New species and nomenclatural changes in Cynorkis (Orchidaceae) from Madagascar, the Comoros and the Mascarenes

Four new species, Cynorkis kiehnii, C. marianneae, C. marmorata and C. murex, are described for the first time. Cynorkis frappieri and C. raymondiana are compared, with the latter reduced to a synonym of the former. Cynorkis gaesiformis, C. galeata, C. nutans and C. stenoglossa are compared and considered one variable species, with the name C. nutans having priority. Additional information is provided about C. mammuthus following the discovery of living material in N Madagascar.


Materials & Methods
As part of ongoing research and fieldwork on the orchid flora of Madagascar at the Royal Botanic Gardens Kew, the University of Vienna and PBZT Antananarivo, specimens of putative new taxa were compared with descriptions, herbarium material and drawings of all the type specimens of the genus to ascertain their novelty. This has resulted in the recognition of a number of new species and a better understanding of the nomenclature of others.
The conservation status of the new species given in this paper are summaries of the full IUCN Red List assessments which will be completed and submitted for review and publication by IUCN once the species names are validly published and therefore available for assessment. All the assessments have been compiled based on current knowledge of these taxa, by one of the authors (Landy Rajaovelona), who is an IUCN Red List assessor, using the IUCN Red List Categories and Criteria (2012). RECOGNITION. With its entire mid-lobe of the rostellum and two long arms, each with a rounded side-lobe Cynorkis kiehnii belongs in section Gibbosorchis H.Perrier ex Hermans (Hermans et al. 2007: 290). It is recognised by its long lanceolate leaves, a large leaf sheath, a tall 1 -3-flowered inflorescence, and glabrous flowers with a densely hirsute ovary, an entire strongly incurved lip, a spur subulate in the middle and the apical half thickened and flattened, and long divided rostellum arms. It is undoubtedly very close to but also very different from two Cynorkis described recently from the same area: C. mammuthus Hermans & P.J. Cribb (Hermans et al. 2017: 13) and C. elephantina Hermans, Andriant. & Sieder (Hermans et al. 2017: 7) (compared in Table 1). They share the entire lip, hirsute ovary and column shape but C. kiehnii differs from the former by the fewer flowers almost a third the size, the broader petals, the narrowly lanceolate lip (vs broadly oblanceolate) and the differently shaped spur which is subulate in the middle and the apical half thickened and flattened (vs subulate) along its length. It differs from C. elephantina in particular by its fewer elongate lanceolate leaves (vs obliquely lanceolate), 1 -3 flowers (vs 15 -22), the flowers that are about 1 3 smaller with a spur that is about half the length and subulate in the middle with the apical half thickened and flattened (vs subulate along its entire length), and its purple-pink tinted whitish flowers (vs ivory-white spotted with burgundy). DISTRIBUTION. Known only from the Bealanana area in northern Madagascar. SPECIMENS EXAMINED. MADAGASCAR. Mahajanga prov., Bealanana area, 1227m, Jan. 2018, Gamisch, Sieder, Prehsler & Andriantiana 7586 (holotype WU!). HABITAT. On top of inselberg, on basalt rock in a thin layer of moss, also in cracks in the rock, growing with Nematostylis anthophylla (A. Rich. ex DC.) Baill. (Baillon 1879: 198) (Rubiaceae) and Cynorkis siederi Hermans & Andriant. (Hermans et al. 2017: 18). 1200 -1250 m. CONSERVATION STATUS. Cynorkis kiehnii is only known from a single unprotected locality on top of inselbergs in Sofia region, Mahajanga province. It was found alongside a road and such fragments are known to be particularly at risk from human development. The species is assessed as Critically Endangered CR based on Criterion D, with the number of mature individuals likely to be fewer than 50 (around 20 plants were found on a single inselberg), and under criterion B2ab(i,ii,iii) with a continuing decline in the value of the AOO and the EOO estimated to be less than 10 km 2 and the habitat quality due to human activities such as land clearing and fire for agricultural uses. FLOWERING TIME. January -February. ETYMOLOGY Flowers 2.5 × 1.5 cm, with pale olive green petals and sepals, a white lip with a crimson purple base, becoming darker within the throat and a brownish red spur, a white column with the margins purple, and a green ovary with purple-red grooves. Pedicel with ovary fusiform, slightly arched, glabrous except for the join with the base of the column which has a few scattered glandular hairs, 21 -23 × 1 2.1 mm. Dorsal sepal ovate, 8.2 -8.5 × 3.5 -3.6 mm, forming a hood over the column with the petals obtuse, with glandular hairs on the exterior. Lateral sepals spreading, oval-lanceolate, 9.9 -10.2 × 4.6 -5.1 mm, obtuse, with a few hairs at the base. Petals narrowly lanceolate, falcate, 8.2 -8.4 × 1.9 -2 mm. Lip unequally 4-lobed, 21 -23 × 11 -13 mm; lateral lobes elliptic, rounded; mid-lobe dividing around the middle into two oblanceolate, obtuse lobes, the margins a little reflexed; the disc raised a little in the centre forming a rounded ridge; spur slightly sigmoid, parallel with the ovary, 22 -23 × 0.9 -1.1 mm, gradually narrowing towards the apex, the base with a few glandular hairs. Column horizontal, overall c. 5 × 3 mm, with two 2 mm attenuate rostellum arms for 1 3 its length, with a narrow nose-like mid-lobe recurved at the apex, anther loculi ovoid. Pollinia with 1.5 mm long caudicles. Figs 3, 4. RECOGNITION. Cynorkis marianneae is recognised by its long ligulate leaf, few-flowered inflorescence, and flowers with a four-lobed lip with the elliptic lateral lobes with rounded margins, a mid-lobe divided into two oblanceolate, obtuse lobes with the margins a little reflexed, a spur about the same length as the ovary and the column with a narrow, recurved mid-lobe.
There are strong similarities with both Cynorkis flexuosa Lindl. (Lindley 1835: 331) (Fig. 5A) and C. speciosa Ridl. (Ridley 1886: 122) (Fig. 5B): it is likely that it is a natural hybrid of these two common and variable species. All three were found flowering in the same locality, a few paces apart, with C. flexuosa the most common. Table 2 shows a comparison of the three species, measurements for C. flexuosa and C. speciosa are based on averages of 42 specimens from various herbaria and descriptions. Cynorkis marianneae, is similar in general plant habit and size to both species, it shares the overall lip and spur shape with both but has an intermediate petal, lip and spur size between the two. Both putative parents are very variable in colour but they share the green dorsal sepal-petal hood; the lip of C. speciosa is normally palepink to white with an undefined darker pink area at its base, C. flexuosa invariably has a yellow lip with generally a defined dark red-maroon spot at its base, it is therefore possible that the colour of C. marianneae is a combination of these.
Cynorkis marianneae differs from C. speciosa by the fewer and smaller flowers, the smaller petals, lip and slightly shorter spur. The lobes of the lip do not overlap and the lateral lobes are rounded vs angular sinuate, the anterior lobes are obtuse (vs angular) and slightly repand (vs undulate). The column structure is also different, with a narrow recurved mid-lobe of the rostellum (vs a broader truncate one in C. speciosa). It differs from C. flexuosa by its slightly larger flowers with especially the lip and petals over the maximum recorded size of C. flexuosa, it also lacks the yellow colour of the lip which is consistent in C. flexuosa. The spur is sigmoid (vs straight) and over a third longer. The rostellum arms are less deeply divided and the narrow recurved mid-lobe is intermediate between C. flexuosa and C. speciosa.
Cynorkis marmorata is somewhat similar to C. henrici Schltr. (Schlechter 1924: 52), C. ridleyi T. Durand & Schinz (1895: 92) and C. sororia Schltr. (Schlechter 1913: 154) with which it shares the general lip shape, short thin spur and patterned leaves but they all have much larger flowers and bigger ovate leaves. It is closest to C. flabellifera H. Perrier (1951: 144) with which it shares a similar general habit, lip and spur shape but it consistently has a narrower leaf with an up to 7 mm petiole (vs 45 mm), and flowers that are about 1 3 its size, a dorsal sepal that is broadly ovate (vs lanceolate), a lip with an ovate mid-lobe (vs flabellate), C. flabellifera also lacks the serrate leaf margins and has purple-white flowers and has only been found in Antsiranana province in the far north of Madagascar. DISTRIBUTION. Endemic to Antananarivo province of Madagascar. SPECIMENS EXAMINED. MADAGASCAR. Antananarivo prov., Anjozorobe area, May 1998, 1305 m, Hermans 8257 (holotype K!). HABITAT. In humid evergreen forest, in deep shade, in small scattered clumps, amongst leaf humus, mosses and lichens. c. 1300 m. CONSERVATION STATUS. Cynorkis marmorata is only known from a single unprotected locality in the Analamanga region, Antananarivo province. The species is assessed as Critically Endangered CR based on Criterion D, with the number of mature individuals likely to be fewer than 50 (around 25 plants were seen in one locality), and under criterion B2ab(i,ii,iii) with a continuing decline in the value of the AOO and the EOO estimated to be less than 10 km 2 and the habitat quality due to human activities such as shifting agriculture and forest logging. FLOWERING TIME. April to May. ETYMOLOGY. Referring to its marbled leaf. Erect terrestrial herb up to 15 cm high excluding the inflorescence. Tubers 2 -3, elongate, ovoid, 2 -3 × 0.5 -1 cm, clustered, surface velvety; roots villous, fleshy, wiry c. 1.5 mm in diam. Stem short, 1 -2 cm long. Leaf solitary, broadly lanceolate, caudate at the apex, 52 -75 × 23 -31 mm, attenuate at the apex, with five prominent veins, margins undulate, pale green with the veins a little darker, the mid-vein bordered by a broader dark area, on a long 30 -52 × 3 -7 mm petiole enveloped for a third of its length by a sheath. Inflorescence up to 30 cm long, 1.5 -2 mm in diam., finely pubescent. Peduncle with 4 -6 equally spaced sheaths 6 -8 × 1.4 -1.6 mm. Rachis racemose, c. 5 cm long, loosely 12 -17-flowered. Floral bracts lanceolate, acuminate, irregularly spinose at the margins and along the mid-vein, bright purple when young, becoming reddish-brown with age. Flowers porrect, spreading, c. 10 × 15 mm, pale pinkish-white with much darker purple-magenta markings, a pale pinkish-white dorsal sepal, lateral sepals with parallel dark purple-magenta bands, sometimes fused into one, petals with purple margins, a lip with small purple spots at the base and several triangular spots alongside the paler central vein, a spur with a darker purple tip, rostellum arms edged purple, and purplishred anther loculi. Pedicel with ovary fusiform, 13 -14.5 × 1.8 -1.9 mm, hirsute, white. Dorsal sepal ovate, 4.1 -4.3 × 1.9 -2 mm forming an arching hood over the column with the petals, the apical part narrowed, the exterior longly and densely hirsute. Lateral sepals spreading, parallel with the lip, ovate-acute, 5.8 -6 × 3.1 -3.2 mm, margins incurved, hirsute on the exterior. Petals partly covered by the dorsal hood, oblong-lanceolate, 3.2 -3.3 × 1.1 -1.2 mm, the apex with a small auricle, glabrous. Lip 5-lobed, 6.3 -6.5 × 4.9 -5 mm, the basal lobes small, rounded deltate, the lateral lobes strongly attenuate-angular, incurved, the mid-lobe strongly attenuate-angular recurved at the tip, the disk with a longitudinal raised ridge along its length; spur 8.9 -9.1 × 2.1 -2.3 mm, in the basal 2 3 parallel to the ovary, narrowing, hirsute, then abruptly narrowed, descending and glabrous. Column angular 3.2 -3.3 × 2.4 -2.5 mm, with two 3 mm rostellum arms for over half its length, with a small nose-like midlobe, unevenly obovoid-auricular staminodes towards the base, anther loculi elongate. Pollinia finely granular, c. 3.2 mm long including the long caudicle. Figs 8, 9. RECOGNITION. Cynorkis murex is recognised by its single broadly lanceolate leaf on a petiole almost as long as the blade, its tall loosely racemose inflorescence, and hirsute, brightly coloured flowers with a 5-lobed lip and a descending, angular spur.
Its closest relative is undoubtedly Cynorkis densserpens Hermans & P.J.Cribb (2014: 1) (Fig. 10), described recently from the same area: it shares the plant habit, some of the floral characteristics, and it also flowers at the same time. The new species is very different in that the leaf margins are undulate and entire (vs serrate). The lip is consistently smaller and has rounded-deltate (vs auriculate) basal lobes, strongly attenuate-angular lateral lobes and mid-lobe (vs rounded-obtuse), an angular, descending spur (vs ascending, subulate), it is also a little shorter, 3 mm long rostellum arms (vs 2 mm) and staminodes that are a different shape (they are compared in Table 3). The colour of the flowers is also consistently and considerably different. DISTRIBUTION. Endemic to the Andasibe area in Toamasina province in Eastern Madagascar. SPECIMENS EXAMINED. MADAGASCAR. Toamasina prov., near Andasibe, c. 1150m, May 1996 (holotype K!). HABITAT. In humid evergreen forest, on wooded banks near small streams, in moist humus, in dappled shade. c. 1150 m. CONSERVATION STATUS. Cynorkis murex is endemic to Madagascar and distributed in Alaotra-Mangoro region in Toamasina province. The value of the area of occupancy (AOO) is estimated to be less than 10 km 2 . The species is located outside protected areas. In addition, the EOO, the AOO and the habitat of the species are suffering a continuing decline due to shifting agriculture. It is therefore assessed as E n d a n g e r e d ( E N ) . F u r t h e r r e s e a r c h i s recommended, particularly on population size of this species. FLOWERING TIME. May. ETYMOLOGY. Referring to Murex, a genus of molluscs, often with a prickly exterior, once used to produce the  The identity of Cynorkis frappieri and C. raymondiana Cynorkis frappieri Schltr. (Schlechter 1915: 400)  Small squat herb up to 7 cm high excluding the inflorescence. Tubers 1 -2, clustered, ovoid, 1 -2 × 1.3 -1.8 mm, woolly on the exterior; roots villous, wiry, c. 1 mm in diam. Leaves 2 -3, flat, radical, ovate to lanceolate, 3.7 -8.2 × 1 -2.8 cm, with a very short conduplicate petiole attenuate at the tip, margins entire, green. Inflorescence erect, racemose, up to 22 cm long, glabrous, green with up to 13 flowers but generally fewer. Peduncle slender, 1.5 -2 mm in diam., over 2 3 the length of the inflorescence, with 3 -5 distant lanceolate peduncle sheaths, 5 -12 × 1.1 -2.2 mm, the basal one longer and more acuminate than the others. Rachis laxly flowered, 2 -6 cm. Floral bracts lanceolate, acuminate, 3.8 -4.9 × 1.3 -1.5 mm. Flowers very small for the genus, erect to arching, up to 7 × 6 mm, glabrous, crystalline white with the exterior of the sepals more or less tinted pinkish green, the lip with up to 6, more or less merging, magenta spots, with magenta-marked basal lobes, and yellow pollinia, (Szelengowicz & Tamon (2013: 270) report forms without distinct spots on the flowers and other forms with an overall pink to mauve pigmentation). Said to be scented of goat (d'odeur hircine) by Frappier (1895: 238) but this has not been verified in the field. Pedicel with ovary fusiform, 6 -10 × 1 -1.2 mm, glabrous, green. Dorsal sepal forming a tight hood with the petals, broadly ovate, obtuse, concave, 2.1 -3 × 1.5 -1.8 mm. Lateral sepals spreading, ovate, concave, 2.8 -3.0 × 1.5 -1.8 mm. Petals lanceolate to elliptic, acute, 2 -2.5 × 0.9 -1.2 mm. Lip obcordate, unequally 5-lobed, 3.2 -4 × 2.5 -2.9  mm, the anterior lobe triangular acute, the lateral lobes a little larger, obovate obtuse, the basal lobes small, triangular acute; spur thickened in the lower half to club-shaped, 1.5 -1.8 × 0.4 -0.6 mm. Column in a horizontal blade to somewhat ascending, 1 -1.7 × 1 -1.1 mm, anther bilobed, midlobe of the rostellum and staminodes small, rounded, lateral lobes of the rostellum bidentate at the front, with the midlobe of the rostellum appearing tridentate, the pollinia ending in a distinct viscidium. Figs 11, 12. RECOGNITION. With its slender plant habit, laxly fewflowered inflorescence, small flowers and rostellum with a short toothed horizontal blade Cynorkis frappieri belongs in sect. Hemiperis (Frapp. ex Cordem.) Perrier in Arch. Bot. Bull. Mens. 5 (1931: 36 unpublished); Perrier (1939: 74). It is recognised by its glabrous habit and flowers, two or rarely three ovate to lanceolate leaves flattened on the ground, a long peduncle at least 2 3 the length of the inflorescence, and small white with distinct magenta spotted flowers with a    Mauritius. The extent of occurrence (EOO) is estimated to be more than 20,000 km 2 . The species is not recorded in any Protected Areas in Madagascar it is therefore inferred that most of its subpopulations are threatened by habitat destruction due to slash and burn agriculture (Tavy) and fires set for land-clearing and pastureland. The species is therefore assessed as Near Threatened (NT). FLOWERING TIME. Madagascar Perrier (1931: 48), mentioned by Perrier in the Flore de Madagascar (1939: 97), was never effectively published but later validated, as explained in Hermans et al. (2007: 290) . Perrier (1939: 97) Szlachetko & Kras (2006: 145) in their unsubstantiated fragmentation of the genus invalidly transferred Cynorkis raymondiana to the genus Bicornella (Lindley 1835: 335) and incorrectly referred to Perrier's basionym as published in Archivio Botanico per la Sistematica, Fitogeografia e Genetica 5: 48 (1931).
The identity of Cynorkis gaesiformis, C. galeata, C. nutans C. stenoglossa Terrestrial, epiphytic or rarely lithophytic herb up to 30 cm tall including the inflorescence, with 3 -6 elongate pubescent tubers 1 -4.5 × 0.5 -1.5 cm; roots dense, woolly. Leaves 1 or rarely 2, radical, broadly elliptic to oblong, 4.5 -19.5 × 2.5 -6.2 cm, tip acuminate, narrowed into a more or less attenuate petiole at the base, blade flat, arching towards the tip, green with the veins often a little paler, with a thin sheath enveloping the base, acuminate to caudate, 1 -3 cm long. Inflorescence erect to divergent, 6 -26 cm tall, with up to 30 flowers. Peduncle about 2 3 of the inflorescence, 3 -4 mm in diam., densely hirsute along its length, generally with a prominent lower peduncle sheath 12 -42 × 3 -19 mm and 2 -3 additional sheaths 6 -12 × 2.5 -3.2 mm. Rachis subdensely to densely racemose, often opening in succession with the lower ones fading before the upper ones open. Floral bracts narrowly lanceolate, 4.8 -8.9 × 1.5 -2.1 mm, attenuate, hirsute on the exterior. Flowers variable in size, up to 16 × 29 mm, very variable in colour, ranging from pale pink to deep mauve-purple, some forms having pink, lilac to purple sepals, lip and petals, the anther loculi brownish-purple. Pedicel with ovary fusiform, 12 -24 × 1.7 -3.5 mm, densely hirsute, white to pink. Dorsal sepal lanceolate, 4.5 -8.1 × 2 -3.3 mm, helmet-shaped, the tip recurved, forming a tight hood with the petals, hirsute on the exterior. Lateral sepals broadly lanceolate to ovate, 7.7 -17.3 × 4 -7.9 mm, flat, asymmetric, spreading, attenuate, often hirsute on the exterior, especially towards the attenuate base. Petals adnate to the dorsal sepal, lanceolate, 4.5 -8.4 × 2.2 -3.9 mm, expanded at the outer margin towards the base becoming broadly falcate and from that point narrowing towards the obtuse apex. Lip ligulate to narrowly lanceolate, 5.3 -10.1 × 1.1 -2.9 mm, a little narrowed toward the middle, with more or less pronounced lateral lobes near the base ranging from minutely expanded through lobular to dentate, tip sub-acute to attenuate; spur curved to sigmoid, 8.5 -19.3 × 1.9 -3.1 mm, parallel with the ovary first becoming more pendent, tubular at the base then expanded, then narrowing into a more or less curved tip. Column 2 -3.9 × 1.7 -2.8 mm, with distinct rostellum arms, the anther loculi subglobose, staminodes small, slightly protruding below the lateral lobes of the rostellum, rostellum deeply notched in the middle, mid-lobe reduced to a small swollen blade, lateral arms c. 1 mm long, thick, incurved, the caudicles of the pollinia ending in a distinct viscidium. Fig. 13. RECOGNITION. With its small mid-lobe of the rostellum and distinct elongate anther canals, Cynorkis nutans belongs in sect. Imerinorchis H.Perrier ex Hermans (Hermans et al. 2007: 290). It is recognised by its large leaf, tall hirsute inflorescence with a prominent lower peduncle sheath, the ovary and flowers hirsute on the exterior, the dorsal sepal and the petals forming a hood over the column, the flat, spreading, asymmetric, broadly lanceolate to ovate lateral sepals, and ligulate lip with small lobes at the base and a curved spur which is thickened around the middle.
It is similar in habit and lip shape to Cynorkis zaratananae Schltr. (Schlechter 1924: 75) but that species has a longer leaf petiole, slightly smaller flowers by c. 1 3 and shorter spur, inflated at the tip (vs narrowing). It has a similar hirsute inflorescence and flowers and a similar lip shape to C. rosellata (Thouars) Bosser (1997: 188) and C. saxicola Schltr. (Schlechter 1924: 70) but those species have several leaves arranged in a rosette (vs single), slightly smaller flowers with a shorter spur half the length of the ovary (vs about the same length) which is thickened towards the tip (vs narrowing). (P00102297). In 1951 Perrier (: 146) described C. gaesiformis from a collection by Decary in the Madagascan Highlands, the type sheet was annotated in 1950 as 'Cynosorchis caesumiformis sp. nov'. In 2005 Szlachetko transferred Cynorkis galeata, C. nutans and C. stenoglossa to his segregate genus Imerinorchis but did not include C. gaesiformis in the transfer.
Several authors and botanists have already indicated some similarity between Cynorkis gaesiformis, C. galeata, C. nutans and C. stenoglossa: the BM type specimen of C. galeata (Humblot 209) was annotated by Ridley as 'Habenaria nutans Ridley!'; Kraenzlin (1901: 920 & 923) listed 'Cynorkis galeata Rchb.f. huc Habenaria nutans Ridley' under his Species subdubiae v. dubiae, Bosser determined the Decary 18419 type specimen of C. gaesiformis as C. nutans in 1968 andHervouet (2018: 299) remarked that C. galeata, C. nutans and C. stenoglossa are to be compared. Following field observations and comparing all the available herbarium material identified under these four names and their varieties it has become clear that they are all part of one variable species with Ridley's C. nutans having priority over Reichenbach's C. galeata by just a few months, C. gaesiformis and C. stenoglossa are later additions of 1893 and 1951 respectively. Table 4 shows the great range in size of plant and flower segments of the different species and varieties but also indicates their overlapping characteristics; field observations have also shown great variations within colonies. Plants consistently have a single (rarely two), comparatively large leaf, a long hirsute inflorescence, an hirsute ovary and exterior of the flower, broad flat lateral sepals which are spreading and asymmetric, a ligulate lip which has variable but always small lobes at the base, a more or less sigmoid spur which is thickened in the middle and a rostellum with a reduced midlobe and separate incurved arms. Colour of the flowers is also very variable and may have led to some of the proliferation of names; field observations and photographic records have shown that there are a number of consistently different colour forms but it has also shown that the diverse colour variations are mixed within colonies and localities (see Fig. 13).
Following its general plant and flower morphology, Cynorkis inermis (Thouars) Hermans & P.J. Cribb (Hermans et al. 2017: 28) from Mauritius and Réunion could also be considered part of this species but the lack of a spur makes it distinct. A few plants of C. inermis have been found on Réunion that have a short spur or remnant thereof (Bernet 2010: 122 &pers. comm. andSzelengowicz &Tamon 2013: 277) but the lack or reduction of a spur indicates a change in pollinator interaction and its endemism to the islands of Mauritius and Réunion warrant its recognition as a distinct species. The genetics and , enclosed by 1 -2 leaf-like sheaths and the basal leaf petiole; 3 -4 large distant opposite leaves, followed by 2 -4 leaf-like sheaths above, decreasing in size. Leaves obliquely lanceolate, narrowed at the base into a long funnelshaped petiole annular at the base, with a strong midvein and 2 -3 parallel veins, 5 -12 cm long, 2.5 -6.5 cm wide, leaves and leaf sheaths pale green spotted with brownish-maroon. Inflorescence emerging from the centre of the developed growth, dark green becoming paler towards the rachis, hirsute towards the apex, up to 40 cm, 1.9 -3.5 mm in diam., with 2 -3 lanceolate leaf-like sheaths strongly amplectant towards the base, caudate at the tip, c.  HABITAT. In full sun on rock, in a thin layer of humus and moss. Short evergreen scrubland with Kalanchoe spp. and other geophytes. It is interesting to note that the spotted foliage of Cynorkis mammuthus is somewhat similar to that of Kalanchoe gastonis-bonnieri R. Hamet & H.Perrier (1912: 364) (Crassulaceae), with which it grows together. CONSERVATION STATUS. Cynorkis mammuthus is endemic to Madagascar, restricted to the Sofia region in Mahajanga province at low elevation. It is only known from a few individuals, the Area of Occupancy is estimated to be less than 500 km 2 , in three unprotected areas. The species is threatened by habitat degradation due to frequent fires. Cynorkis mammuthus is therefore assessed as Endangered EN, according to the IUCN Red List Categories and Criteria. Further research is needed to check the population size and status.
Rapanarivo, head of the flora department at PBZT Antananarivo, for his permission to use the collection at the PBZT herbarium and for providing the necessary collecting authorisation.
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