Caraibops Prokofiev & Schwarzhans

Schwarzhans, Werner W. & Prokofiev, Artem M., 2017, Reappraisal of Synagrops Günther, 1887 with rehabilitation and revision of Parascombrops Alcock, 1889 including description of seven new species and two new genera (Perciformes: Acropomatidae), Zootaxa 4260 (1), pp. 1-74 : 13

Genus Caraibops Prokofiev & Schwarzhans , new genus

Type-species (monotypic): Synagrops trispinosus Mochizuki & Sano, 1984

Diagnosis. A genus diagnosed by the combination of 8 externally visible D1 spines and an anal-fin ray formula III + 9, and distinctive in the following combination of additional characters: pelvic-fin spine with regular sharp serrations along its outer margin from base to tip; no basioccipital fossa, no otophysic connection and no posterior openings of the myodome; three supraneurals, predorsal formula 0/0/0+2/; 9th D1 spine minute, only seen on radiographs; no vacant interneural gap below D1; distal element of last D1 pterygiophore enlarged; epaxialis attachment type 0; ectopterygoid toothless; cranial crests W-shaped but weak; inner edge of preopercle smooth (in adults) to finely denticulate or crenulate (in juveniles); otolith slender (OL:OH = 1.9–2.05) with pronounced postdorsal and low mid-dorsal region.

Discussion. Caraibops shares with Parascombrops the presence of a serrated pelvic-fin spine, considered to represent a synapomorphy for both genera. It differs in the absence of the vacant interneural gap below D1 (vs 8th interneural gap vacant), the predorsal formula (0/0/0+2/ vs /0+0/0+2/), both probably plesmiorphic character states, a higher number of branched rays in the anal fin (9 vs 6–7), the smooth inner rim of the preopercle in adult fish (vs always conspicuously serrated), a weakly developed cranial crests, the absence of denticles on the ectopterygoid and epaxialis attachment type 0 (vs 1); the polarity of the latter four characters being unresolved.

Caraibops and Parascombrops show a striking difference in epaxial muscle attachments to the dorsal-fin pterygiophores (0 and 1, respectively). Mooi & Gill (1995) indicated several cases of intrafamiliar variations in this character, i.e. within Plesiopidae (types 0 or 2), Sciaenidae (types 0 or 2), Cirrhitidae (types 1 or 2), and Labridae (types 0 or 2). Furthermore, the distribution of type 1 within the percoid and trachinoid families studied by Mooi & Gill (1995: Table 1), indicates that the independent origin of the type 1 in different taxa cannot be excluded. On the other hand, they also consider the possibility of a secondary loss of type 1 epaxial insertion. We find no grounds to resolve either variant in the case of Caraibops .

Etymology. From “caraib”, a collective name for the Indian tribes formerly inhabiting the Caribbean basin, combined with the ending -ops for the similar sounding to the related genus Parascombrops .

Species and distribution. A monotypic genus comprising C. trispinosus ( Mochizuki & Sano 1984) , known from the tropical Western Atlantic, in the Gulf of Mexico and the Caribbean southwards to Suriname at 36 to 550 m (mostly below 135 m) . Fossil otoliths are known from the Early Pliocene Cubagua Formation, Cerro Negro Member of the Araya Peninsula in Venezuela, figured as Parascombrops aff. argyreus (Gilbert & Cramer 1896) in Nolf (2013) .