Geophagus abalios, G. dicrozoster and G. winemilleri (Perciformes: Cichlidae), three new species from Venezuela

Abstract

We describe three new species of Geophagus from the Orinoco and Casiquiare drainages of Venezuela, bringing the total number of described species in the genus to fourteen, and of Venezuelan species to six. All three species are distinguished from G. grammepareius, G. taeniopareius, G. argyrostictus and G. harreri by lacking an infraorbital stripe, which is either reduced to a preopercular mark or is absent. Geophagus abalios n. sp. reaches at least 163 mm SL; it is distinguished from G. dicrozoster n. sp., G. winemilleri n. sp., G. brachybranchus and G. proximus by lacking a preopercular mark. It can be further distinguished from the widely sympatric G. dicrozoster n. sp. by the squamation pattern, and upper jaw teeth arrangement. Preserved specimens of Geophagus abalios are distinguished from other Geophagus species without head markings except G. brokopondo by six vertical, parallel bars on the flank; it is distinguished from G. brokopondo by the anterior three bars, which are dorso-ventrally bisected by a clearer area, giving the impression of two thinner bars, whereas in the latter species all bars are solid; additionally, the sixth bar in G. abalios is elongate and restricted to the dorsal half of the caudal peduncle, above the lower lateral line, and in G. brokopondo the bar covers the entire caudal peduncle. Geophagus abalios is present in the llanos of the Orinoco drainage, reaching the Andean piedmont, the R o Caura in the Guyana Shield, and the higher Orinoco and Casiquiare drainages in Amazonas State. G. dicrozoster n. sp. and G. winemilleri n. sp. bear a preopercular mark, which distinguishes them from G. abalios n. sp., G. brokopondo, G. surinamensis, G. megasema, G. camopiensis, and G. altifrons, which lack head markings. G. dicrozoster n. sp. reaches at least 202 mm SL; preserved specimens are distinguished from other species with a preopercular mark by seven vertical, parallel lateral bars. The species is present in black water tributaries of the Orinoco in the Guyana Shield, and its middle and upper course, as well as in the Casiquiare and the headwaters of the R o Negro. G. winemilleri n. sp. reaches a maximum known size of 195 mm SL; preserved specimens are distinguished from other species with a preopercular mark by four broad, ventro-caudally inclined bars on the flank, plus a fainter bar on the dorsal portion of the caudal peduncle. G. winemilleri is described from the lower Casiquiaredrainage and the headwaters of the R o Negro in southern Venezuela, but may be distributed along the length of the R o Negro.