Studies Towards a Revision of the New Zealand Amphipodan Fauna

Abstract

A checklist of the New Zealand Amphipodan Fauna is given. It lists 214 species representing 32 families of Gammaridea, 2 of Cyamidea, and 13 of Hyperlidea. Sixty-two species of amphipods are fully described and figured. The New Zealand representatives of the Families Talitridae, Corophiidae and Amphithoidae of the S.O. Gammaridea are completely revised. Twenty-one of the species of Talitridae have been previously recorded from New Zealand; full descriptions of these have enabled a number of doubtful synonymies to be clarified. The species, Talitrus sylvaticus, Hvale media and Hyale maroubrae are new to New Zealand. The following new species are described: Orchestia sinbadensis, O. simularis, O. lesliensis, and O. rubroannulata; Talorchestia kapitiensis, T. kirki, T. chathamensis, T. Kaiapoiensis, and T. moerakiensis; Chiltonia enderbyensis and C. rivertonensis. The first five species are leafmould species, the last two are from fresh water. The genus Parorchestia is considered synonymous with Orchestia. A new species of Amphithoidae, Pleonexes lessoniae, is described and figured. Two species of Corophiidae have been previously recorded from New Zealand; the following species are new to New Zealand or have been recorded under other names: Corophium sextoni, C. acutum, C. acherusicum, and Ericthonius pugnax. Paracorophium lucasi is a new species. Corobphium sextoni is believed to have been introduced to England from New Zealand. Talitrus sylvaticus is believed to have been introduced to the Scilly Isles on New Zealand plants. The genera Hippomedon (Lysianassidae) and Phreatogammarus (Gammaridae) are revised, and the new species Hippomedon lachlani is described. Pontharpinia australis (Phoxocephalidae) is described and figured. On the generic separation according to type of mandibular palp suggested by Schellenberg (1938), it is considered that there are two species of Elasmopus recorded from New Zealand, Elasmopus neglectus and E. bollonsi, and five species of Maera, M.viridis, M. subcarinatus, M. inaecuipes, M. mastersii and M. carnlevi. Paracvamus boopis (Family Cyamidae, S.O. Cyamidea) is the only species of whale-louse definitely recorded from New Zealand. Fifteen species of Hyperides, representing all the material available in New Zealand, are described. Six of these, Cyllopus macropis, Hyperia spinigera, Parathemisto gracilipes, Hyperoche mediterranea, Paralycaea gracilis and Parascelus typhoides ? are new records for the New Zealand region. Fifty-eight species of Hyperiidea have been recorded from this region; keys are given to all families, genera and species represented. Cyllopus macropis is considered a valid species. Growth studies on Parathemisto gracilipes indicate that measurements of Parathemisto species are not of definitive value in separating the three species; but the species are here considered separate on morphological and ecological grounds. The term supralittoral is applied to those amphipods of the sea-shore which previous authors have called semi-terrestrial or terrestrial. The term terrestrial is then reserved for those species which are essentially independent of sea-water. The terrestrial amphipods are discussed with reference to their adaptations to terrestrial life. Certain adaptations are listed and other suggested, but it is concluded that the stable nature of the leafmould habitat removes the need for drastic adaptations. The marine amphipods show evidences of southern affinities Those taken in the Three Kings area by the Terra Nova Expedition are believed to be carried there by an upwelling of water from south of the 10° Convergence. The amphipods of Foveaux Strait and the inshore waters to the 100 fathom line are distinct from deeper water amphipods, and some species are of value as indicators of the different water masses.