New species and nomenclatural changes in Bulbophyllum (Orchidaceae) from Madagascar

Six new species: Bulbophyllum caniceps, B. cochinealloides, B. fierenanaense, B. geminiflorum, B. oenanthum and B. rudolphus are described for the first time. The identity and nomenclature of Bulbophyllum cylindrocarpum is discussed and its var. andringitrense is recognised at species rank as B. jeanbosseri. Bulbophyllum aubrevillei and B. kieneri are compared with the latter becoming a synonym. The history and identities of Bulbophyllum pentastichum vs B. quadrifarium are clarified and the necessary taxonomic changes and type selections are made. A new sect. Inversiflora is formally described.


Introduction
Bulbophyllum Thouars (1822) is one of the largest genera in the Orchidaceae (subfamily Epidendroideae tribe Malaxideae subtribe Dendrobiinae) (Chase et al. 2015), comprising just over 2000 species (Vermeulen et al. 2018: 31) and has a pantropical distribution (Govaerts 2016). Recent molecular phylogenetic studies suggest that Bulbophyllum originated in the Asia-Pacific region during the early Miocene before reaching the tropical regions of Madagascar, Africa and S America in the mid to late Miocene (Gamisch et al. 2015;Gamisch & Comes 2019). One of the main diversification centres is in the Madagascar region with over 200 largely endemic species ; Gravendeel in Pridgeon et al. 2014: 7).
Since the major work on the orchid flora of Madagascar by Schlechter and Perrier de la Bâthie (henceforth Perrier) (Schlechter 1924;Perrier 1937 a number of novelties in the genus have been described by Bosser (1965Bosser ( , 1969Bosser ( , 1971Bosser ( , 1989Bosser ( , 2000Bosser ( , 2004, Bosser & Cribb (2001) and Fischer et al. (2007aFischer et al. ( , b, 2009) with a broad outline revision of the Madagascan sections by Fischer & Vermeulen (in Pridgeon et al. 2014: 15 -19). Recent research into the phylogeny and morphology of the genus (at Salzburg and Vienna), taxonomic research (at Vienna and Kew) and fieldwork (by the Botanical Garden of the University of Vienna, University of Salzburg, PBZT Antananarivo and Royal Botanic Gardens, Kew, have resulted in the recognition of a number of new species and a better understanding of their nomenclature and genetic relationships. A new phylogenetic study based on five chloroplast and three nuclear regions of c. 180 Madagascan Bulbophyllum species is currently being prepared (Gamisch et al. unpublished). During this work six new species have been identified and several changes in nomenclature have become necessary.

IUCN Red List assessments
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). Ambalavao, Jan. 2007, Sieder, Stütz & Andriantiana FS4073 (holotype SZU!).
RECOGNITION. Bulbophyllum caniceps is recognised by the small flattened pseudobulbs, the single obovate leaf from the centre of the pseudobulbs, the thin fewflowered inflorescence, the small flowers with lanceolate, longly caudate-falcate sepals, broadly lanceolate petals, a rounded, recurved lip with an obtuse tip and the papillose base, the lip margin, basal edge of the sepals, tip of the petals and floral bract serratelaciniate to hirsute, the long falcate stelidia and anther with a tiny lobule. DISTRIBUTION HABITAT. Plants partly submerged in moss, humid evergreen forest, around 1000 m. CONSERVATION STATUS. This species is endemic to Madagascar, distributed in Haute-Matsiatra region, Fianarantsoa. It is likely to be Endangered (EN), according to the IUCN Red List Categories and Criteria. It is found in only one confirmed locality, having a provisional status of protection as a private reserve. The area of occupancy AOO is estimated to be 8 km 2 , the extent of occurrence EOO cannot be estimated, and two defined locations face major threats from human activity that cause the continuing decline of the habitat quality and the AOO of the species. This species is therefore assessed as Endangered under criterion B2ab(ii,iii). ETYMOLOGY. The name refers to the resemblance of the flower to the head of a fluffy dog with a red tongue. PHENOLOGY. January. N O T E S . As with many small few-fl o w e r e d Bulbophyllum it is difficult to place the new species in any section circumscribed by Schlechter (1924) and more recently discussed by Fischer et al. (2007b). It has some of the characteristics (small single-leafed plant with floral parts hairy) of sect. Pantobleparon Schltr. but it lacks the short inflorescence. In plant habit and flower morphology it is also close to some species in sect. Lichenophylax Schltr. but has a single leaf and long (vs short) stelidia. With its small single-leafed pseudobulbs, a slender few-flowered rachis, caudate sepals and ciliate lip, the most appropriate section for the species is sect. Trichopus Schltr. as redefined by Fischer et al. (2007b: 6). This impression is confirmed by genetic data which place the new species, into a well-supported and relatively well-resolved clade comprising species of sect. Trichopus and Pantobleparon (Gamisch et al. unpublished Large creeping epiphytic plant up to 25 cm tall excluding the inflorescence, on a short repent rhizome (4 -5 mm in diam.) hidden beneath the pseudobulbs, rhizome sheaths membranous; roots wiry, glabrous, forming a dense mass beneath the plant, c. 2 mm in diam. Pseudobulbs dense, overlapping each other by about 1 = 3, broadly ovoid to orbicular, very compressed, 2.3 -3 × 2.5 -3.3 cm, c. 8 -12 mm thick, bifoliate, surface lustrous, more or less rugose, yellowish-green becoming yellow with age, a few thin bracts at the base. Leaves spreading, flat with a shallow mid-vein, base shortly petiolate, set within a thickened ring, oblong to lanceolate, tip rounded, 4 -10 × 0.8 -2 cm, coriaceous, green. Inflorescence erect, rachis slightly curved, up to 44 cm long, with c. 50 flowers. Peduncle emerging from below the pseudobulbs where the base is covered by 2 -3 sheaths, terete, 28 -30 cm long, c. 3 mm in diam., with 5 -7 tubular peduncle sheaths c. 15 mm long. Rachis rather densely flowered (3 -5 mm apart in each row) in 4 rows in an indistinct spiral, opening in succession from the base, 16 -18 cm long, a little thicker than the peduncle, c. 5 mm in diam., hollowed at the inset of the ovaries, roundly ridged behind each flower, yellowishgreen to pink, marked with paler streaks. Floral bracts scarious, lanceolate-triangular, attenuate, 5 -6.5 × 1.8 -2.1 mm. Flowers non-resupinate, becoming recurved to the rachis on opening, c. 12 × 12 mm, petals and sepals yellow marked with pale carmine, darker on the exterior, with 2 -3 darker carmine red longitudinal lines, petals pale yellow, lip yellow, the margins carmine red, spotted red on the disk, more densely along the margins, column white spotted pink, anther white. Pedicel and ovary subsessile, turbinate, with rounded ribs, 2.8 -3 × 0.9 -1.2 mm, dark pink. Dorsal sepal linear-lanceolate, the base concave, attenuate, arching forward, 5.9 -6.8 × 1.1 -1.4 mm. Lateral sepals lanceolate, falcate, apex longly  attenuate, 6.2 -6.7 × 2 -2.2 mm, adnate with the column foot forming a 1 -1.5 mm mentum. Petals lanceolatenarrowly triangular, parallel with the column, 1.9 -2.1 × 0.3 -0.4 mm, margins entire. Lip fleshy, lingulate to oblong, 3 -3.2 × 1.1 -1.2 mm, the base auriculate, the margins finely verrucose in the basal third, the disc roundly convex, the tip acute, flattened, slightly curved forward. Column arching, 2.2 -2.5 × 1.3 -1.8 mm, with a subulate mid-lobe, prominent falcate stelidia c. 1 mm long, roundly lobed towards the base. Anther with two distinct orbicular chambers, 0.9 -1 × 0.8 -0.9 mm, with a distinct triangular lobe at the tip. Pollinia 2, ovoid, c. 0.5 mm. Figs 3, 4.
RECOGNITION . Bulbophyllum cochinealloides is characterised by its overlapping ovoid to orbicular flattened pseudobulbs, the long inflorescence with up to 50 non-resupinate flowers, the thickened, roundly ridged rachis, the lingulate-oblanceolate lip with auriculate basal wings, convex disk, finely verrucose margins, the long stelidia and the mid-lobe of the column and the lobed anther. DISTRIBUTION. Endemic to Madagascar, Antananarivo province. Known from the Type only. HABITAT. Humid evergreen forest, c. 1200 m. CONSERVATION STATUS. This species is an endemic orchid of Madagascar, only known from a cultivated individual from the Analamanga region in 2009. It is currently considered to be Data Deficient (DD), according to the IUCN Red List Categories and Criteria with incomplete information on the distribution, population size and trend of this species. Further research is needed to check the population status, threats, habitat and distribution. PHENOLOGY. September to October. ETYMOLOGY. Named for the carmine red colouration of its flowers in reference to the dye cochineal which is extracted from scale insects of the genus Dactylopius which cling to the substrate of their host plant, as do the pseudobulbs of this orchid. NOTES. Bulbophyllum cochinealloides shares its flattened pseudobulbs, a long inflorescence and overall flower structure with B. cardiobulbum Bosser (Fig. 3D) and B. uroplatoides Hermans & G.A.Fisch. (Fig. 3C) but it differs from both in its longer rachis which has more densely placed and more numerous flowers. The flowers are almost half the size of those of B. cardiobulbum and the lip is lingulate-oblanceolate (vs more spathulate), it is also slightly smaller than B. uroplatoides, especially the lip which is almost half the size and has a rounded disk of the lip (vs deeply longitudinally furrowed). See comparison in Table 1.
Phylogenetically the new species is closest related to Bulbophyllum uroplatoides and Bulbophyllum cardiobulbum as a part of a well-supported sub-lineage, distinct from the remaining Madagascan Bulbophyllum clades (Gamisch et al. unpublished). Due to its distinct phylogenetic position and its blend of morphological characters it was proposed (Fischer et al. 2007b;Gamisch et al. 2015) that B. cardiobulbum, which was originally assigned to sect. Calamaria Schltr. by Bosser (1965: 396) should be placed into a new section together with B. uroplatoides (Fischer et al. 2007b). For this purpose, a new sect. Inversiflora G.A.Fisch. & P.J. Cribb 'in prep' (in Pridgeon et al. 2014: 17) has been suggested but, to date, not formally described, it is described below. The new species is therefore placed into the same section as B. cardiobulbum, based on morphological and phylogenetic evidence. Slender epiphytic plant up to 15 cm tall excluding the inflorescence, scrambling on a long rhizome with the pseudobulbs c. 2.5 cm apart, at an almost 45 degree angle to the substrate, 2 -3 mm in diam., partly covered by thin scales: roots wiry, c. 1 mm in diam. Pseudobulbs bifoliate, cylindrical, a little widened at the base, longitudinally ridged, 3.5 -8.5 cm × 5 -9 mm, purple-brown, with 2 -3 membranous tubular basal sheaths, attenuate at the tip, 10 -20 mm long. Leaves obliquely erect, narrowly ligulate, flat to somewhat revolute, subsessile to shortly petiolate, 5 -7 cm × 8 -12 mm, apex unequally incised with one part rounded, the other dentate. Inflorescence pendent to arching, somewhat curved, 9 -18 cm long, with up to 16 flowers but generally fewer, pinkish-purple. Peduncle slender, becoming a little thicker towards the apex, about half the length of the inflorescence, with 4 -6 thin scarious bracts c. 5 mm long. Rachis a little thicker than the peduncle, loosely racemose, the flowers 4 -7 mm apart. Floral bracts triangular, attenuate, 2.5 -4 × 1.2 -2 mm, a little rugose. Flowers spreading, opening basipetally, c. 15 × 16 mm, the dorsal sepal creamywhite with 5 burgundy red longitudinal bands along the veins, lateral sepals creamy-white splashed with burgundy, creamy-white with 3 broad longitudinal deep burgundy bands along the veins, lip reddish pink, the upper surface darker, the epichile verrucae brownish green. Pedicel and ovary ovoid, slightly grooved, a little punctate, 1.5 -3 × 1.2 -3 mm, pink. Dorsal sepal lanceolate, attenuate, obtuse at the base, 7.7 -10 × 2.1 -3.1 mm. Lateral sepals ovate-lanceolate, strongly acuminate to caudate at the tip, 7.3 -8.3 × 3.2 -4 mm. Petals elliptic, truncate at the apex, somewhat curved, 3.1 -4.1 × 1.3 -1.9 mm. Lip very motile, attached with a thin filament to the column foot, narrowly lingulate, 5.8 -6.5 × 1.5 -2.1 mm, narrowed towards the base with 2 auriculate lobes, epichile concave, hollowed, minutely verrucose, the margins   This species is endemic to Madagascar, distributed in Atsinanana region, Toamasina province. It is known from four herbarium specimens collected in 2008 representing four subpopulations in unprotected areas. This species is considered to be threatened by habitat destruction due to grazing and frequent fires. Based on two defined threat locations, the area of occupancy AOO is likely less than 500 km 2 , the extent of occurrence EOO estimated to be less than 5,000 km 2 and the continuing decline in the EOO, AOO and the habitat quality, this species is therefore assessed as Endangered (EN) under criterion B1ab(i,ii,iii)+B2ab(i,ii,iii). PHENOLOGY. December. ETYMOLOGY. Named for the area where the species was discovered. NOTES. With a finely verrucose hollowed epichile and the long acicular stelidia, Bulbophyllum fierenanaense belongs in Bulbophyllum sect. Elasmatopus Schltr. In the section it shares the sepal shape and long lingulate lip with B. oxycalyx Schltr. but the latter has much shorter ovate (vs cylindrical) pseudobulbs, oblong (vs narrowly ligulate) leaves, and the margins of the sepals are serrate (vs glabrous). Morphologically it is closest to B. amphorimorphum H.  which are also closely related phylogenetically in a well-supported group (Gamisch et al. unpublished). Table 2 compares their main characteristics. In overal l fl oral morphology, it is closest to B. amphorimorphum but in the latter the pseudobulbs are much shorter and long-ovoid (vs cylindrical) and they are unifoliate (vs bifoliate), the lip is also more sigmoid and the stelidia shorter. Although the pseudobulbs are generally much longer, more evenly cylindrical and the inflorescence longer than the plant, it is similar in habit to B. aubrevillei but in that species the sepals are shorter and acute (vs lanceolate-attenuate) and the lip is ovate (vs lingulate) and less than twice as long than wide (vs three times longer than wide).
The flowers of the new species appear to open basipetally, from tip to base of the inflorescence. This seems more common in species in sect. Small (8 -20 × 2 -4 mm) spreading epiphytic plant on a long verrucose, silvery white rhizome, c. 1.5 mm in diam. Pseudobulbs elliptic to ovoid, 7 -9.5 × 3 -4.5 mm, smooth with a few rounded raised ridges, with 1 -2 membranous basal sheaths, reddish-green, with two apical leaves. Leaves narrowly lanceolate, 10 -13 × 3 -6.5 mm, with a short 2 -4 mm petiole at the base, the   margins attenuate and a little erose, the dorsal midvein a little keeled and extended into a thorn-like extension at the apex, green, becoming reddish-green underneath when mature. Inflorescence short, emerging from the base of the mature pseudobulbs, slightly arching, up to 15 mm long, with 2 (or rarely 1) flowers. Peduncle terete, 5 -7 × 1.2 -1.5 mm, becoming thicker towards the base of the first flower, the basal third with 2rarely 3 long-acuminate sheaths, dorsally keeled, erose. Rachis very short, densely flowered. Floral bracts thin, lanceolate, longly acuminate, 1.9 -3.2 × 1.3 -1.6 mm, enclosing the pedicellate ovary and overlapping the base of the flower. Flowers very small, normally in pairs backing onto each other, overall c. 4 × 2 mm, yellowish-green, strongly marked with burgundy-pink, sepals and petals densely spotted burgundy with the tips white, the lip pink at the base, yellow in the anterior half, the basal wings burgundy, anther and pollen yellow-white.
Pedicel and ovary ovoid, 1. Ploiarium are small and two-flowered with the flowers borne back to back. The thorn-like extension of the leaf tip is also rare in Bulbophyllum species from the Madagascan region but it is likely that this feature, together with the erose margin of the leaf, was missed and therefore usually not noted by authors working with dried material only. It has also been observed in B. oenanthum, described below but they share no other characteristics. There are a few other small species in the section with a few-flowered inflorescence shorter than the plant and a ventricose rounded lip but they all have a habit and leaves more or less twice the size of those of the new species. It shares a somewhat similar plant habit, lip and stelidia with B. rubiginosum Schltr. but that has oblong or lanceolate-ligulate leaves (vs narrowly lanceolate), the inflorescence has more than four flowers (vs two) and the dorsal sepal is oblong (vs ovate). It shares some features with B. aggregatum Bosser, especially the lip but that has more than six flowers (vs two) and the sepals are distinctly papillose (vs glabrous). The plant habit and small flowers might also be confused with B. insolitum Bosser but the latter's pseudobulbs are more flattened, the leaves oval to oblong (vs narrowly lanceolate), the lateral sepals serrate (vs entire), the lip three-lobed (vs subglobose) and the stelidia bidentate (vs tridentate). Epiphytic plant on a short branching rhizome 5 -15 mm long in-between the pseudobulbs, c. 1 mm in diam., covered in sheaths; roots wiry, glabrous, c. 0.5 mm in diam.
Pseudobulbs elliptic to ovoid, triangular in cross-section, somewhat winged, 6 -20 × 4 -12 mm, smooth with 2 -3 rounded grooves, bifoliate, a few scarious acuminate bracts towards the base, green marked with brownish-red. Leaves flat, oblong, 15 -49 × 5 -10 mm, acuminate unequally bilobed at the tip, attenuate at the base towards a short 2 -3 mm petiole, the prominent dorsal mid-vein ending in a thorn-like extension, green on the upper surface, redpurple underneath, mid-vein and margins darker. Inflorescence arching at first then pendent, extending as the flowers develop, up to 65 mm long, with up to 15 flowers. Peduncle round, substantially thickened towards the apex, with 2 -3 nodes, peduncle sheaths short, thin amplexicaul, 1 -3 mm long. Rachis densely-flowered, thickened, triangular in cross-section, about ¾ of the inflorescence length, hollowed beneath each flower and the floral bracts at first overlapping then forming a seamless series of hoods along the rachis as the flowers open, pale green, tinted red along the ridge of the floral bracts. Floral bracts fleshy, 3.4 -7 × 1.9 -3 mm, forming a hood over part of the flower, with a distinct dorsally keeled to almost sharply winged ridge, apiculate at the tip, triangular, roundly lobed at the base, forming a distinct zig-zag pattern in old inflorescences.
Flowers flat against the rachis, c. 6 -7.5 × 2.5 -3 mm, ochreyellow, the sepals densely suffused with brownish-pink, lip and petals yellow. Pedicel and ovary rounded, narrowing towards the base, 1.8 -2 × 1.    The epithet firstly refers to the wine-red colouration of the bracts and flowers and secondly to the bird genus Oenanthe (Wheatears), indirectly referring to the wheat-ear appearance of the rachis. NOTES. The new species is best placed in sect. Ploiarium; a section defined morphologically by its bifoliate pseudobulbs and flowers with more or less fused lateral sepals forming a platform beneath the lip and with lateral keels. It largely conforms to these criteria except that the lateral sepals are only fused during the beginning of their development and become separate on maturity. Phylogenetically it is nested, as part of a well-supported yet poorly resolved subclade (comprising c. 34 species), in the strongly supported sect. Ploiarium (Gamisch et al. unpublished data). With its thickened peduncle and prominent floral bracts it is similar to Bulbophyllum pleiopterum Schltr. from the same area but that species is much larger with the leaves and inflorescence at least double the size, and it has flowers with lateral sepals that are fused, linear-ligulate petals (vs lanceolate-ovate), a lip of a different shape and acuminate stelidia (vs Morphologically it is closest to the phylogenetically distantly related Bulbophyllum labatii Bosser, also from the Masoala peninsula: they are approximately of the same size, have prominent floral bracts and share the unusual way the lateral sepals become divergent. Bulbophyllum labatii has a longer rhizome, much longer inflorescence (40 -60 cm vs 6 -7 cm) with double the number of flowers, the floral bracts are obtuse (vs apiculate), the lip is convex (vs concave) and the stelidia are distinctly three-lobed (vs indistinctly lobed), and the flowers are yellow (vs ochre extensively suffused with red).
Even though the relationships of the new species are not fully resolved, unpublished research by Gamisch et al., shows that the strongest genetic links seems to be with Bulbophyllum toilliezae Bosser and, to a lesser extent, with B. leptochlamys Schltr. With B. toilliezae it shares the small verrucose lip but the plant of this species is much more robust, the inflorescence longer, the floral bracts broader, the sepals and petals at least three times bigger, the lateral sepals are fused along their entire length and the stelidia have a different shape, the colour of the flowers is clear yellow (vs suffused with red). With B. leptochlamys it shares a small lip and general habit but differs by its shorter oblong leaves (vs linear-ligulate), the thick apiculate triangular floral bracts (vs thin oval) and the small bilobed stelidia (vs long subfalcate). Diminutive epiphytic plant on a thin ramose, repent rhizome c. 1 mm in diam., thickening towards the base of the pseudobulbs; roots smooth, rounded with a few short scales, c. 0.5 mm in diam. Pseudobulbs 2-leaved, a few millimetres apart, flattened, ovoid to globose, 3 -4.5 mm long × 1.2 -1.8 mm wide, green, ridged, the base with some membranous sheaths. Leaves ovate, apex acute, 3.5 -5.2 × 2.1 -2.8 mm, subsessile towards the base, shortly petiolate, set toward the end of the pseudobulb and within a slight depression, greyishgreen with the central and lateral veins dark green. Inflorescence from the base of the pseudobulbs, de-scending, single-flowered at the apex, up to 33 mm long. Peduncle thin, rigid, 25 -30 × 0.2 -0.3 mm, thickening towards the base of the pedicellate ovary, with two membranous, imbricate sheaths 2.8 -3.2 mm long, minutely verrucose all over. Floral bract membranous, broadly lanceolate, 1.4 -1.6 × 0.9 -1 mm, covering the ovary. Flower almost sessile, the segments divaricate, c. 6.5 × 7 mm, overall pale yellow, the dorsal sepal with broken red lines along the veins, the lateral sepals burgundy red at the base, fanning out along the veins, petal tips red, lip pale orange, burgundy at the base, column pale yellow, anther area bright red. Pedicel and ovary very short, slightly ridged, c. 1.3 × 1 mm. Dorsal sepal broadly lanceolate, attenuate, recurved towards the apex, 10 -10.1 × 3.8 -3.9 mm. Lateral sepals lanceolatefalcate, 9.1 -9.3 × 2.9 -3 mm, the margins involute. Petals elliptic, roundly retuse at the apex, 2.2 × 1.3 mm. Lip glabrous, broadly lingulate, 2.7 -2.9 × 1.1 -1.2 mm, thickened and rounded at the tip, roundly winged at the base, mobile on the column foot. Column short with a long tapering foot, stelidia shortly bidentate, triangularacuminate, c. 2.2 × 1.1 mm. Anther bilobed, c. 0.4 × 0.5 mm. Pollinia ovoid c. 0.3 × 0.2 mm. Figs 11, 12.

RECOGNITION. Bulbophyllum rudolphus belongs in sect.
Lichenophylax characterised by its tiny habit on a branching rhizome, small ovoid bifoliate pseudobulbs, thin single-flowered inflorescence, fleshy lip and short triangular stelidia. It is typical by the silvery leaves, long needle-like peduncle, sepals without a long acumen, blunt petals, the small lip ( 1 = 3 of the sepals) which is thickened lingulate and the short bidentate stelidia. DISTRIBUTION. Toamasina province, E Madagascar. Known from the type only but there are photographic records from the Marojejy massif in Antsiranana province, N Madagascar (Hervouet 2018: 242). HABITAT. Epiphyte amongst bryophytes in humid evergreen forest, 1150 m. CONSERVATION STATUS. This species is endemic to Madagascar, distributed in Alaotra-Mangoro (Toamasina) and Sava (Antsiranana) regions. It is located in Zahamena Ankeniheny Corridor and may occur in Marojejy Protected Areas. It is known from one threat location. The habitat and the area of occupancy of this species are threatened and in continuing decline by logging, subsistence slash-and-burn farming, grazing and fires. Confirmation of its existence in northern Madagascar could alter its status. Bulbophyllum rudolphus is therefore assessed as Critically Endangered (CR) under criterion B2ab(ii,iii). PHENOLOGY. May. ETYMOLOGY. In reference to the bright red colour of the anther and tip of column reminding us of Rudolph the red-nosed reindeer. NOTES. It is closest to the equally diminutive Bulbophyllum neglectum Bosser which comes from the same area: it has comparable pseudobulbs and some-what similar flowers but the leaves are narrower (linear lanceolate vs ovate), the peduncle shorter (17 mm vs 30 mm), and distinctively coloured flowers (overall yellow-orange with a bright red anther vs overall violet red with a white anther) with sepals about half the length and more longly acuminate, petals that are attenuate (vs blunt) and a triangular lip (vs bluntly lingulate).
It is somewhat similar to Bulbophyllum pandurella Schltr. but that differs by its smaller size and shape of the floral segments and the long, almost 1 mm stelidia (vs minutely triangular).

Bulbophyllum sect. Inversiflora
Bulbophyllum sect. Inversiflora G.A.Fisch., Gamisch & P.J.Cribb sect. nov. Type species: Bulbophyllum cardiobulbum Bosser (1965: 396). Madagascar, Ankeramadinika, J.-P. Peyrot 5 (holotype P!) http://www.ipni.org/urn:lsid:ipni.org:names:77214540-1 Medium-sized epiphytes. Rhizome creeping. Pseudobulbs close together, distinctly laterally flattened, 2-leafed. Inflorescences heteranthous, a many-flowered, elongated raceme with spirally arranged flowers. Rachis thickened, somewhat spindle-shaped. Flowers reflexed, with the lip turned away from the rachis. Sepals free, glabrous abaxially. Petal margins entire, glabrous. Lip mobile, undivided, thick, margins entire, glabrous, verrucose or partly ciliate. Column stelidia rather short, triangular, acute, without a tooth along the lower margin. Anther with a rounded to conical protrusion which overtops the front margin. Kainochilus Schltr.) such as an erect inflorescence, hairs on the lip and laterally flattened two-leaved pseudobulbs (Fischer et al. 2007b). However it differs in several respects: the inflorescence is erect and rigid (vs erect, pendulous or recurved in Lupulina), the pedicel apically droops up to 135 degrees (vs up to 180 degrees in Alcistachys), the flowers are large (vs comparatively small in  Lupulina) and the stelidia have a small tooth along their upper margins (vs no tooth along their upper margins in Alcistachys, Lupulina and Kinethrix). Furthermore, the pseudobulbs of all species of sect. Inversiflora are more compressed and larger than those of species of sects Kinethrix, Lupulina and Alcistachys (with the exception of Bulbophyllum hamelinii W.Watson, which has larger but less compressed pseudobulbs). Phylogenetically, it forms a well-supported clade distinct from all the remaining sections of Madagascan Bulbophyllum (Gamisch et al. unpublished data). The combination of these properties uniquely identify this group of species; we therefore propose to place them in a section of their own.
During a recent field trip (2018), a first genus-level identification of a potential pollinator of Bulbophyllum in Madagascar was made (but see Gamisch et al. 2014 and references therein for respective reports from Réunion). Bulbophyllum cardiobulbum was observed (Gamisch, Sieder & Prehsler, pers. obs.) to attract several tiny (c 1.7 mm long) female flies (Fig. 13) of a hitherto unknown species of the genus Arcuator Sabrosky of the family Chloropidae (Dr. Michael von Tschirnhaus/Bielefeld University pers. comm.) remarkable for the lack of a terminal spur ("Endsporn") on the hind legs ("Hintertibia"), usually a diagnostic character of the genus Arcuator (Dr Michael von Tschirnhaus/Bielefeld University pers. comm.).
Pedicel and ovary ovoid-conical, slightly grooved, 1.1 -2 × 1.   Fitovinany (Fianarantsoa) regions. The species is found in the Andasibe-Mantadia, Maromizaha, Marojejy and Ranomafana protected areas. However, it is threatened by habitat destruction due to mining activities, selective logging, wood collecting for smallscale subsistence and tavy (slash-and-burn agriculture). With nine threat locations defined, the area of occupancy AOO likely less than 2,000 km 2 , the extent of occurrence EOO estimated to be less than 20,000 km 2 and a continuing decline on the EOO, AOO and the habitat quality, Bulbophyllum aubrevillei is therefore assessed as Vulnerable (VU) under criteria B1ab(i,ii,iii)+ B2ab(i,ii,iii). PHENOLOGY. September to January.   NOTES. Bulbophyllum aubrevillei is readily recognised by its long and slender bifoliate pseudobulbs, its thin arching inflorescence, and flowers with free ovate sepals, a recurved lip with a hollowed epichile, a column with subulate stelidia and an anther with a distinct conical lobe. It belongs in sect. Elasmatopus of the genus because of its slender pseudobulbs and leaves, slightly thickened rachis, free sepals, long acicular stelidia and appendiculate anther. It is closest to B. amphorimorphum which has similar flowers but unifoliate pseudobulbs. It differs from B. fierenanaense, described above, by the shorter pseudobulbs, leaves and inflorescence, smaller flowers with sepals that are shorter and acute vs lanceolate-attenuate and the ovate lip (vs longly lingulate). The species are compared in Table 2. Bulbophyllum aubrevillei, described and illustrated by Jean Bosser in 1965 from the Moramanga area in E Madagascar was compared with B. amphorimorphum H.Perrier which consistently has unifoliate pseudobulbs (vs bifoliate). Bosser differentiated the new species from the others in sect. Elasmatopus in his key because of its 4 mm long lip with the anterior part very concave and with raised margins. Six years later he described B. kieneri, based on a plant collected in the 'Tamatave' area by Kiener and cultivated at the Tzimbazaza Botanic Garden in Antananarivo. The single herbarium specimen in P comprises a small pseudobulb, a leaf and a few flowers; there also is a small anonymous drawing of the new species. Bosser wrote that it has the same morphology as the other species in sect. Elasmatopus but differed by its cylindrical canaliculate pseudobulbs with a short inflorescence at the base. There is no doubt that B. kieneri is the same as B. aubrevillei: the shape of the pseudobulbs is variable in B. aubrevillei and ranges from longconical to cylindrical, the longitudinal grooves are not uncommon in desiccated or old pseudobulbs, while the length of the inflorescence is also very variable with those in immature plants being shorter. When comparing the floral detail, helped by the excellent drawing by Jaap Vermeulen of the type specimen (P), it is evident that all segments, including the hollowed lip and column structure are identical to those of B. aubrevillei but at the lower end of its size range. It is interesting to note that Bosser, in his description of B. aubrevillei gave the floral measurements almost a quarter larger than the actual size of those of the type. In his description Bosser had the sepal colour as whitish spotted red and the lip whitish: field observations and photographic records have shown that the colour of B. aubrevillei is very variable ranging from very pale and scarcely spotted with red to almost completely purple-red with various grades in-between. It is clear that B. kieneri is a small, poor and / or immature plant of B. aubrevillei.
Large erect epiphytic plant 9 -18 cm tall, with a short woody cylindrical rhizome covered in brownish papery bracts, roots filiform, c. 2 mm in diam. Pseudobulbs ovoid to conical, more or less angular-tetragonal, 1.3 -4.3 × 1 -1.5 cm, yellowish-green, olive green or reddish-orange, with 2 apical leaves. Leaves erect to divergent, ligulate to narrowly lanceolate, 5 -10 × 0.7 -1.5 cm, contracted at the base into a 10 -15 mm petiole, tip slightly emarginate, pale green to olivegreen. Inflorescence erect, up to 20 cm long, 3 -5 mm in diam., with 10 -20 flowers. Peduncle about 2 = 3 the length of the inflorescence, 8 -12 mm long, with 3 -5 tubular peduncle sheaths at each internode. Rachis densely racemose, the flowers 3 -7 mm apart. Floral bracts oval, 6.5 -8 × 3 mm, obtuse to almost truncate, glandular on the exterior, reddish-brown towards the base. Flowers facing upwards with the lip erect and uppermost, 1.4 -1.6 × 1.2 -1.4 cm, greenish-yellow with the sepals more or less splashed with reddishbrown and darkly verrucose, the lip yellow with the disk green, randomly spotted red, the marginal hairs brownish-yellow to white. Pedicel and ovary terete, 4 -6.2 × 1. . It is most similar to B. jeanbosseri, described below, which was considered a variety by Bosser (2000: 169) but there are significant differences: in B. cylindrocarpum the pseudobulbs are distinctly angular (vs grooved), the plant and inflorescence are generally shorter, the floral bract is oval, obtuse to almost truncate (vs lanceolate and attenuate), the sepals, petals and lip are smaller by a third, the lip is oblong (vs oblanceolate) with the median ridge on the blade rounded (vs oblong) the stelidia are linear-dentate (vs falcate) and the anther has a smaller lobule.
The species was first listed by Frappier in 1880 but was not described until 1895 in Cordemoy's Flore de la Réunion, based on Frappier's manuscripts. He added two varieties, var. aurantiacum and var. olivaceum, based on the colour of the pseudobulbs but did not add further detail. In his review of sect. Kainochilus, Bosser (2000) selected a neotype for the species since none of the Cordemoy specimens from MARS corresponded with the description with any certainty. There are three damaged specimens possibly corresponding to this species remaining in the Cordemoy herbarium (MARS). In the same paper Bosser also described var. andringitrense from Madagascar. Robust erect epiphytic plant, 15 -20 cm tall, with a short ascending rhizome 5 -20 mm long, 4 -7 mm in diam., covered in brownish papery bracts; roots filiform, 1 -2 mm in diam. Pseudobulbs conical, longitudinally deeply grooved, 3.5 -5 × 1.5 -2 cm, rounded at the apex, yellowish-green, olive green or reddish-orange, with 2 apical leaves. Leaves erect-spreading, ligulate to narrowly oblong, 8 -15 × 1 -1.5 cm, contracted at the base into a 15 -23 mm petiole, tip slightly emarginate, pale green to olive-green. Inflorescence erect, rigid, 14 -28 cm long, 4 -7 mm in diam., with up to 30 flowers. Peduncle ½ to 2 = 3 the length of the inflorescence, with 2 -4 tubular peduncle sheaths, 7 -14 mm long. Rachis thickened, sub-densely racemose, the flowers 6 -12 mm apart, hollowed-angular beneath each flower. RECOGNITION. This is a large plant with erect coriaceous leaves, flowers with tiny petals, a hinged lip with distinct hairs around the margin and basal lobes and well developed stelidia that clearly belongs in sect. Kainochilus which has been confirmed by molecular phylogenetic data (Gamisch et al. unpublished data). It is distinct by the deeply grooved conical pseudobulbs, long erect spreading leaves, erect inflorescence with up to 30 flowers, the thickened rachis hollowed beneath each flower, the lanceolate attenuate floral bracts, non-resupinate flowers with the lip uppermost, an oblanceolate lip with a rounded oblong cushion on the blade, distinct bearded fasciculate hairs around the margins, the prominent falcate stelidia with angular wings beneath and an anther with a prominent lobule. It is interesting to note that the shape of the petals is variable, ranging from triangular to tridentate, even differing between the left and right-hand of the same flower.    (Gamisch et al. unpublished data). Consequently, B. cylindrocarpum is more derived than the more basal new species, and probably diverged following ancestral colonisation of Réunion via long distance dispersal from Madagascar.

Bulbophyllum jeanbosseri
Bulbophyllum cylindrocarpum was described by Frappier in Cordemoy in 1895, a fairly common species in the central forests of Réunion. In his revision of the sect. Kainochilus, Bosser treated a similar plant from Andringitra in Madagascar as the new var. andringitrense (Bosser 2000: 169) based on his own collection (Bosser 18510). Although not mentioned in his protologue, he marked one specimen (P00107328) as 'type' and another (P00107327) as an 'isotype' but following McNeill (2014: 1112) a lectotype had to be chosen: sheet P00107328 is most representative and is designated here as the Lectotype and sheet P00107327 as the isolectotype of the variety. The main differences between the species and var. were considered to be the shape of the pseudobulbs, slightly bigger flowers and a different lip. Since then further collections have become available and, based on considerable morphological and genetic differences, the var. is now considered a species in its own right. As the name has no priority outside its rank and as B. andringitranum Schltr., based on Perrier 14389 (now B. nutans (Thouars) Thouars), has precedence anyway a new name had to be assigned.
RECOGNITION. Bulbophyllum pentastichum has somewhat compressed ovoid pseudobulbs, a thickened rachis, the many flowers inserted into dimples in the rachis, a thick recurved lip and acicular stelidia, it fits well into sect. Calamaria. Molecular phylogenetic evidence confirms this (Fischer et al. 2007b;Gamisch et al. 2015). It is recognised by its long inflorescence with a substantially thickened rachis c. 1 = 3 of its length, the thick, almost scale-like, ligulate to oblong floral bracts that are at least 1 = 3 longer than the flower and completely cover the flower buds, and many small flowers that do not open widely and have a lip with a densely fimbriate margin.
Amongst the morphologically similar species in the section, it shares the hairy lip and flower shape with Bulbophyllum bicoloratum Schltr. and B. occultum Thouars but in those species the rachis is considerably thinner and the floral bracts are longer, thinner, wider and dorsally keeled. It is somewhat similar in habit, floral bracts and the verrucose exterior of its flowers to B. cryptostachyum Schltr. of which currently no phylogenetic data is available but that species has a much thinner rachis, a peduncle only 1 = 3 of the inflorescence (vs over ½), slightly longer and narrower floral bracts and a lip without hairs. It has similar flowers to the phylogenetically distantly related B. elliotii Rolfe (Gamisch et al. 2015;Gamisch unpublished data) but in B. pentastichum the plant is only half the size with much shorter leaves, a pendent inflorescence at least ¼ the length with a thinner rachis, and floral bracts at least 1 = 3 shorter and not surpassing the flower. Phylogenetically, B. pentastichum is part of a wellsupported subclade of sect. Calamaria containing B. rubrum Jum. & H.Perrier and B. senghasii G.A.Fisch. & Sieder (Gamisch et al. 2015;Gamisch et al. unpublished data). Bulbophyllum rubrum has a similar plant habit but a much thinner rachis, the floral bracts are narrower and more acuminate, and the flowers are about 1 3 larger and the lip has fewer and shorter hairs. Bulbophyllum senghasii has pseudobulbs that are not compressed, a thickened but shorter rachis, and the margins of the lip are erose (vs fimbriate).
Pfitzer (1898) described this species very well, referring to a robust plant with subglabrous pseudobulbs, fleshy leaves, long inflorescence with a thickened five-angled fleshy rachis, long broad floral bracts, and flowers with falcate petals and a geniculate lip with fimbriate margins. He referred to a singleleaved plant (singulis) but this may be an error or his specimen may have been immature (as in Fischer et al. 826). This description was elaborated by Kraenzlin (1908), who believed that Pfitzer had never published his Bolbophyllaria pentasticha, while changing the spelling of the genus name from Bolbophyllaria to Bulbophyllaria, and it is clear that they refer to the same species. Nomenclaturally, B. pentastichum Pfitzer ex Kraenzl. must be regarded as an illegitimate name, and as both Schlechter and Rolfe based their combi-   Mocquerys who travelled in Madagascar (Dorr 1997: 336) but there is no evidence of a specific origin. A number of plants seem to have found their way into botanic gardens and other collections around Europe; there are records of it flowering at Kew (1904: 29) and in the collection of Jeremiah Colman (a specimen and a watercolour by Matilda Smith of his plant is at K). Rolfe (1915: 181) mentioned this Colman Bulbophyllum as remarkable 'with a long reddish spike having the flowers concealed under five rows of bracts (B. pentastichum, Rolfe)'. It is puzzling why he used Pfitzer's epithet but attached it to his own name. Perrier (1937: 85), in his paper on the Bulbophyllum of Madagascar, described B. matitanense from the eastern littoral forest but did not include B. pentastichum in his text and had B. quadrifarium (p. 116) listed as an incompletely known species. In his orchid flora of Madagascar he included B. pentastichum (1939: 412), B. matitanense and its subsp. rostratum without Latin diagnosis (p. 418) and B. quadrifarium (p. 423) as incompletely known and undescribed. Hermans et al. (2007) treated Bulbophyllum matitanese as a synonym of B. pentastichum, the subsp. rostratum was validated (p. 115) and it was noted that B. quadrifarium might be the same as B. pentastichum (p. 119). This species has an interesting reproductive strategy and appears to be self-compatible. Rolfe (1905: 244) noted that it appeared to be highly self-fertile. However it has been recently shown that outcrossing individuals are also found. The outcrossing and selfing plants differ slightly in gynostemium structure, namely in the presence and absence of a rostellum. In outcrossing individuals the rostellum acts as a barrier preventing the pollinia falling onto the stigma. No individuals exhibiting both outcrossing and selfing have been observed. Other gross morphological differences in vegetative or floral phenotype between outcrossing and selfing individuals have not been observed indicating that selfing morphs probably arose only recently.
his advice and help. We would like to thank the anonymous reviewers for their constructive suggestions and corrections, Judi Stone and Juliet Beentje for the detailed drawings. We are also very grateful to Solo 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. We extend special thanks to Michael von Tschirnhaus (Bielefeld University) for fly specimen identification and Annemarie Heiduck (Salzburg University) for preparing photographs of the latter. The work at the University of Salzburg was supported by the FWF (Austrian Science Fund) grant P20726 and P29371 to Hans Peter Comes and grants P17124 to Michael Kiehn, University of Vienna, P20906 to Gunter Fischer.
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