New Holothuria species from Australia (Echinodermata: Holothuroidea: Holothuriidae), with comments on the origin of deep and cool holothuriids

Abstract

Two aspidochirotid species, new to science, from the continental slope of southern Australia are described: Holothuria (Panningothuria) austrinabassa O’Loughlin sp. nov. and Holothuria (Halodeima) nigralutea O’Loughlin sp. nov. The fi rst represents the southernmost documented holothuriid, and is the sister species of the northernmost holothuriid species Holothuria (Panningothuria) forskali Delle Chiaje. The second is a very recent offshoot of the wide-ranging Indo- west Pacifi c Holothuria (Halodeima) edulis Lesson. Morphological and molecular genetic differences between these species pairs are detailed. Holothuria (Halodeima) signata Ludwig is raised out of synonymy with H. edulis.A lectotype for Holothuria (Halodeima) signata Ludwig is designated, The status of the subgenera Panningothuria Rowe and Halodeima Pearson is discussed. The occurrence of multiple madreporites in Halodeima is discussed