OCCASIONAL PAPERS of the MUSEUM OF NATURAL HISTORY The University of Kansas Lawrence, Kansas NUMBER 31, PAGES 1-22 JULY 19, 1974 NEW SPECIES OF FROGS ( LEPTODACTYLIDAE : z< WkUTHERODACTYLVS ) FROM THE AMAZONIAN LOWLANDS OF ECUADOR AUG 1 2 1Q74 By HARVARJ)ohn D. Lynch 1 UNIVERSITY Herpetological exploration of tropical rainforest habitats at Lago Agrio and Santa Cecilia, Napo Province, Ecuador, has established the co-occurrence of sixteen species of the leptodactylid frog genus EleutherodactyJus. None of these species is known only from these two localities, and two do not occur at Santa Cecilia and another does not occur at Lago Agrio. Ecological studies in progress and nearing completion require that the unnamed species be described. At the onset of field work in 1966, nine of the sixteen were already named (E. acuminatus Shreve, E. altamazonicas Barbour and Dunn, E. conspicillatus Gunther, E. diadematus Jimenez de la Espada, E. lacrimosus Jimenez de la Espada, E. nigrovittatus Andersson, E. ockendeni Boulenger, E. pseudoacaminatus Shreve, and E. sulcatus Cope). Three species have been described since 1966 (E. croceoinguinis, E. orphnolaimus, and E. variabilis; Lynch, 1968a, 1970). Four species are currently unnamed. One is a species of the E. fitzingeri group and will be described elsewhere ( Lynch, MS ) . The other three are species of the E. unistrigatus group (roughly equivalent to Group II of Cochran and Goin, 1970). The E. unistrigatus group is defined as follows : heads of "normal" width ( head width 30-40% snout-vent length), skin of abdomen coarsely areolate, first finger shorter than second, all digits bearing discs on narrowly to broadly dilated pads, 1 Associate Professor of Zoology, School of Life Sciences, University of Nebraska, Lincoln, 68508; and Associate in Herpetology, Museum of Natural History, The University of Kansas.