Plesiolebias Costa

Plesiolebias Costa, 1989b: 193 (type species: Cynolebias xavantei Costa, Lacerda & Tanizaki, by original designation).

Diagnosis. Distinguished from all other genera of Plesiolebiasini by the following unique features: posterior process of quadrate and sympletic long (vs. short) (Costa, 1998a), interarcual cartilage absent (vs. present) (Costa, 1998a), rays of anterior portion of anal fin longer than posterior rays (vs. longer) (Costa, 1995a), and frontal squamation G-patterned (vs. F or D patterned) (Costa, 1998a).

Distribution. Southeastern Amazonian basin, including Xingu, Araguaia, and Tocantins river drainages, Brazil; and rio Paraguay basin, in northern Brazilian Pantanal (Fig. 13).

Remarks. The systematic accounts below should be viewed as a complement to the recent taxonomic revision of Plesiolebias (Costa, 1998c), where redescriptions of P. xavantei, P. l a c e rd a i, P. aruana, and P. glaucopterus are included.