Dorylaimoidea From Some Subantarctic Islands

Abstract

Nine new species of Dorylaimoidea are described, collected by Mr. V. W. Spaull on ten subantarctic islands. Enchodelus signyensis is close to E. teres Thorne, 1939, but differs from it by shape of lip region, location of S2N, egg size, tail shape and shorter rectum. Eudorylaimus verrucosus is a large species, characterized chiefly by the verrucose egg shell; males have 13-14 supplements. E. isokaryon is also large; it has a very short tail and the two S1N are of equal size. Males have 13-17 supplements. E. spaulli, E. coniceps and E. pseudocarteri form a group of medium-sized species close to E. carteri (Bastian, 1865) and E. antarcticus (Steiner, 1916) in that the tail is conoidarcuate and the males possess a series of 6-13 spaced supplements beginning anterior to the spicules. All three have a shorter odontostyle than E. carteri and the lips less strongly offset than E. antarcticus. E. spaulli has a transverse vulva and a truncate lip region. E. coniceps has a transverse vulva, a narrow, high lip region, and longer spicules than the two other species. E. pseudocarteri has a longitudinal vulva and a truncate lip region. E. paradoxus is a large species, characterized by shape of lip region, odontostyle shorter than lip region width, finger-shaped tail and wrinkled advulvar cuticle; males have 22-27 supplements. This species resembles Rhyssocolpus, a genus whose validity is doubted. Mesodorylaimus signalus has a flag near the apex of the spicules; the vulva is longitudinal. M. imperator has spicules without flag, shorter than in M. signatus; the vulva is transverse and the odontostyle shorter; the advulvar cuticle is wrinkled. In both Mesodorylaimus species males are rare and non-functional. A list of sampling sites with species found is given.