Full name and orig. publication: Tremacron Craib, Notes Roy. Bot. Gard. Edinburgh 10: 217 (1918).

Etymology: From the Greek τρεμα, trema = hole, pore, and ακρον, akron = extremity, tip, top; alluding to the anthers which open with a transversal slit at the top. 

Synonyms: -

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

Description: Perennial rosette herbs. Leaves radial, shortly petiolate, lamina elliptic, ovate, cordate-ovate or cordate-orbicular, crenate or dentate, both surfaces pubescent. Cymes long-pedunculate, with several flowers, bracteoles linear. Sepals free to base, narrowly lanceolate. Corolla yellow, white or red, subglabrous, tubular-campanulate, limb bilabiate, upper lip short, emarginate, lower lip with 3 rounded lobes. Stamens 4, of nearly equal length, rarely didynamous, exserted; filaments inserted near base of corolla tube; anthers globose, divaricate, locules apically confluent. Nectary annular or cyathiform. Ovary oblong or slender cylindrical; stigma bilobed. Capsule oblong or slender cylindrical.

Chromosome number: Unknown.

Species number: 7.

Type species: Tremacron forrestii Craib

Distribution: S China (Yunnan, Sichuan). 

Ecology: Growing in evergreen forests, on large boulders and on rocky cliffs, (1000-)2500-3200 m.

Selected references: Pan, Acta Phytotax. Sin. 26: 429-442 (1988); Wang et al. in Wu & Raven (eds.), Fl. China 18: 261-265 (1998) (Chinese spp.).

Bibliography: See Skog, L.E. & J.K. Boggan. 2005. Bibliography of the Gesneriaceae. 2nd edition:


Tremacron forrestii Craib, type species

Left: Ying T.S. et al., The endemic genera of seed plants in China, Fig. 128 (1993); with permission. 

Right: Li Z.Y. & Wang Y.Z., Plants of Gesneriaceae in China, Fig. 1.34 (2004); with permission.

Tremacron urceolatum K.Y. Pan

Li Z.Y. & Wang Y.Z., Plants of Gesneriaceae in China, Fig. 1.35 (2004); with permission.


last modified: 2007-07-13