Ephemeroptera from the Venezuelan Guayanas´s Uplands: Families Leptophlebiidae, Euthyplociidae and Oligoneuriidae Author Domínguez, Eduardo Instituto de Biodiversidad Neotropical (IBN), CONICET-Universidad Nacional de Tucumán. Miguel Lillo 205. 4.000 Tucumán, Argentina. E-mail: mayfly @ unt. edu. ar Author Grillet, Maria-Eugenia Laboratorio de Biología de Vectores y Parásitos, Instituto de Zoología y Ecología Tropical, Facultad de Ciencias, Universidad Central de Venezuela, AP 47058, Caracas 1041 - A, Venezuela. E-mail: maria. grillet @ ciens. ucv. ve Author Nieto, Carolina Instituto de Biodiversidad Neotropical (IBN), CONICET-Universidad Nacional de Tucumán. Miguel Lillo 205. 4.000 Tucumán, Argentina. E-mail: mayfly @ unt. edu. ar Author Molineri, Carlos Instituto de Biodiversidad Neotropical (IBN), CONICET-Universidad Nacional de Tucumán. Miguel Lillo 205. 4.000 Tucumán, Argentina. E-mail: mayfly @ unt. edu. ar Author Guerrero, Edmundo Museo del Instituto de Zoología Agrícola Francisco Fernández Yépez, Facultad de Agronomia, Universidad Central de Venezuela, Maracay, AP 4579, Maracay, Venezuela. E-mail: edmundo. guerrero @ miza-ucv. org. ve text Zootaxa 2014 2014-07-04 3827 3 301 317 journal article 5314 10.11646/zootaxa.3827.3.1 54637182-8d50-4ef3-ad88-e3ee10f3d4cd 1175-5326 4920666 8C4821D8-072C-453A-ACF6-6EC539AE96AD Leentvaaria palpalis Demoulin Demoulin, 1966: 14 ; Domínguez et al ., 2001: 314 . Material. Venezuela , Edo Bolívar , Kamá river 5º 25’ 11’’N – 61º 13’ 05’’W , 1035 m , 20/ III /2006 , 1 nymph. Yuruaní river , 5º 05’ 32’’N – 61º 05’ 47’’W , 880 m , 25/XI/2005 , 1 nymph. Parupa river , 5º 40’ 49’’N – 61º 32’ 39’’W , 1281 m , 19/ III /2006 , 4 nymphs. Collectors : MEG , EG and AMO . Specimens were deposited at the MLBV ( Venezuela ) and IBN ( Argentina ). Discussion. This species was described only from nymphs, that are very unusual and easy to recognize for the very long labial palpi, which also present a basal prominence on segment I. Apparently, due to the scarce number of nymphs collected, this species is not very common in the region. This is the first time it is collected in Venezuela . Distribution. Surinam , Brazil , Venezuela (new country record) . Ecology . Nymphs were collected from the submerged substrates within the rivers during the rainy ( November 2005 ) and dry ( March 2006 ) seasons. Rivers were large water courses ( 30 m – 70 m wide), non-shaded, with bottom of rocks and gravels and acidic waters (pH=5).