Tylopsacas

Full name and orig. publication: Tylopsacas Leeuwenb., Taxon 9: 220 (28 Sept. 1960).

Etymology: From the Greek τύλος, tylos = pustule, and ψακάς, psacas = grain, alluding to the tuberculate seeds. 

Synonyms: Tylosperma Leeuwenb. (1958), nom. illeg., non Botsch. (1952).

Infrafamilial position: Gesnerioid Gesneriaceae (Gesnerioideae) - Beslerieae.

Description: Terrestrial herbs. Stem absent. Roots fibrous. Leaves rosulate, apparently alternate, petiolate, lamina oblanceolate, apex acute, base decurrent into the petiole. Cymes unilateral (cincinni), with numerous flower pairs, ebracteolate, shorter than the leaves. Pedicels slender. Sepals shortly connate at base, linear-lanceolate. Corolla white, tube slightly inflated in the middle, limb slightly bilabiate, with elliptic, rounded lobes. Stamens 4, didynamous, included; filaments inserted near corolla base; anthers reniform, coherent in pairs. Staminode present. Ovary superior, ovoid; stigma capitate. Nectary ring-shaped, with two enlarged dorsal lobes. Fruit a bi-(? to four-)valved capsule, valves thin and translucent. Seeds subglobose, somewhat flattened.

Chromosome number: Unknown.

Type and only species: Tylopsacas cuneata (Gleason) Leeuwenb.

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: In the Guayana Highlands.

Ecology: Terrestrial herbs, growing in montane forests of the Guayana Highlands.

Notes: The only species of the genus was originally described in Episcia; it seems to be rather isolated, possible relationships are with Cremosperma and Resia.

Selected references: Feuillet & Steyermark, in Fl. Venezuel. Guayana 5 (1999), reg. rev.

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

Illustrations:

Tylopsacas cuneata (Gleason) Leeuwenb., type and only species

Acta Bot. Neerl. 7, fig. 33 (1958)

 



last modified: 2007-07-13