A New Species of Orobdella (Hirudinida: Arhynchobdellida: Gastrostomobdellidae) from Tsushima Island, Japan

Abstract

A quadrannulate species of the genus Orobdella Oka, 1895 from Tsushima Island, Japan, Orobdella tsushimensis sp. nov., is described. It differs from other quadrannulate species of Orobdella in possessing the following combination of characters: color yellowish, III and IV uniannulate, male gonopore at XI b6, gastropore in XIII a1/a2, female gonopore in XIII a1/a2, 1/2+5 between gonopores, XXVI triannulate, gastroporal duct small and bottleshaped, epididymides in XVI to XIX, and atrial cornua coniform.