Review of Brazilian jawfishes of the genus Opistognathus with descriptions of two new species (Teleostei, Opistognathidae)

• Published in: ZooKeys 2018-11, Vol.794 (794), p.95-133
• Main Authors: Smith-Vaniz, William F, Tornabene, Luke, Macieira, Raphael M
• Format: Article
• Language: English
• Subjects: Animalia; Atlantic Ocean; Chordata; Cytochrome-c oxidase; Esophagus; Faunistics & Distribution; Gene mapping; Genetic distance; Identification key; Identification keys; Molecular systematics; New species; Oceans; Opistognathidae; Opistognathus; Opistognathus maxillosus; Opistognathus whitehursti; Osteichthyes; Phylogenetics; Phylogeny; Physical characteristics; Pisces; Sibling species; Spines; Systematics; Taxonomy; Teeth; Zoology
• ISSN: 1313-2989; 1313-2970
• DOI: 10.3897/zookeys.794.26789

A new species of jawfish, , is described from the Vitória-Trindade Chain and Fernando de Noronha Archipelago off Brazil, a disjunct distribution of ca. 1,800 km. and its allopatric Caribbean sister-species, , both have a wide, fan-like upper margin of the subopercular flap and mostly over-lapping meristic data. The new species differs from in having the darkest spot on the spinous dorsal fin, when present, between spines 2-5, versus always present between spines 6-9, the buccal area surrounding the esophageal opening pale versus very dark and fewer oblique scale rows in longitudinal series (45-52 vs. 69-85). A second new species, , known from Brazil's mainland, has completely over-lapping meristic values with its allopatric Caribbean sister-species , but differs in lacking vomerine teeth and a supramaxilla and retaining the juvenile color pattern of the latter species in adults. Diagnoses, photographs, an identification key, and distributional maps are given for all Brazilian species of . Molecular phylogenetic analysis of partial cytochrome c oxidase subunit-I sequences indicates that specimens of the two allopatric pairs, - and - , form reciprocally monophyletic groups that differ from each other on average by 9 to 11%, with less than 1% average pair-wise genetic distance within-species. Similar patterns of phylogenetic structure were observed between reciprocally monophyletic (predominately allopatric) groups within nominal species of , suggesting the possibility of at least two additional undescribed species from the Brazilian Province.