Material examined: BBB 2016: St. 26; St. 38. PD BB 2017: St. 16; St. 21; St. 43. GARCÍA 2015: St. 17bis (MACN-In: 43514, 43515, 43516, 43517).
Distribution: off Río de la Plata (Argentina) (37°17’S, 52°20’W, 183 m) (Wright & Studer 1889); off Malvinas Islands (50°32’S, 63°03’W150 m) (Pérez & Zamponi 2004); South Shetland Islands to Scotia Ridge between South Orkney Islands and South Sandwich Islands; abyssal plain west off Tierra del Fuego (150–5087 m) (Cairns 2006; Taylor et al. 2013); Terra Nova Bay, Antarctica (300 m) (Gavagnin et al. 2003); Burdwood bank (135 m) (present study).
Remarks: This species was previously cited under several synonyms at this area: Stenella acanthina Wright & Studer, 1889; Stenella (Dasystenella) acanthina Versluys 1906; Thouarella longispinosa Kükenthal, 1912; Thouarella (Euthouarella) longispinosa Kükenthal 1915; Thouarella acanthina: Kukenthal, 1915. Cairns (2006) pointed that more southerly specimens differ slightly in having somewhat smaller polyps and marginal spines that are longer (up to 2.4 mm), especially in relation to their basal width (H:W up to 3.5) and that are slightly curved inward toward the operculum. Given this wide variation and the limited differences between specimens of T. longispinosa and the description of D. acanthina, Taylor et al. (2013) proposed that T. longispinosa be synonymised with D. acanthina, noting that a revision of Dasystenella is required.