Otothyropsis, Ribeiro & Carvalho & Melo, 2005

Otothyropsis View in CoL View at ENA , new genus

Type species: Otothyropsis marapoama View in CoL by original designation.

Diagnosis. The clade that includes Otothyropsis , Otothyris and Pseudotothyris differs from the remaining genera of the Hypoptopomatinae by having an elongate posterior extension of the pterotic-supracleithrum which forms the dorsal margin of an enlarged lateral opening of the swimbladder capsule ( vs. quadrangular in shape and not extending posteriorly to form the dorsal margin of swimbladder capsule), and by having the supraoccipital forming the dorsal wall of the swimbladder capsule ( vs. supraoccipital does not contribute to dorsal wall of swimbladder capsule) (derived states of characters 8 and 12 of Schaefer, 1998). Otothyropsis , however, differs from Pseudotothyris and Otothyris by having enlarged odontodes on the dorsal and ventral margins of the snout ( vs. enlarged odontodes only on the dorsal margin); by lacking conspicuous crests of enlarged odontodes on the tip of supraoccipital and pterotic-supracleithrum in adults ( vs. adults with well-developed crests), and by having the abdomen completely plated in adults ( vs. adults with abdominal platelets reduced, sometimes restricted to lateral abdominal plate series).

The following characters were considered autapomorphic in our reanalysis of Schaefer’s (1998) phylogenetic framework of the Hypoptopomatinae , and phylogenetically diagnoses the new genus Otothyropsis : presence of a single median rostral plate; presence of enlarged odontodes in both dorsal and ventral snout margins (derived conditions of characters, 34 and 39 of Schaefer’s, 1998 phylogeny); and presence of the ocular diverticulum (reversal of character 42 of Schaefer’s, 1998 phylogeny). None of these characters, however, are exclusive to Otothyropsis , being considered homoplasies according to the parsimony analysis.

Etymology. The first part of the name is from Greek ( otos = ear and thyris = window) and is in reference to the Hypoptopomatinae genus Otothyris , to which the new taxon is closely related. The second part is from the Greek ( opsis = relating to sight and appearance); hence, resembling a hypoptopomatine fish. Gender: feminine.