22. Thyasira debilis (Thiele, 1912) [Figs 10G–H]

Axinopsis debilis Thiele, 1912: 232, pl. 18, fig. 25

Material examined. • 62 spms, Stn. 3; • 7 spms, Stn. 7; • 9 spms, Stn. 8; • 1 spm, Stn. 10; • 3 spms, Stn. 14.

Type locality. Gauss station (Davis Sea) at a depth of 385 m.

Bathymetric distribution. 15–850 m.

Substrate. Soft bottom.

Geographical distribution. ANTARCTICA: Circum-Antarctic. SUBANTARCTICA: -. SCOTIA ARC: South Georgia, South Sandwich Islands, South Orkney Islands, South Shetland Islands. SOUTH AMERICA: Strait of Magellan, Falkland/Malvinas Islands.

Remarks. In contrast to the following species, it is significantly smaller (maximum shell height 2.3 mm) and the posterior end is angulated. Anterior and posterior ends are frequently incrusted with ferruginous material. We found it in depth between 35 and 100 m. The species is already known from the Maxwell and Admiralty Bays.

References. Dell (1964, 1990), Egorova (1982), Arnaud et al. (1986), Zelaya (2009), Engl (2012), Steger et al. (2023).