Paraboea

Etymology: From the Greek μαρα, para = beside, alongside, close by, and Boea, alluding to the similarity and affinity with this genus.

Synonyms: Didymocarpus sect. Paraboea C.B.Clarke (1883), Roettlera sect., Paraboea (C.B.Clarke) Fritsch (1894), Boea sect. Caulescentes Fritsch (1894), Paraboea sect. Breviflores Ridl. (1905), Chlamydoboea Stapf (1913), Paraboea sect., Eu-Paraboea Ridl. (1923), Buxiphyllum W.T.Wang & C.Z.Gao (1981), Boea auct. mult. saltem p.p.

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

Description: Perennial, rosulate or caulescent herbs, often woody at the base, sometimes with straggling woody branches, occasionally monocarpic; usually woolly (at least young stems). Leaves opposite, or spiral in some rosulate species; upper surface usually thinly arachnoid, often glabrescent or with scabrous hairs beneath the wool; lower surface usually densely interwoven and usually branched, at least once near the base, more rarely the indumentum of spaced or clustered branched, stellate or dendroid hairs. Cymes axillary, pedunculate, few- to many-flowered, in some species (including the monocarpic ones) restricted to the upper part of the stem and combining to form a terminal thyrse. Sepals free almost to the base. Corolla obliquely campanulate or with short tube and flat limb, slightly bilabiate but the two lips concolorous, white, blue or violet. Stamens 2, arising in corolla tube; filaments usually thick, not bright yellow when exserted. Ovary ± cylindrical, stigma small, capitate, very rarely sublinguiform. Fruit a capsule, dehiscent along both sutures or only one, straight or spirally twisted, usually cylindrical or slightly flattened, occasionally short with a basal hump on the upper side.

Chromosome number: 2n = 18, 32, 34, 36.

Species number: Around 87.

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: Paraboea clarkei B.L.Burtt

Distribution: Throughout Malesia, from Sumatra to New Guinea and from S China to Borneo, including the Phillipines. 

Ecology: Usually growing on limestone (rarely quartzitic) rocks, in forest or sun-exposed places, 100-3200 m.

Notes: From the revision of Boea and its allies (Burtt 1984), Paraboea emerged in a very emended sense. Its main diagnostic character is the arachnoid, interwoven indumentum. Floral and especially fruit characters are rather diverse. Recognition of species alliances, leading to a subdivision (or eventually splitting) of the genus, has to be worked out yet.

Selected references: Burtt, Notes Roy. Bot. Gard. Edinburgh 41: 401-452 (1984), emend. & prov. rev.; Xu & Burtt, Edinburgh J. Bot. 48: 1-18 (1991), new spp.; Xu, Ann. Missouri Bot. Gard. 82: 570-580 (1995); Weitzman et al., Novon 7: 423-435 (1997); Wang et al. in Wu & Raven (eds.), Fl. China 18: 362-367 (1998) (Chinese spp.); Wong et al., Sandakania 13: 23-29 (1999), new sp.; Hilliard, in Grierson & Long, Fl. Bhutan 2(3): 1327 (2001), reg. rev.; Burtt, Thai Forest Bull. (Botany) 29: 81-109 (2001), annot. checklist (Thailand); Xu & Wei, Acta Phytotax. Sin., 42: 380-382 (2004), new. sp.

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