Fig. 3) and below the Pinacites Limestone. Sample FRA-TKZ 4 (with rare specimens of Bollia between many large valves of Zygobeyrichia) was collected in the same section a few decimeters below sample FRA-TKZ 4c2, the latter does not contain any beyrichiacean ostracodes. The Thuringian late Emsian silicified ostracode fauna of K. Zagora (1968) contains silicified valves as well as internal moulds of mostly juvenile Z. subcylindrica besides many silicified non-beyrichiacean taxa. Comparable to the Moroccan section, this rich and diversified ostracode fauna of horizon III of the Thuringian 'Tentaculitenschiefer' is underlain by shales dominated by Z. subcylindrica.
A late Early Devonian age of sample FRA-TKZ 4 is assumed, because no layers full of large beyrichiacean ostracodes from well-dated Middle Devonian sections have been described. However, the lack of large beyrichiacean ostracodes in early Middle Devonian strata may also be due to a widespread facies change because of a deepening of the sea after the Early Devonian. The planned paper by Dojen et al. will focus on the relationship between event stratigraphy and Devonian ostracodes.

Correlation of non-beyrichiacean ostracode faunas of Europe and Morocco
The international Early/Middle Devonian boundary was placed between the late Emsian Heisdorf Formation and the basal Eifelian Lauch Formation in the German Eifel stratotype area and defined by conodonts (boundary between Polygnathus costatus patulus and P. c. partitus Zones). Small ostracode faunas were described by G. Becker and Groos-Uffenorde (1982). Only some of the Moroccan ostracode species are in common (see Table 1: Hei, Lau). No  ---Quasillites (Beckjennites) gebeckeri n.sp. ostracodes were found directly above the boundary in the stratotype section; therefore, the change of the ostracode fauna is slightly higher. The ostracode faunas from the SW Dra Valley in Morocco have only very few taxa in common because of the different facies. The shallow-water taxa, very abundant and diverse in central Europe (e.g., Kozlowskiella and Poloniella) are completely missing in the Torkoz area. From the Rhenish Schiefergebirge and Harz Mountains, only very few non-beyrichiacean ostracodes near the Emsian/Eifelian boundary are known, e.g., Grigo (1994a, b), Groos (1969), and Stoltidis (1971) besides the beyrichiacean ostracode faunas. Conodont data are very rare because of the mostly terrigenous nearshore facies. Only very few ostracodes are in common with the Moroccan faunas and typical components of the German sections are completely missing in Morocco.
The very well-preserved calcareous ostracode faunas of Poland described by Adamczak (1968Adamczak ( , 1976 have been dated as Middle Devonian. The fossiliferous Grzegorzowice beds were interpreted as basal Middle Devonian overlying the Early Devonian terrigenous sediments, but according to the conodont faunas studied by Malec and Turnau (1997), the Grzegorzowice beds were dated as late Emsian; only the uppermost beds range into the partitus Conodont Zone (with Polygnathus costatus partitus) of the basal Eifelian. Many species described by Adamczak (1968Adamczak ( , 1971Adamczak ( , 1976 from Poland are very similar or even conspecific to those described by K. Zagora (1968) from Thuringia. The Moroccan samples FRA-TKZ 4c2 and GIV 1 have some sculptured taxa, e.g., Polyzygia, Ctenoloculina, Jenningsina, Quasillites, and Leptoprimitia in common, but relatively smooth taxa, such as Ochescapha and the diverse Primitiopsacea and Bairdiacea are missing in the latest Early Devonian of the Torkoz area.
Many late Early Devonian and Middle Devonian calcareous ostracode faunas have been described from Bohemian limestones, e.g., by Přibyl (1953Přibyl ( , 1955Přibyl ( , 1987. Only very few genera are in common with the Moroccan latest Early Devonian faunas. The silicified diverse ostracode fauna from Late Early Devonian to earliest Middle Devonian limestones from the Western Pontides, NW Turkey described by Olempska et al 2015 have many taxa in common with Thuringia (Germany), Cantabrian Mountains (Spain), and Morocco.
The detailed study of the Devonian of the 'Rade de Brest' in Brittany (Northern France) by Morzadec (1983: p. 278) shows some similarities of facies, but only three ostracode taxa (including Polyzygia insculpta beckeri) have been reported from the St. Fiacre Formation at the base of the Middle Devonian. Silicified ostracodes from the so-called 'Eifélien' of Saint Fiacre (Finistère) figured by Lethiers et al. (1985), have not been published in detail, but they show many taxa in common with the sample FRA-TKZ 4c2 and may also be dated as latest Early Devonian.
The rich and diversified Early Devonian ostracode faunas published by Feist and Groos-Uffenorde (1979) from the Montagne Noire in southern France do not show close relations to the Moroccan sample FRA-TKZ 4c2 because of the younger age of the latter.
Many Devonian ostracodes have been described, e.g., by G. Becker and Sanchez de Posada (1977) and G. Becker (1989Becker ( , 1998Becker ( , 2001a from the Cantabrian Mountains in Northern Spain. The late Emsian faunas have species in common with those of sample FRA-TKZ 4c2. Of special interest is the last occurrence of Polyzygia insculpta beckeri, cited, e.g., by G. Becker et al. (2004: p. 49) in the latest Early Devonian/latest Emsian of Northern Spain. We do not accept the determination of the figured P. insculpta ssp. indet. in G. Becker (1989: p. 42, Gustalapiedra Formation, late Eifelian, figured on pl. 5, fig. 3); therefore, hitherto no Middle Devonian occurrences are known.
Many Early Devonian ostracodes have been described from the Iberian Chains in Eastern Spain by Dojen (2005), but the Dalejian resp. Emsian/Eifelian boundary interval is not represented.
The Algerian Early Devonian ostracode faunas described by LeFèvre (1963LeFèvre ( , 1971 from Saharan sections show some similarities at the generic level with sample FRA-TKZ 4c2. Polyzygia kroemmelbeini is reported only from Emsian strata and P. symmetrica from the late Couvinian (in Maillet et al., 2013 cited above the partitus Zone). Maillet et al. (2013) listed some species from the boundary interval.
Many Early Devonian ostracodes have been described from North American limestones and marls, e.g., by Berdan and Copeland (1973), Lundin (1968) and Swartz (1936), but only very few taxa are in common with the Moroccan fauna. According to Berdan (1990: p. 229), 'It seems most likely that barriers separating the provinces were either land or deep water'.
From South America, only latest Silurian-to-earliest Early Devonian (Lochkovian) ostracodes were described by Vannier et al. (1995), including beyrichiacean-dominated faunas. The slightly older ostracodes are different and do not show any relations to the Early Devonian Moroccan ostracode faunas.
The silicified ostracode faunas of the Emsian Receptaculites Limestone of New South Wales in Australia (Reynolds 1978) are dominated by smooth taxa indicating offshore environment. The Australian genera Acanthoscapha, Ampuloides, Tricornina, and new spinose taxa show relations to the Thuringian fauna described by I.  from the Tentaculiten-Knollenkalk, but there is no relation to the slightly younger Moroccan ostracode fauna.
The Early Devonian ostracode fauna from Central Japan described by Kuwano (1987) delivered many spinose taxa and, therefore, belongs to the Thuringian Ecotype with less relations to the new Moroccan ostracode faunas. Only very few Early Devonian Moroccan ostracodes show relationships to Chinese or Russian faunas, mostly because of facies differences.

Introduction
Palynological sample PMP 774 is originally derived from the non-magnetic fraction of the conodont preparation of sample GIV 1 W (= GIV 1A sampled by K. Weddige) from the Torkoz section (G. Becker et al. 2004). The residue was palynologically treated with hydrochloric acid (38%) and hydrofluoric acid (43%) to remove carbonates and silicates, to enrich the organic content (e.g., Traverse 2007). The remaining kerogen was sieved (10 µm mesh width) without any oxidation. Palynological slides were studied using a transmitted-light microscope (Nikon Eclipse 90i).
Palynological samples from the field studies in 2007 in the section Hassi Mouf South have been proven non-productive; the analysed rocks (24 samples in total) are uniformly depleted in organic matter most probably due to weathering processes.
The citation of stratigraphical occurrences in the following text are taken from the cited references. Because they have not been changed according to recent definitions of the stratigraphical nomenclature, they are shown in brackets.

Results
The sample analysed is generally poor in organic matter and the frequency of palynomorphs is low. Palynomorphs are without exception marine components (acritarchs, prasinophytes, and a single scolecodont specimen), no miospores or other terrestrially derived material like phytoclasts are present. However, it cannot be excluded that separation techniques of the conodont processing-e.g., magnetic and density fractionation-may have influenced the composition of the palynological assemblage. The assemblage is of low diversity and specimens are moderate-to-poorly preserved. Accordingly, palynofacies interpretation as well as taxonomic studies are limited. Nevertheless, due to the lack of organic markers of terrestrial origin, it can be concluded that the depositional environment was an open-marine shelf at some distance from the coast.
The sample yielded very few prasinophytes such as small leiospheres and specimens of the genus Cymatiosphaera. Acritarchs are represented by rare taxa assigned to the genera Cymbosphaeridium, Multiplicisphaeridium, and Veryhachium (Fig. 20).
Cymatiosphaera carminae (Cramer, 1964) (Fig. 20a) was first described and subsequently reported from the upper part of the La Vid Formation (NW Province of Léon, Spain); the species is rare but characteristic for the Emsian in Spain, e.g., Cramer (1964), Cramer and Diéz (1976) and Cramer (1967) probably misspelt as C. carmencitae). Cymatiosphaera carminae has also been recorded from northern Africa (Algeria) in a systematic discussion with the genus Crameria ) and the Anti-Atlas, Marocco (Snape 1993). Hence, it can be concluded that this species is restricted to northern Gondwana and peri-Gondwana, respectively.
The genus Multiplicisphaeridium is represented by quite a number of species and is very common in Palaeozoic sequences. The specimen reported herein belongs to Multiplicisphaeridium raspum (Cramer) Eisenack et al., 1973 (Fig. 20g). A further specimen with comparatively longer processes is provisionally assigned to Multiplicisphaeridium cf. raspum (Fig. 20f). The species M. raspum was also established from the La Vid Formation in Spain with a given specific range for the "Siegenian" to Emsian (Cramer 1964(Cramer , 1967Eisenack et al. 1973, Cramer andDiéz 1976). The species-or morphotypes similar to this species-were also frequently reported from the Ordovician to the Devonian worldwide, but the overall data suggest a slight predominance for the Silurian-to-Early Devonian of Gondwana and peri-Gondwana (see Palynodata Inc. and White, 2008).
The genus Veryhachium is one of the most frequently reported acritarchs at all and very common in the Palaeozoic with a cosmopolitan distribution. The illustrated triangular form with scabrate-to-rugulate sculpture elements (Fig. 20b) is assigned to Veryhachium scabratum established by Cramer (1964) from the San Pedro Formation in NW-Spain. The stratigraphic range of this taxon is "Ludlovian to Lower Gedinnian" (Cramer 1964;Jardiné et al. 1974). Morphologically similar triangular forms-also treated as Arkonia scabrata or Striatotheca scabratum-were subsequently noted from the Ordovician and Silurian. For taxonomic discussions, see Servais (1997), Fensome et al. (1991), and Le Hérissé (2002).
The tetragonal specimen (Fig. 20c) is attributed to the genus Veryhachium with a question mark because of the poor preservation; the four processes are incomplete; their length and termination are unknown. The specimen could be provisionally attributed to ?Veryhachium cf. V. inflatissimum. This species was described by Cramer (1964) from the La Vid Shale with a stratigraphic range from "Middle Siegenian to Emsian" (e.g., Diez and Cramer 1974). Older occurrences are from Ludlow to Přidoli in Argentina (e.g., Rubinstein 1995), younger are from the "Givetian" of Libya (Moreau-Benoit 1984) and Algeria (Abdesselam-Rouighi 1986).
In conclusion, very few palynological data exist from the Devonian of Morocco (e.g., cutting material from the Doukkala and Essaouira basins reported by Rahmani-Antari 1990 and Rahmani-Antari and Lachkar 2001, respectively, and the Anti-Atlas by Snape 1993), but none from the Torkoz area so far. The palynostratigraphic zonation provided by Rahmani-Antari and Lachkar (2001) is mainly based on miospores. The herein reported prasinophyte and acritarch taxa from the Torkoz section (sample GIV 1 W) can best be compared with those described and established from the Lower Devonian of NW-Spain (e.g., Cramer 1964). They suggest a late Emsian age mainly based on the occurrence of Cymatiosphaera carminae, which is predominant in the Emsian. However, due to the scarce occurrence of palynomorphs at all and in particular the lack of miospores and chitinozoans, more data from other fossil groups are needed to solve the biostatigraphic puzzle.

Discussion
The brachiopod material is scarce, but allows some stratigraphic, palaeobiogeographic, and biofacial remarks: 1. A well-preserved dorsal valve (SMF 102111; Fig. 21a) and an articulated shell (SMF 102115; Fig. 21b) of a leptaenid strophomenide are questionably determined as Leptaena dicax nom. nud. García-Alcalde (sensu Racheboeuf, 1981). Rugation of the exterior and the elevated dorsal muscle platform are consistent with this assignment. As the internal characters of the ventral valve are unknown, a conclusive determination is not possible. The taxon L. dicax nom. nud. was reported from the upper (and uppermost) Emsian of the Armorican Massif (NW France) and the Spanish Cantabrian Mountains (Racheboeuf 1981), and from the Ougarta Chains in Algeria (Racheboeuf 1997 Walmsley and Boucot 1975: p. 62), but it has also been described from the Mandeln Formation (latest Emsian) in the Rhenish Schiefergebirge (Dahmer 1915) and from the Marettes and Reun ar C'Hrank formations (late Emsian) in the Armorican Massif (Melou 1981a, b); moreover, it has been recorded from the 'Couvinien' (latest Emsian-Eifelian) of the Ardennes (Maillieux 1938 In summary, the brachiopods suggest a latest Emsian-earliest Eifelian age, with Alatiformia cf. alatiformis pointing to this interval and Rhipidomella cf. subcordiformis rather indicating an earliest Eifelian age, whereas Leptaena dicax ? nom. nud. and possibly also Tyersella cf. tetragona and Schizophoria sp. are more suggestive of a late Emsian age. Weighing up all the arguments, the stratigraphic position of this horizon is possibly very close to the Emsian-Eifelian boundary and more probably slightly older than the boundary-i.e., of Heisdorf age (latest Emsian). A few finds from the underlying Rich 4 Sandstone of the Khebchia Formation in the Torkoz IIa section (Jansen et al. 2007: p. 30), in particular Iridistrophia (Flabellistrophia) cf. hipponyx (Schnur, 1851) and Sollispirifer cf. steiningeri (Solle, 1953), suggest a latest Emsian age also for this slightly lower level. In general, the specimens from section Hassi Mouf South show relationships to approximately coeval ones from the Eifel region, the Holy Cross Mountains, the Armorican Massif, and the Cantabrian Mountains. Litho-and biofacial traits, in particular the brachiopod taxa rather preferring clear water, are consistent with the allorhenotypic subfacies (Jansen 2016). Accordingly, the palaeoenvironment of the Hassi Mouf fauna was the open-marine shelf with relatively little and fine-grained siliciclastic input of terrestrial origin.

Palaeogeographic distribution of Early Devonian ostracodes in the Torkoz area (H. Groos-Uffenorde)
According to Scotese (2020), the Iapetus Ocean had closed by Mid-Palaeozoic times. This continental collision of Laurentia and Baltica resulted in the formation of the Caledonides in Scandinavia, northern Great Britain and Greenland, and the Northern Appalachian Mountain Range along eastern North America. The Rheic Ocean separated Gondwana from Laurussia and began to close in the Devonian, but the exact time within the Devonian differs in the literature and is still in Discussion.
The late Early Devonian (Emsian) Baltic-British ostracode province (Fig. 22b) sensu Berdan (1990: p. 228) is not known from the Emsian of North America, Great Britain, or the Baltic area (without the Pontides) because of differing facies. The North American Acadian Mountains may have served as a land barrier between the Baltic-British and Appohimchi Province, but in Emsian time, the provinces are less different and the Thuringian Ecotype ostracodes are also known from the Appohimchi Province. According to Berdan (1990: p. 229), it seems most likely that the barriers separating the provinces were either land or deep water. The Moroccan Emsian ostracode faunas belong to the Baltic-British province sensu Berdan (1990: p. 228) reported, e.g., from the Emsian of Germany, France, Spain, and North-Africa and no longer present in North America, but the ostracode genera Bollia, Ulrichia, Ctenoloculina, and Favulella are in common.
The palaeogeographical reconstruction of Paris and Robardet (1990: fig. 4) (Fig. 22c) shows a wide area of continental shelves and slopes in the northeast of Gondwana south of the Rheic Ocean. Many localities with large beyrichiacean ostracodes can be found in this area, but the position of important localities like those, e.g., in Podolia and Germany are separated from Perigondwana by the Rheic Ocean. Dojen (2009: p. 220) showed possible migration paths of beyrichiacean ostracodes also using the reconstruction of Cocks and Torsvik (2006), but she concluded that shallow-water connections existed between Laurussia, Gondwana, and Perigondwana, and questioned the presence of the Rheic Ocean in late Silurian-to-Early Devonian times. Olempska et al. (2014) described new silicified Early Devonian non-beyrichiacean ostracodes from the western Pontides/Istanbul Terrane, discussed the different reconstructions of the palaeogeographic positions, and concluded a Perigondwanan (Avalonian) setting of the Pontides during Devonian time. Maillet et al. (2016) studied Givetian ostracodes from NW-Spain and proposed close relations between the Cantabrian Zone (NW-Spain), the Armorican Massif (W-France), the Mouthoumet Massif (S-France), and North Africa (Morocco and Algeria) suggesting a narrow oceanic space between the western European terranes and the northern Gondwanan margin that involves an advanced phase of closure of the 'Medio-European Ocean'.
The wide distribution and frequent occurrences of the ostracode genera Zygobeyrichia and Carinokloedenia were interpreted by G. Becker and Franke (2012: p. 5) as (nekto) benthic inhabitants of mostly offshore settings of the Rheic coasts (Laurussia, Perigondwana and North Gondwana). The dispersal of these large benthic beyrichiacean ostracodes, which lack a free-swimming planktonic larval stage, is only possible in marine shallow-water areas and not across a deep ocean. The question of the depth and width of the Rheic is still in discussion, and the same is for the Iapetus Ocean in Ordovician time (Schallreuter and Siveter 1985: p. 592). We do not follow the Early Devonian (400 Ma) palaeogeographic reconstruction of Cocks and Torsvik (2006: p. 90, fig. 9). This figure was used in Olempska et al. (2014: p. 14) and Nazik and Groos-Uffenorde (2016: p. 21), but is questioned because of the missing shallow-water areas for dispersal of benthic ostracodes to both sides of this ocean. The palaeogeographic interpretation of Crasquin and Horne (2018: p. 5) based on the palaeogeographic reconstruction of Blakey (2016) with a broad Rheic Ocean between Euramerica and Gondwana does not show any possibility for dispersal of benthic shallow-water ostracodes across this deep ocean. In contrast, Tanaka et al. (2019: fig. 7) used the palaeogeographic map of Torsvik and Cox (2017) and placed all known Early Devonian localities of the ostracode Kirkbyellina spinosa (Blumenstenel, 1962) inclusive those of the Rhenish Schiefergebirge and Thuringia in the south of a broad Rheic Ocean.
In contrast to our interpretation, Crasquin and Horne (2018: fig. 3, 7) preferred the reconstruction of Blakey (2016) with an open Rheic Ocean and deep water (Thuringian Ecotype) ostracod faunas on both sides of this ocean interpreted as palaeopsychrosphaeric fauna inhabiting bathyal to abyssal, cold, well-oxygenated waters.

Palaeoecology of the ostracode faunas from the Torkoz area (H. Groos-Uffenorde and C. Dojen)
The Devonian ostracode palaeoecology was summarised in Groos-Uffenorde et al. (2000: fig. 1) including the different interpretations focussing on sedimentology and facies. Publications on Early Devonian ostracodes were listed according to their regional distribution by Nazik and Groos-Uffenorde (2016: p. 22), but not including studies from North America, Bolivia, Uzbekistan, Salair, China, and Japan.
The widespread 'mixed faunas' sensu G. Becker (e.g., 2000: p. 558, text- fig. 3) (Mischfaunen resp. Mixed Assemblages sensu G. Becker and Bless 1990) seem to be included by Casier (2008) and Crasquin and Horne (2018) without  Cocks and Torsvik (2006: p. 90); b late Early Devonian (Emsian) ostracode provinces after Berdan (1990: fig. 5). The position of the new Moroccan faunas is marked with a red star; c occurrences of large benthic beyrichiacean ostracodes plotted on the map of Paris and Robardet (1990: p. 204) after Nazik and Groos-Uffenorde (2016: p. 221). The suggested position of the Turkish Pontides is moved by Nazik et al (2018) to Laurussia resp. Baltica (as done in Fig. e); d the Middle Devonian palaeoglobe shows the closure of the Rheic Ocean during the first stages in the formation of Pangea after Scotese (from www. scotese.com{moremaps2.htm on Sept. 07th 2017); e black stars indicating areas with Early Devonian ostracode localities are plotted on the base map taken on May 13th 2020 from www.scotese. com{moremaps2.htm, the position of the new Moroccan faunas is marked in red ◂ discussion within the Thuringian Ecotype sensu G. Becker resp. the Mega-Assemblage IV sensu Casier (2008).
The first ostracodes above the Rich 4 Sandstone Member (topmost Khebchia Formation, late Emsian) in the Hassi Mouf South section (sample FRA-TKZ 4) have been found in marly shales, represented by a nearly monospecific layer with large beyrichiacean ostracodes (many Zygobeyrichia specimens and very rare small non-beyrichiaceans). They may indicate a relatively restricted nearshore area with terrigenous influx (beyrichiid complex sensu Polenova 1971). The nektobenthic mode of life suggested for Zygobeyrichia by G. Becker and Franke (2012: p. 95) seems unlikely because of the anteroventral crumina in heteromorphs.
The new silicified ostracode faunas from the Crinoid Marl Member of the Torkoz area (samples FRA-TKZ 4c2, Torkoz GIV 1, and Tor Eif/2d) are interpreted as autochthonous 'Eifelian Ecotype' sensu G. Becker resp. 'Eifel Mega-Assemblage, MA III' (Mega-Assemblage de l'Eifel sensu Casier 2017). They contain diverse sculptured taxa (lobated, ribbed, and reticulated) of different size (juvenile and adult valves, rare carapaces), and extremely rare specimens of spinose taxa (e.g., Kirkbyellina resp. Berounella) characterising open-marine environments below wave base. The related, well-preserved silicified ostracode fauna described by K. Zagora (1968) from the Thuringian 'Tentaculitenschiefer' (latest Emsian cancellata Dacryoconarid Zone) was interpreted by K. and I. Zagora (1986) as shallow-water fauna of the Eifelian Ecotype transported by proximal turbidity currents into a deeper area before being embedded. This interpretation was not accepted by G. Becker et al. (2004: p. 82) and is now included in his 'mixed faunas'. The preservation of the figured ostracodes in K. Zagora (1968) does not show any sign of transport or damage. For many years, H. G.-U. tried to get access to this very important fauna, but the material of K. Zagora (1968) including the types is still not available in the collection of the Geological Institute of the University of Jena, Germany. Only the ostracodes described by I.  have been found in the Geological magazine of the University of Jena.
In common with the new Moroccan, faunas are the heavily sculptured genera such as Bollia, Ctenoloulina, Eridoconcha, Jenningsina, Karlingrella, Kirkbyrhiza, Polyzygia, Punctoprimitia, Ulrichia, and Zygobeyrichia. However, in contrast to the new ostracode faunas in the latest Early Devonian of the Torkoz area, the Thuringian fauna of K. Zagora (1968) contains spinose genera such as Baschkirina, Bufina, Healdia, Praepilatina, and Tricornina. In G. Becker et al. (2004: p. 83), the ostracode assemblage from Zagora's 'type cancellata zone' is therefore interpreted as clearly mixed faunas indicating an offshore position below wave base. They are comparable to the mixed faunas in G. Becker et al. (2004) from the Emsian (Oui-n-Mesdour and Khebchia formations), and in Dojen et al. (2010) from the late Emsian to early Eifelian from SW Morocco.
A detailed description of new Moroccan ostracodes of the 'mixed fauna' will follow in Dojen et al. Late Early Devonian ostracode faunas of the Thuringian Ecotype (= Mega-Assemblage MA IV) with many spinose podocopids and the Entomozoacean/Myodocopida Ecotype (= Mega-Assemblage MA V) from deeper water sediments have not yet been recorded from the Torkoz area, but they are known from younger sediments in Morocco.
Surprisingly, very nearshore sculptured genera like Kozlowskiella and Poloniella ("subtype a" of the Eifelian Ecotype sensu G. Becker 2000b), amphissitids, bufinids, and smooth ostracodes (like bairdiids, bairdiocypridids, pachydomellids) are completely missing in the new Moroccan ostracode faunas of the Crinoid Marl Member in the Torkoz area, but they are common in time-equivalent faunas of, e.g., Germany, Bohemia, and Poland. This may indicate less agitated and slightly deeper water for the Moroccan ostracodes in the latest Emsian.

Conclusion
A very rich and diversified ostracode fauna (22 genera resp. 32 species) from one conodont sample residue of the latest Early Devonian Yeraifia Formation of section Hassi Mouf South is described and 49 ostracode taxa from the Torkoz area in SW Morocco are discussed. The new silicified fauna of the 'Eifelian Ecotype' shows very close relationships to the silicified Thuringian ostracode fauna of the same age. It has to be verified why there are minor relations to the well-preserved, but calcareous ostracode fauna of the latest Early Devonian Grzegorzowice Beds in the Holy Cross Mountains of Poland (e.g., Adamczak 1968Adamczak , 1971Adamczak , 1976, likewise interpreted as Eifelian Ecotype but with lots of bairdiids, bairdiocypridinids, pachydomellids, and bufinids. In common are only the taxa Ctenoloculina, Jenningsina, Leptoprimitia, Polyzygia kroemmelbeini, P. symmetrica, and P. insculpta. Associated brachiopods from the first limestone of the Crinoid Marl Member (Lower Yeraifa Formation) suggest an age close to the Emsian/Eifelian boundary for sample Fig. 23 Summaries of Devonian ostracode palaeoecology. a Distribution of ostracode ecotypes in the review of G. Becker (2000a, b: textfig . 3); shallow-water faunas near the reef to deep-water faunas; b early Devonian 'Eifelian Ecotype' ostracodes from Aragon (Spain) in Dojen (2005: fig. 9.4) concentrating on shallow-water faunas; c Devonian ostracode assemblages sensu Casier (2008) after Maillet et al. (2016: fig. 1F modified) with very shallow/lagoonal to basinal faunas; d important late Early Devonian ostracode faunas of the Torkoz area, SW Morocco. The ecological assignment of the 'mixed faunas ' modified after Dojen et al (2010: fig. 3) with supplements of some typical taxa from the 'Eifelian Ecotype' faunas of the lower Crinoid Marl Member ◂ Tor Eif/2b (Hassi Mouf South section) and more likely a latest Emsian age. This brachiopod fauna is consistent with an open-marine shelf environment with relatively little terrestrial input, corresponding to the sedimentological interpretation. It shows relationships to coeval brachiopod faunas from the Cantabrian Mountains, the Armorican Massif, the Eifel region, and the Holy Cross Mountains.
The composition of the palynological assemblage is somewhat deficient, but the reported marine acritarchs, prasinophytes, and the scolecodont from the Torkoz section (sample GIV 1 W) suggest an open shelf environment. Palaeogeographically, the identified taxa show a prevailing Gondwanan affinity and can be best compared with those recorded from northern Spain. The studied prasinophyte and acritarch taxa support as well the stratigraphic assignment of the ostracode and brachiopod faunas as late Emsian age close to the Early/Middle Devonian boundary.
In summary, the described arguments favour a late Emsian (latest Early Devonian) age for all studied samples (FRA-TKZ 4, FRA-TKZ 4c2 and Tor Eif/2b from section Hassi Mouf South, Torkoz Giv 1B and GIV 1 W from section Torkoz). This implies the position of the Emsian/Eifelian boundary within the Crinoid Marl Member and not at the top or within the underlying Rich 4 Sandstone Member as published from the southwestern Dra Valley area in SW Morocco by e.g., R.T. Becker et al. (2004aBecker et al. ( , 2004c and Dojen et al. (2010).