Orchids of New Guinea

Species

Genus Trichotosia

Trichotosia Blume, Bijdr. (1825) 342. Type species: Trichotosia pauciflora Blume

Synonyms:

Genus Trichosia Blume, Tab. Pl. Jav. Orchid. (1825) t. 11 (sphalm.)
Eria subgen. Trichotosia (Blume) Blume, Mus. Bot. Lugd.-Bat. 2 (1856) 183.
Eria sect. Trichotosia (Blume) Rchb.f., Bonplandia 5 (1857) 54.

Sympodial epiphytes, occasionally terrestrial in open shrubby vegetation. Rhizomes very short (rarely with elongated rhizomes, not in New Guinea). Stem cane-like, clustered, usually much elongated, not fleshy. Leaves conduplicate, distichous, usually many (rarely few and then spirally arranged, not in New Guinea), deciduous, thin-leathery, articulate with the sheath; sheathing at the base, yellow or red-brown hairy at least on the leaf sheaths. Inflorescence lateral, opposite the leaf, a few- to several-flowered raceme. Flowers small to medium-size, resupinate, widely open or rather closed. Sepals free, usually hairy outside; mentum conical or spur-like. Petals free, almost always much narrower than the sepals. Lip 3-lobed, without spur, not mobile; callus hairy. Column with a column foot; anther terminal, incumbent; pollinia 8, solid; caudicles present; stipe absent; viscidium absent.

Distribution:

Nepal, Southeast Asia, Malaysia, Indonesia, the Philippines, Papua New Guinea, Pacific islands, east to Vanuatu. About 50 species; in New Guinea c. 25 species.

Habitat:

Epiphytes in lowland and montane forest, sometimes terrestrial in open shrubby vegetation.

References:

Blume, C. L. (1856). Cylindrolobus. Trichotosia. Museum Botanicum Lugdunum-Batavum 2, 182-5.
Brieger,F. G. (1981). Dendrobiinae. In Rudolf Schlechter, Die Orchideen, 3rd ed. (ed. F. C. Brieger,R. Maatsch & K. Senghas) pp. 636-752. Paul Parey, Berlin.
Comber, J. (1990). Orchids of Java. Bentham Moxon Trust, Royal Botanic Gardens, Kew.
Comber, J. (2001). Orchids of Suntatra. Royal Botanic Gardens, Kew.
Kranzlin, F. (1911). Erieae Benth & Hook.f. In Pflanzenr., Orchidaceae-Monandrae-Dendrobiinae (ed. A. Engler) 2, 1-176.
Ng, Y P. (2002). Plylogenetic relationships in tribe Podochileae (Orchidaceae: Epidendroideae) based on combined evidence from molecular and morphological data. Ph.D. thesis, University of London.
Pridgeon, A. M., P.J. Cribb, M.W. Chase & F.N. Rasmussen (Eds.). 2005. Genera Orchidacearum, Volume 4: Epidendroideae (Part one). Pp. 583-585. Oxford University Press, Oxford.
Seidenfaden, G. 1982. Orchid genera in Thailand. X. Trichotosia Bl. and Eria Lindl. Op. Bot. 62: 1-157.
Seidenfaden, G. and Wood, J.J. (1992). The orchids of peninsular Malaysia and Singapore. Olsen & Olsen, Fredensborg, Denmark.

Classification:

Family Orchidaceae
Subfamily Epidendroideae
Tribe Podochileae
Subtribe Eriinae
Genus Trichotosia

Notes:

Species of Trichotosia are slender-stemmed plants that are easily recognised by the more or less conspicuous covering of yellow or red-brown hairs on the leaf-sheaths and usually also on the leaves and the inflorescences. Some Dendrobium species may possess hairy leaf sheaths, but these hairs are blackish or white, never red-brown or yellow. Trichotosia is not often cultivated, although they are easy to grow.

Genus Trichotosia contains c. 85 species, in New Guinea 23 species:

Trichotosia atroferruginea
Trichotosia brachiata
Trichotosia brachybotrya
Trichotosia bracteata
Trichotosia breviflora
Trichotosia flexuosa
Trichotosia fractiflexa
Trichotosia gabriel-asemiana
Trichotosia gautierensis
Trichotosia gjellerupii
Trichotosia hapalostachys
Trichotosia hypophaea
Trichotosia iodantha
Trichotosia katherinae
Trichotosia microbambusa
Trichotosia molliflora
Trichotosia oreodoxa
Trichotosia paludosa
Trichotosia phaeotricha
Trichotosia rufa
Trichotosia subsessilis
Trichotosia thomsenii
Trichotosia xanthotricha