Sicydium Schlechtend.
Sicydium Schlechtend., Linnaea 7: 388. 1832.
Type: Sicydium schiedeanum Schltdl., C.J.W. Schiede 51 (Holotype: B; Isotypes: LE, MO, P, W), Mexico, Veracruz, Hacienda de la Laguna.
Triceratia A. Rich. In Sagra, Hist. Phys. Cuba: 614. 1845.
Chalema Dieterle, Contr. Univ. Michigan Herb. 14: 71. 1980.

Perennial or annual climbers with herbaceous shoots, tuberous or fibrous roots and dioecious or rarely monoecious sex system. The leaves are simple, petiolate, the blade with (sub)cordate base and acuminate tip. The tendrils are simple or apically bifid. The flowers are small and produced in panicles. The receptacle-tube is saucer-shaped with five small sepals. The corolla is rotate with five ovate-lanceolate to triangular, whitish-green petals. The three or five stamens are inserted near the base of the tube on very short, free or fused filaments. The anthers are all monothecous or two anthers bithecous and one monothecous with straight thecae. The pollen is tricolporate, striate, and small (polar axis 17-37 µm, equatorial axis 17-29 µm, (Lira et al. 1998, Khunwasi 1998)). The ovary is ovoid with one pendent ovule and three linear styles ending in linear or punctiform stigmata. The fruits are baccate, globose, indehiscent, fleshy or fibrous, ripening black or a dry globose achene, c. 3 mm across. The seed is solitary, brownish, (sub)globose or compressed with rugose to verrucous testa.

The nine species grow in disturbed tropical and deciduous forest and along rivers, in dry forest and among shrubs of coastal lowlands in Central to tropical South America and the Caribbean and Mexico.

Sicydium is placed in tribe Triceratieae (Fevilleeae), where it groups with Pteropepon and the African Cyclantheropsis (Schaefer et al. 2009, Schaefer & Renner 2011).

Literature

Jeffrey C. and B. Trujillo. Cucurbitaceae In G. Morillo (ed.), Flora de Venezuela 5: 21. 1992.

Khunwasi, C. 1998. Palynology of the Cucurbitaceae. Doctoral Dissertation Naturwiss. Fak., University of Innsbruck.

Lira R. 1995. A new species of Sicydium Schlechtendal (Cucurbitaceae: Zanonioideae, Zanonieae, Sicydiinae) for the Flora Mesoamericana. Novon 5: 284-286.

Lira R., Alvarado J. L. and M. L. Ayala Nieto. 1998. Pollen morphology in Sicydium (Cucurbitaceae, Zanonioideae). Grana 37: 215-221.

Schaefer, H. and S.S. Renner. 2011. Phylogenetic relationships in the order Cucurbitales and a new classification of the gourd family (Cucurbitaceae). Taxon 60: 122-138.

Schaefer, H., Heibl, C., and S.S. Renner. 2009. Gourds afloat: a dated phylogeny reveals an Asian origin of the gourd family (Cucurbitaceae) and numerous oversea dispersal events. Proceedings of the Royal Society B 276: 843-851.