Paramaka convexa (Spieth)

Paramaka convexa; Savage & Domínguez, 1992: 244; Blanco-Belmonte et al., 2003: 119; Sartori, 2005: 237.

Material. Venezuela, Edo Bolívar, Kamá river 5º25’11’’N – 61º13’05’’W, 1035 m , 24/XI/2005, 4 nymphs. Soroape river, 5º06’29’’N – 61º34’40’’W, 935 m , 25/XI/2005, 1 nymph. Idem, except date 21/ III /2006, 42 nymphs. Yuruani river, 5º05’32’’N – 61º05’47’’W, 880 m, 25/XI/2005, 3 nymphs. Small stream in the road to the Paují locality, 4º36’45’’N – 61º05’25’’W, 942 m , 17/ III /2006, 42 nymphs. Specimens were deposited at the MLBV (Venezuela) and IBN (Argentina).

Discussion. This species was known only from adults, until Blanco-Belmonte et al. (2003) described the nymph. According to them, gills were present on abdominal segments I–VI were platelike, biramous, with dorsal portion of gills III–VI frequently terminating in a small finger-like filament; gills on abdominal segment VII vestigial. The nymphs collected in the Guayana´s uplands also present the variation in the small finger-like filament of the gills. Some of the nymphs present the filaments, while other do not.

Distribution. Brazil, French Guiana, Surinam, Venezuela.

Ecology. Nymphs were mostly collected in large rocky open rivers (55–150 m wide) but also in a small rocky partially shaded stream (10 m wide). Collections corresponded to dry (March 2006) and rainy seasons (November 2005 and June 2007).