Descriptions of a new genus and two new species of Caribbean deep-water jawfishes (Teleostei: Opistognathidae)

A new genus and species of deep-water jawfish, Anoptoplacus pygmaeus, n. gen. n. sp., is described on the basis of two specimens collected off Arrowsmith Bank, Yucatán, Mexico, trawled in 240‒267 m. Although only 20.5‒22.5 mm standard length, they exhibit sexual dichromatism, appear to be adults, and have a number of reductive characters generally characteristic of miniaturization in fishes. Other characters of this new species of jawfish include single rows of straight and slender teeth in both jaws, a caudal fin that is not lanceolate and with the middle 10 rays branched, 20‒23 body scale rows, and 2–4 infraorbitals which are plate-like and broadly open laterally. A second new species of jawfish, Opistognathus schrieri, n. sp. is described based on two specimens collected off Curaçao in about 152 m. This species shares a unique combination of characters with O. melachasme, known only from Arrowsmith Bank, and O. nothus, from off North Carolina and the Gulf of Mexico. Both color pattern and the distribution of cephalic pores in adults distinguish the new species. All Atlantic jawfishes that occur in depths greater than 150 m are discussed and compared.