Rhytidophyllum

Etymology: From the Greek ρυτις, ρυτιδος, rhytis, rhytidos = wrinkle; and φυλλον, phyllon = leaf; alluding to the wrinkled and blistered leaves. 

Synonyms: -

Infrafamilial position: Gesnerioid Gesneriaceae (Gesnerioideae) - Gesnerieae.

Description: Shrubs to trees, usually single-stemmed. Leaves alternate, mostly in a tuft on stem apex; petiolate, sometimes with stipule-like “auricules“ at the base; lamina lanceolate. Axillary cymes long-pedunculate, of several to many flowers in a double cincinnus or compound dichasium. Flowers rather short-tubed, obliquely campanulate, with wide mouth, limb spreading, greenish, brownish, with darker dots. Stamens 4, inserted distinctly (to 6 mm) above the corolla base. Ovary inferior. Fruit a dry, bivalved capsule.

Chromosome number: 2n = 28.

Species number: Ca. 20.

Type species: Rhytidophyllum tomentosum (L.) Mart.

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

Distribution: Caribbean region.

Notes: The genus is weakly distinct from Gesneria, the only differential character being apparently the higher insertion (more pronounced adnation) of the stamens to the corolla. Wiehler (1983), therefore, suggested to include the genus into Gesneria (but did not make formal transfers). He was, however, not followed by other workers. The flowers of Rhytidophyllum mostly exhibit a chiropterophilous pollination syndrome, but some species seem to be ornithophilous. 

Selected references: Skog, Smiths. Contr. Bot. 29: 1-182 (1976), rev. of Gesneria; Wiehler, Selbyana 6: 198-203 (1983). 

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