Cogniauxia Baill.
Cogniauxia Baill., Bull. Mens. Soc. Linn. Paris 1: 423. 1884.
Type: Cogniauxia podolaena Baill., C.V.A. Duparquet s.n. (P-00346202), Gabon, 1864.
Cogniauxella Baill., Bull. Mens. Soc. Linn. Paris 1: 424. 1884.

Perennial, herbaceous climber or trailer with several meters long shoots and dioecious sex system. The leaves are simple, petiolate, with ovate-cordate, entire or 3-5-lobed blade, to 18 cm long. The tendrils are bifid. The flowers are large, 7-8 cm across, showy. The male flowers are produced in racemes, the female flowers solitary. The receptacle-tube is elongated, dilated at the apex with five triangular sepals. The five yellow to orange petals are free, obovate, more or less asymmetric. The three (or rarely five) stamens 3 are inserted near the mouth of the tube on free filaments. Two anthers are bithecous, one monothecous with duplicate thecae containing tricolporate, irregularly reticulate, medium-sized pollen (polar axis c. 60 µm, equatorial axis 48-51 µm, (Khunwasi 1998)). The ovary is narrowly oblong with three placentae and many horizontal ovules. The style is short, fleshy with bilobed stigmata. The fruit is ovoid, 15 by 8 cm, shortly rostrate, fleshy and smooth, ripening red. The many seeds are compressed, to 2 cm long, with acuminate apex, almost bilobed base and a brown, smooth testa.

Two species along forest margins and roadsides, also in secondary forest in tropical Africa (Gabon, Cameroon, Congo, Angola).

Phylogenetically, Cogniauxia is sister to Telfairia and Ampelosicyos in the tribe Joliffieae (Schaefer & Renner 2011) from which it split about 35 million years ago (Schaefer et al. 2009).

Accepted species

Cogniauxia podolaena Baill., Bull. Mens. Soc. Linn. Paris 1: 424. 1884.
Cogniauxia trilobata Cogn., Études Fl. Congo 141. 1896.

Literature

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.

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