Laonice weddellia Hartman, 1978

Prostomium blunt, anteriorly truncate or rounded, anterior margin with entire anterior margin or bifid, with anterior margin indented. Lateral horns absent. Caruncle present, continuing back to chaetiger 1 (the end of setiger 1). Occipital antenna present. Nuchal organ long, extending back more than one segment, extending posteriorly to chaetiger 12–20. Eyes present; 4–6 eyes (4 in original description, 6 in Blake, 1983). 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 2. Dorsal branchiae continue to near posterior end of body or absent from many median and posterior chaetigers. 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 present; present on chaetigers , becoming more distinct in the posterior half of the body. Ventral crests absent. Chaetiger 1 notopodium present. Chaetiger 1 notochaetae present. Anterior setigers with 5 rows of chaetae. Neuropodial lobe of chaetiger 2 rounded, approximately symmetrical. Neuropodial lobes of posterior chaetigers a single lobe. Interparapodial pouches present. Interparapodial pouches on chaetigers 8–45 (first appear between 9 and 10, rarely 8 and 9; well developed through long region and absent from 25 or more possterior segments). Chaetigers 2–4 similar, not strongly differentiated. Chaetiger 5 unmodified, similar to subsequent chaetigers. Posterior modified notochaetae absent. Notopodial hooded hooks absent. Neurochaetae of chaetiger 1 simple capillaries similar to those of subsequent chaetigers. Neuropodial hooded hooks present, first present on chaetiger 20–21. Neuropodial hooded hooks with accessory tooth or teeth above the main fang, 1 accessory tooth (bidentate) or 2 accessory teeth (tridentate). Shaft of neuropodial hooded hooks of constant thickness, lacking a constriction. Neuropodial sabre chaetae present, in ventral-most positions, first on chaetiger(s) 12. Neuropodial spines absent. Embedded bunches of notopodial needle chaetae absent.

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:
Hartman, O. 1978. Polychaeta from the Weddell Sea quadrant Antarctica. Antarctic Research Series 26: 125-223;
Blake, J.A. 1983. Polychaetes of the family Spionidae from South America, Antarctica, and adjacent seas and islands. Antarctic Research Series 39: 205-287.