Polynoidae (Annelida) from bathyal and abyssal depths in southern and eastern Australia

We provide a systematic account of the family Polynoidae (Annelida) from deep waters (> 1000 m) around Australia. Specimens were collected during surveys to the Great Australian Bight (2013–2017), east coast of Australia (2017), and southern seamounts off Tasmania (1997–2018). The taxonomic account includes 21 species from 12 genera, with accepted or provisional names, and we further describe nine new species. New species from four subfamilies described here include Arctonoinae: Parahololepidella mensa sp. nov.; Lepidastheniinae: Anotochaetonoe rubermaculata sp. nov.; Macellicephalinae: Bruunilla magnantennata sp. nov., Bruunilla posteroantennata sp. nov., and Polaruschakov investigatoris sp. nov.; Polynoinae: Eunoe albacauda sp. nov., Eunoe apicolata sp. nov., Eunoe benhami sp. nov., and Eunoe danmurrayi sp. nov. An additional 11 operational taxonomic units (OTUs) are represented by incomplete material. One species is given a new status: Eunoe abyssorum McIntosh, 1885 nomen dubium. One species previously placed in Bathyedithia Pettibone, 1976 is given a new combination as Polaruschakov retierei (Bonifácio & Menot, 2018) comb. nov. Two species formerly placed in Lagisca Malmgren, 1865 are new combinations as Harmothoe longipalpa Kirkegaard, 1995 comb. nov. and Harmothoe torbeni (Kirkegaard, 1995) comb. nov. Polyeunoa monroi Averincev, 1978 is recognised as a valid species distinct from Parapolyeunoa flynni (Benham, 1921), rather than a synonym of that species as previously suggested. We provide a phylogenetic analysis based on COI, 16S, 18S and 28S gene fragments placing our new taxa within the family Polynoidae. Molecular results support three monophyletic subfamilies Admetellinae, Macellicephalinae, and Polynoinae. This study provides the first comprehensive review of deep-water polynoids from Australia.