Known only from a few records from south-western England and the western Mediterranean.
E. side of St Mary's, Scilly Isles, Cornwall, SW England. Sept 1984. 10m depth. 40mm long. PHOTOS: B.E. Picton.
Considered a rare species, it has only been found from south-western England and the western Mediterranean. Very little is known of its biology and natural history. The mantle dark brown and it is covered with small spiculate tubercles. Most are whitish, and these are arranged in reticulate pattern forming a network of white on a dark brown background. However there are other translucent brown tubercles scattered over the datk brown regions. There is also a 'zig-zag' narrow ridge down the dorsal midline. The gill and rhinophore pockest are raised. Reported to grow to at least 68mm long (Thompson & Brown, 1984)
• Thompson, T.E. & Brown, B.E. (1984) Biology of Opisthobranch Molluscs, Vol. 2: Ray Society: London.
Rudman, W.B., 2001 (November 4) Atagema gibba Pruvot-Fol, 1951. [In] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/factsheet/ataggibb