New nematodes of the families Drilonematidae, Ungellidae, and Mesidionematidae from New Zealand megascolecid earthworms

Abstract

Abstract Iponema australe sp. n. and Siconema neozealandicum sp. n. are described from New Zealand endemic earthworms. Both new species are aberrant species in their genera. I. australe (Drilonematidae) is characterised by the ornamented eggshells with polar surface differentiation, nerve ring around the intestine, and four cephalic sensillae. Characteristic features of S. neozealandicum (Ungellidae) are cephalic hooks with diverging tips and thick bases, the tuberculate surface of the eggshell, and the presence of a lumen in the ovary. Females of an undescribed genus show features in common with Drilonematidae, including unusually large suckers with fibrous underlying tissue; however, the absence of males in our material does not permit formal identification. Three new species of Nemanoke gen. n. are described from Octochaetus huttoni (Beddard, 1892). N. pharyngata sp. n. can be distinguished from the two other new species by the long oesophagus: 670–770 urn compared with 310–361 μm in Nemanoke stomicula...