A new genus and four new species of onchidiid slugs from South-East Asia (Mollusca: Gastropoda: Pulmonata: Onchidiidae)

摘要

The taxonomy of the Onchidiidae has remained extremely confusing for decades. As part of an on-going systematic revision of the entire family, a new genus, Melayonchis Dayrat and Goulding gen. nov., and four new species (Melayonchis eloisae Dayrat sp.nov., Melayonchis siongkiati Dayrat and Goulding sp. nov., Melayonchis annae Dayrat sp. nov., and Melayonchis aileenae Dayrat and Goulding sp. nov.) are described. Species are delineated using an integrative approach, based on morphological characters and DNA sequences. First-hand field observations and pictures of live animals are provided in order to help future species identification. All four Melayonchis species live in mangrove forests. The geographic distribution of Melayonchis ranges from the Andaman Sea to the South China Sea through the Strait of Malacca. Records are based on entirely new collections from the Andaman Islands, Peninsular Malaysia, Singapore, Brunei Darussalam and Vietnam. The nomenclature of all existing onchidiid species-and genus-group names from that region is addressed, as well as intraspecific character variation within Melayonchis.