Full name and orig. publication: Henckelia Spreng., Arbeit. 2: 405 (20 April 1817).

Etymology: Named in honor of count Leo F. V. Henckel von Donnersmark (1785-1861) a German administrator and passionate amateur botanist. 

Synonyms: Roettlera Vahl (1804), nom. illeg., Loxocarpus R.Br. (1839), Codonoboea Ridl. (1923), Platyadenia B.L.Burtt (1971).

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

Description: Perennial herbs, lignescent subshrubs or woody shrubs. Stem erect, ascending or creeping. Leaves opposite or alternate, shortly to long petiolate, lamina form very variable, ranging from ribbon-like to suborbicular, often ovate or lanceolate, usually hairy. Inflorescences axillary, pedunculate, single-flowered or cymes of many flower pairs. Sepals 5, free to base or basally connate. Corolla variously shaped and colored, often infundibuliform, rarely campanulate or flat-faced. Stamens 2, usually included in the corolla, filaments long, often with an apical spur, anthers cohering. Nectary cylindrical, cup-shaped, sometimes lacking. Ovary usually slender conical or ovoid. Fruit usually a long plagiocarpic capsule, held horizontally and opening on the upper side. Seeds numerous, with various testa patterns.

Chromosome number: 2n = 18, 36.

Species number: C. 180, some undescribed.

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: Henckelia incana (Vahl) Spreng.

Distribution: From S India and Sri Lanka over Sumatra, S Thailand, the Malay Peninsula, Borneo, to the Philippines, Sulawesi and New Guinea. 

Ecology: In primary forests, often on sloping ground, river banks, or on damp rocks.

Notes:  The genus has been recently re-established for the inclusion of most of the Malesian species previously described under Didymocarpus (Weber & Burtt 1998d, Vitek & al. 2000). Salient differences exist in the fruit (plagiocarpic, dehiscence on the upper side only), the habit (continuous growth, no seasonal shoots), floral features and chromosome number (remarkable constancy of x = 9).

Five sections are recognized by Weber & Burtt (1998):

(1) sect. Henckelia (leaves alternate, rosulate, flowers small, ventricose, without nectary, fruits rather short; S India, Sri Lanka),

(2) sect. Didymanthus (C.B.Clarke) A.Weber & B.L.Burtt (leaves opposite, pair-flowered cymes, flower form variable, a cylindrical or cup-shaped nectary mostly present; W Malesia),

(3) sect. Heteroboea (Benth.) A.Weber & B.L.Burtt (leaves alternate, usually tufted on top of an unbranched stem, axillary inflorescences single-flowered, fruits long; from Sumatra to New Guinea),

(4) sect. Loxocarpus (R.Br.) A.Weber & B.L.Burtt (leaves alternate, rosulate, usually silver-hairy, pair-flowered cymes, corolla short-tubed to flat-faced, nectary absent, fruit short, usually with a basal hump; W Malesia),

(5) sect. Glossadenia A.Weber & B.L.Burtt (leaves alternate, distant or tufted; flowers in much condensed cymes, nectary unilateral, forming a ventral blade; W Malesia).

Selected references: Weber & Burtt, Beitr. Biol. Pflanzen 70: 293-363 (1998, "1997"), re-establ.; Vitek, Weber & Burtt, Ann. Naturhist. Mus. Wien 102 B: 477-530 (2000), list & nomencl. of 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. 2nd edition: http://persoon.si.edu/Gesneriaceae/Bibliography.


Henckelia sect. Henckelia
Henckelia incana (Vahl) Spreng., type of genus and section Henckelia

Wight, Icon. pl. Ind. or. 4, t. 1349 (1850), as Didymocarpus tomentosus

Henckelia innominata (B.L.Burtt) A.Weber & B.L.Burtt

S. India, Nilghiri Hills, phot. S. Vogel (1993)

Henckelia sect. Didymanthus
Henckelia hispida (Ridl.) A.Weber

Penins. Malaysia, Pahang, Cameron Highlands, phot. A. Weber (1979)

Henckelia hispida (Ridl.) A.Weber

Penins. Malaysia, Pahang, Cameron Highlands, phot. A. Weber (1987)

Henckelia malayana (Hook.f.) A.Weber

Penins. Malaysia, Pahang, Fraser's Hill, phot. A. Weber (1984)

Henckelia puncticulata (Ridl.) A.Weber

Penins. Malaysia, Johore, Kota Tinggi, phot. A. Weber (19..)

Henckelia puncticulata (Ridl.) A.Weber

Penins. Malaysia, Johore, Kota Tinggi, phot. A. Weber (19..)

Henckelia geitleri (A.Weber) A.Weber

Penins. Malaysia, Pahang, Sg. Pandan, phot. A. Weber (1987)

Henckelia sect. Heteroboea
Henckelia crinita (Jack) Spreng. (type of section)

Penins. Malaysia, Penang, phot. A. Weber (1986)

Henckelia quinquevulnera (Ridl.) A.Weber

Penins. Malaysia, Selangor, Templer Park, phot. A. Weber (1987)

Henckelia sect. Loxocarpus
Henckelia browneana  A.Weber (type of section)

Penins. Malaysia, Penang, phot. A. Weber (1979)

Henckelia caerulea (Ridl.) A.Weber

Penins. Malaysia,  G. Hijau, phot. A. Weber (1995)

Henckelia sect. Glossadenia
Henckelia flavobrunnea (Ridl.) A.Weber (type of section)

Penins. Malaysia, Pahang, Bkt. Teresek, phot. A. Weber (1979)

Henckelia pyroliflora (Ridl.) A.Weber

Penins. Malaysia, Pahang, Maran, phot. A. Weber (1986)


last modified: 2007-01-05