Ornithoboea

Etymology: From the Greek όρνις, όρνιθος, ornis, ornithos = bird, and Boea. It is obscure what the ‘bird’ alludes to (perhaps the rather short and conical fruits resembling a bird’s beak).

Synonyms: Lepadanthus Ridl. (1909), Brachiostemon Hand.-Mazz. (1934), Sinoboea Chun (1946).

Infrafamilial position: Didymocarpoid Gesneriaceae - "Advanced Asiatic and Malesian genera" (Weber 2004).

Description: Perennial herbs, stem curved at base. Leaves opposite, often (slightly) anisophyllous, petiolate, lamina ± ovate, obliquely subcordate at base, apex acute, margin crenate or serrate-dentate. Indumentum variable, in some species densely woolly or arachnoid. Cymes axillary, sometimes unilateral (pair-flowered cincinni). Sepals free to base, persistent, often reflexed. Corolla tube funnel-shaped or distinctly inflated in the upper part; limb bilabiate, the upper lip of two short blunt lobes, lower lip much larger, 3-lobed; palate with a beard of large unicellular club-shaped hairs; a line of hairs forming a circlet around the corolla mouth. Stamens 2 (the anterior pair); filaments straight or geniculate or with a definite sterile knob at the knee; anthers cohering face to face, reniform; staminodes 2-3. Ovary conical, pubescent or pilose. Fruit a spirally twisted capsule.

Chromosome number: 2n = 32.

Species number: 11.

Species names (incl. publication and synonyms): See Skog, L.E. & J.K. Boggan. 2005: World checklist of Gesneriaceae: http://persoon.si.edu/Gesneriaceae/Checklist.

Type species: Ornithoboea parishii C.B.Clarke

Distribution: From S China southwards to the northern part of the Malay Peninsula (China, Malaysia, E Myanmar, Thailand, Vietnam). 

Ecology: On rocks, in shaded, humid places; some (possibly all) species confined to limestone.

Notes: Some species, in particular O. arachnoidea (Diels) Craib (S China, N Thailand), are remarkable for the extraordinary similarity of the flowers with orchid flowers (floral mimicry? Burtt 1958a, Weber 1979).

Selected references: Burtt, Notes Roy. Bot. Gard. Edinburgh 22: 287-299 (1958), rev.; Weber, Gloxinian 29: 9-12 (1979), morph.; Wang et al. in Wu & Raven (eds.), Fl. China 18: 361-370 (1998) (Chinese spp.); Burtt, Thai Forest Bull. (Botany) 29: 81-109 (2001), annot. checklist, new spp. (Thailand).

Bibliography: See Skog, L.E. & J.K. Boggan. 2005. Bibliography of the Gesneriaceae. 2^nd edition: http://persoon.si.edu/Gesneriaceae/Bibliography.