Prostomium blunt, anteriorly truncate or rounded, anterior margin bifid, with anterior margin indented. Lateral horns absent. Caruncle present, continuing back to chaetiger 2 (posterior margin). Occipital antenna absent. Nuchal organ short, at most one segment long or long, extending back more than one segment. Eyes absent. Palps simple, lacking basal sheath. Dorsal ridge connecting bases of branchiae on chaetiger 1 absent. Prominent dorsal collar on setiger 2 absent. Dorsal branchiae present, first present on chaetiger 7 (reaching maximum size by chaetiger 8). Dorsal branchiae absent from many median and posterior chaetigers, last present on chaetiger 11–12. Dorsal branchiae continuous. Dorsal branchiae free and separate from notopodial lamellae throughout, all simple. First branchiae without process at base on anterior face. Accessory branchiae arising from posterior part of notopodium absent. Ventral branchiae absent. Chaetiger 3 without filament at base of branchiae. Dorsal crests absent. Ventral crests absent. Chaetiger 1 notopodium present. Chaetiger 1 notochaetae present (2–3 notochaetae only). Neuropodial lobe of chaetiger 2 rounded, approximately symmetrical. Neuropodial lobes of posterior chaetigers a single lobe. Interparapodial pouches absent. Chaetigers 2–4 similar, not strongly differentiated. Chaetiger 5 highly modified, enlarged and with specialised chaetae, with one type of modified spine present; simple, curved or subdistally inflated spines absent; spines with subdistal tooth or flange present; pennoned spines, with strongly asymmetrical tips absent; spines with flattened or cup-shaped tip absent; spines with terminal or subterminal bristles present; companion chaetae absent. Posterior modified notochaetae present. Notopodial hooded hooks absent. Neurochaetae of chaetiger 1 simple capillaries similar to those of subsequent chaetigers. Neuropodial hooded hooks present, first present on chaetiger 7. Neuropodial hooded hooks with accessory tooth or teeth above the main fang, 1 accessory tooth (bidentate), secondary tooth closely applied to the main fang, about 45º. Shaft of neuropodial hooded hooks of constant thickness, lacking a constriction. Neuropodial sabre chaetae absent. Neuropodial spines absent. Embedded bunches of notopodial needle chaetae absent. Pygidium small, cuff-shaped, with dorsal and ventral gaps.
Description generated from: Wilson, RS & McDiarmid, H 2013. Spionidae (Polychaeta)- A DELTA database of genera, and Australian species. Version 2; originally published as In RS Wilson, PA Hutchings & CJ Glasby (eds) Polychaetes: An Interactive Identification Guide. CSIRO Publishing, Melbourne.
Additional references:
Rainer, SF. 1973. Polydora and related genera (Polychaeta: Spionidae) from Otago waters. Journal the Royal Society of New Zealand 3, 545-564.
Read, GB. 1975. Systematics and biology of polydorid species (Polychaeta: Spionidae) from Wellington Harbour. Journal the Royal Society of New Zealand 5, 395-419.
Blake, JA and Kudenov, JD. 1978. The Spionidae (Polychaeta) from southeastern Australia and adjacent areas with a revision of the genera. Memoirs of the National Museum of Victoria 39, 171-280.