Jumellea pachyceras Schltr., Repert. Spec. Nov. Regni Veg. Beih. 33: 299 (1925).
This species is very much like Jumellea hyalina. Differing by the height (10-30 cm), being taller, the leaves larger (3.5-9 cm x 6-9 mm ); the peduncle (10-13 mm), the bracts and pedicel (25 mm longer; the flowers larger (l6 mm long), with the parts heavier, the veins much less visible; the median sepal oblong obtuse and l6 mm long; the petals are of a very different form, oblong-elliptical. Sub obtuse and larger (15 x 4 mm) the labellum of the same form but twice as large (17-20 mm), more longly attenuate toward the base and without the callus basally, where there is a short costa; the spur (14 mm) is shorter than the labellum; finally the auricles of the rostellum in the form of an axe head, the upper angle obtuse. more projecting with the lower angle flattened.
Epiphyte in mossy forests, from 2000 m alt.; flowering in December-February.
As given for the genus, warm to cool growing epiphyte.
Species similar to Jumellea hyalina, but larger plant size, larger leaves, larger flowers, petal shape different, larger lip.
C. & SC. Madagascar
Flora of Madagascar Perrier 1939/81; Angraecoid Orchids Stewart, Hermans and Campbell 2007; Orchids of Madagascar Hermans 2007; Field Guide to the Orchids of Madagascar Cribb & Herman 2009; WCSP (2017). 'World Checklist of Selected Plant Families. 19.02-2017; http://apps.kew.org/wcsp/
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Botanical Drawing / Herbarium
Photograph copyright Swiss Orchid Foundation at the Herbarium Jany Renz Image used with kind permission.