A new species of parasitic copepod (Siphonostomatoida: Lernaeopodidae: Neoalbionella Özdikmen, 2008) infecting the skin of a gulper shark, Centrophorus sp. (Squaliformes: Centrophoridae), in the Gulf of Mexico, with a key to species of Neoalbionella

Abstract

AbstractWe describe male and female specimens of a species of NeoalbionellaÖzdikmen, 2008 (Siphonostomatoida, Lernaeopodidae), Neoalbionella dannytangisp. nov., infecting the skin of a gulper shark Centrophorus sp. (Centrophoridae) in the northern Gulf of Mexico. Females of the new species most closely resemble those of Neoalbionella globosa (Leigh-Sharpe, 1918) but are unique among congeners by having the combination of 1) terminal endopodal segment of antenna with a reduced distal tubercle having a minute protuberance, 2) maxillule with a spinulose lateral palp and praecoxal endite, 3) maxilla with a swollen tip nearly parallel with the distal surface of the bulla, and 4) maxilliped with a sub-circular spinulose pad along the proximal myxal margin of the corpus maxillipedis. The male copepod was attached to the tip of a female’s posterior process and was assigned to Neoalbionella by having a cephalosome nearly equal in length to the trunk and tapered caudal rami directed posteroventrally (swollen and directed anterodorsally in males of Lernaeopoda von Nordmann, 1832). It was distinct from those of all other congeners by having 1) an antenna terminal endopodal segment and maxillule similar to that of the female, 2) a maxilla syncoxa with an anteromedial process having seven large, conical denticles, 4) a bifid mediative process approximately as wide as the length of the shortest lobe, and 5) a caudal ramus with a unique configuration and number of setae. This is the second report of a species of Neoalbionella from the Gulf of Mexico and the third nominal species of Neoalbionella reported from gulper sharks (Centrophorus spp.). We also provide keys to females and males of Neoalbionella.