The Holognathidae (Crustaea : Isopoda : Valvifera) expanded and redefined on the basis of body-plan

Abstract

The Holognathidae are redefined on the basis of: semi-cylindrical body-plan, without laterally splayed coxal plates; parallel-sided and usually apically rounded pleotelson; and pereopod 4 much shorter than others, with spinose ischium-propodus. These features enable some species at least to have a tubicolous way of life. Four pleonites are defined laterally (and variously articulated or defined dorsally), the penes are separate, pleopods 1 and 2 have long apical setae, and maxillipedal palp articles 2 and 3 may be separated by a suture but never articulate.

The family now includes 21 species in four genera: Cleantioides Kensley & Kaufman (junior synonym Miratidotea Kensley), Cleantis Dana (junior synonym Zenobiana Stebbing), Holognathus Thomson, and Zenobianopsis Hale. A key to genera is presented and the species are listed, several in new combinations.

One of the two species of Holognathus, H. stewarti (Filhol) is the only valviferan with a mandibular palp, an attribute treated as an autapomorphy of the species.

Three new speices, Cleantioides albaniensis from southern Australia, C. striata from New South Wales, and Holognathus karamea from New Zealand, are described. Other Australian species are redescribed where necessary.