Four New Species of Doliocarpus (Dilleniaceae) from the Brazilian Amazonian Region

Abstract

Summary. Four new species of the genus Doliocarpus (Dilleniaceae) from the Amazonian region of Brazil are described and illustrated (D. aracaensis, D. aureobaccus, D. kubitzkii and D. pruskii) and the relationships with their allied species are discussed. D. pruskii is remarkable for its opposite leaves in an otherwise predominantly alternate-leaved family. Doliocarpus is a neotropical genus of about 45 species distributed throughout southern Mexico, Central America, the Antilles, the Guianas, Venezuela, Colombia, Ecuador, Peru, Bolivia, Brazil and Paraguay (Aymard & Miller 1994), with the greatest species diversity in Brazil. The genus can be distinguished from the other neotropical Dilleniaceae by the following features: mostly lianas, inflorescence ramiflorous, fasciculate or glomerate, gynoecium unicarpellate, 1-celled, fruit a berry, and seeds with white arils. Doliocarpus aracaensis Aymard sp. nov. a Doliocarpo paraensi Sleumer foliis ellipticis vel lanceolato-ellipticis margine integris sed sinuatis, supra secus costam nervosque trichomatibus erectis obductis, subtus secus costam nervosque sericeis, nervis lateralibus adscendenti-curvatis 1.5 - 2 mm a margine conjunctis, petiolo dense appresso-pubescente, pedunculo dense sericeo; sepalis inaequalibus (internis obovatis, externis ellipticis) extus dense sericeis; petalis 2.5 - 3 mm longis, obovatis; antheris c. 0.8 mm longis, bacca dense sericea 4- 5 mm diametro differt. Typus: Brazil, Amazonas. I L. do Amaral et al. 1688 (holotypus INPA!; isotypi NY., PORT!). Liana; branches densely sericeous, becoming glabrous when mature. Leaves coriaceous, elliptic or narrowly elliptic, 12 - 16 x 6 - 8 cm, base cuneate, apex acuminate, margins subrevolute, entire, sinuate mostly in the upper half, becoming glabrous on the upper surface except along the midrib and secondary nerves where covered by erect trichomes, glabrous on the lower surface except for the sericeous pubescent midrib and secondary nerves, lateral nerves 13 - 15, convergent and linking close to the margin, petioles 1.5 - 1.7 x c. 2 mm, exalate, covered with dense appressed pubescence. Inflorescence sessile, axillary, bracts obovate-elliptic, 2 - 3 mm long, densely appressed pubescent externally, glabrous internally. Sepals 5, 3 6 mm long, unequal (internal obovate, external elliptic) sericeous externally,