Monographs Details: Hypolytrum nudum C.B.Clarke
Authority: Maguire, Bassett. 1967. The botany of the Guayana Highland--Part VII. Mem. New York Bot. Gard. 17: 1-439.
Family:Cyperaceae
Description:Distribution and Ecology - Southeastern Venezuela and adjacent British Guiana, and Yaupes of Colombia. BRITISH GUIANA. Upper Mazaruni River, Kamakusa,H. Leng 396; Wusauta rapids, occasional, Maguire & Fanshawe 32644 without definite locality, Appun 599 (syntype of H. nudum K). VENEZUELA. Bolivar: Sierra Ichun, tributary of Rio Paragua, Rio Ichun, base of Sierra de Ichu, along river, Steyermark 90382 (US); Chimanta Massif, rainforest along Rio Apacara, Apacara-tepui, along stream bank, alt 400 m, Steyermark 74635; Caroni, Yuma-riba, Rio Ikabaru, alt 420 m, Cardona 2188 (US. YEN). COLOMBIA. Yaupes: Rio Apaporis, Jirijirimo, alt 250 M. H. Garcia-Barriga 13723 (COL, US) ; Rio Apaporis, Raudal Yayacopi and vicinity, quarzite base, alt SO ft, Schultes A Cabrera 15384 (US): Rio Apaporis. Raudal de Jirijirimo, below mouth of Rio Kananari, quarzite base, Schultes & Cabrera 14973 (K, NY, US).

Discussion:

Type. British Guiana. Upper Massaroonie, Appun 1696 (lectotype K, photo NY)

Hypolytrum nudum is at once discernible by the well developed spongy beak of the fructification (Fig. 16 K), which is actually the extension of utricles not filled by the contained achene. The species, hitherto recorded only from British Guiana, is apparently a new addition to the floras of Venezuela and Colombia. The recently determined collections mark a considerable range extension in southeastern Venezuela and Amazonian Colombia, but no collection was noted in between the two areas, i.e., northern Brazilian Amazonia.

Distribution:Guyana South America| Venezuela South America| Colombia South America|