Ten new species of siphonostomatoid copepods (Crustacea) associated with marine invertebrates from Korea

Abstract

Ten new species in three families (Asterocheridae, Dinopontiidae, and Entomolepididae) of siphonostomatoid copepods are described as associates of marine invertebrates from Korea. These new species are Acontiophorus decamerus n. sp., A. enneamerus n. sp., A. acuminatus n. sp., Asteropontoides parvus n. sp., Rhynchomyzon rostrale n. sp., Scottocheres jungi n. sp., and Thermocheres viridis n. sp. in the Asterocheridae, Stenopontius brevicauda n. sp. and S. alatus n. sp. in the Dinopontiidae, and Entomopsyllus aplanatus n. sp. in the Entomolepididae. The three new species of Acontiophorus differ from one another primarily in the segmentation of female antennule, the shape of genital double-somite, and the relative length of the caudal ramus. As diagnostic features of Asteropontoides parvus n. sp., the caudal ramus is 1.43 times longer than wide and the antennule is 19-segmented in the female. Rhynchomyzon rostrale n. sp. resembles R. rubrovittatum Sars, 1915, yet can be distinguished by its relatively shorter caudal ramus, which is about 2.8 times longer than wide in the female and by a larger seta on the basis of the maxilliped. In Scottocheres jungi n. sp., the female’s caudal ramus is 1.25 times longer than wide, with a 17-segmented antennule. Thermocheres viridis n. sp. distinctively possesses a small mandibular palp. In Stenopontius brevicauda n. sp., the female caudal ramus is slightly wider than it is long, with the inner coxal seta present on legs 2 to 4. Stenopontius alatus n. sp. uniquely features a wing-like lateral expansion on the genital double-somite and first abdominal somite. Entomopsyllus aplanatus n. sp. stands out among its congeners by having four spines and four setae on the third exopodal segment of both legs 1 and 4.