Description of two new species ofOphthalmolycus(Teleostei: Zoarcidae) from the southern Ocean and key to species of the genus

Abstract

Two new species of zoarcid fish,Ophthalmolycus eastmanisp. nov., andOphthalmolycus polylepissp. nov. are described from specimens collected from the Bellingshausen Sea and Gerlache Strait, Southern Ocean, at depths of 1837 and 1056 m.Ophthalmolycus eastmanican be distinguished from its congeners by the following combination of characters: two posterior nasal pores; epidermal prickles on lips and snout; gill slit extending ventrally to the lower margin of the pectoral fin base; vertebrae asymmetrical 26 − 27 + 91 − 92 = 117 − 118; dorsal fin rays 111–113; dorsal fin origin associated with vertebra 6, with no free pterygiophores; pectoral fin rays 17–18; two postorbital pores; lateral line with ventral and mediolateral branches; scales extending anteriorly to just anterior to the anal fin origin; six branchiostegal rays; oral valve nearly reaching the anterior edge of vomer; palatine teeth in two rows anteriorly; 3–5 pseudobranch filaments; two well developed pyloric caeca; pelvic fin and vomerine teeth present.Ophthalmolycus polylepiscan be distinguished from its congeners by the following combination of characters: two posterior nasal pores; epidermal prickles on lips; gill slit extending ventrally just to below mid-pectoral fin base; interorbital pore present; two postorbital pores; lateral line triple with ventral, mediolateral and dorsolateral branches; scales extending anteriorly to predorsal area, abdomen, pelvic fins base, and pectoral fins base and axil; vertebrae asymmetrical 22 + 76; dorsal fin origin associated with vertebra 5; pectoral fin rays 18; six branchiostegal rays; oral valve overlapping the anterior edge of vomer; two rows of palatine teeth anteriorly; two vestigial pyloric caeca and 2 pseudobranch filaments; pelvic fin and vomerine teeth present. A key to the species ofOphthalmolycusis provided.