Thyasiroidea (Mollusca: Bivalvia) from the mud volcanoes of the Gulf of Cadiz (NE Atlantic) Author Rodrigues, Clara F. Author Oliver, Graham Author Cunha, Marina R. text Zootaxa 2008 1752 41 56 journal article 10.5281/zenodo.274249 b4d292b4-0c92-42c7-a47b-9a3577bd28be 1175-5326 274249 Axinulus croulinensis ( Jeffreys, 1847 ) (Fig. 28) Material examined . All from Gulf of Cadiz; twelve live-collected specimens, MSM01-03, stn 241 GKG12, Mercator mud volcano, 35º17.918'N , 06º38.717'W , 353 m , 6 May 2006 ( DBUA 00832.01); four live-collected specimens, MSM01-03, stn 242 GKG13, same locality, 35º17.870'N , 06º38.810'W , 350 m , 6 May 2006 ( DBUA 00832.02); one live-collected specimen, TTR15, stn AT576B, same locality, 35º 17.657N , 06º 39.129W , 428 m , 26 July 2005 ( DBUA 00833.01). Remarks. Axinulus croulinensis is recognised by the almost symmetrical oval outline and weak to absent posterior sulcus. It is widely distributed throughout the Atlantic Ocean. It has been recorded from 40 to 3800 m and has not been associated with any specific reducing environment ( Payne & Allen 1991 ). Dufour (2005) classified this as having Type 2 gills with single demibranchs and showing weak bacterial symbiosis.