Named by Carter.

Original description: Test spindle-shaped, large, in&64258;ated, usually with five or six post-abdominal chambers. Cephalis hemispherical; thorax, abdomen and first few abdominal chambers rapidly increasing in width, last few post-abdominal chambers strongly decreasing in width. Apical portion of test fairly pointed and covered with a layer of microgranular silica. Pore frames on early chambers relatively small, irregularly-shaped and arranged; on medial chambers pore frames mainly tetragonal and aligned in rows, some with costae-like ridges between. Pore frames on distalmost chamber(s) smaller and irregular.

Remarks: Canutus rennellensis n. sp. differs from the C. tipperi group in having finer, more irregular meshwork, and distal chambers are more constricted. It differs from C. baumgartneri Yeh in having much finer meshwork and pore frames on distal post-abdominal chambers are aligned rather than irregular.

Etymology: Species named for the type locality at Rennell Junction, the confluence of logging roads leading north to Masset and west to Rennell Sound; Graham Island, Queen Charlotte Islands.

Canutus rennellensis was named by Gorican et al. (2006). Its type specimen is GSC 111711 and is a 3D body fossil. Its type locality is Rennell Junction, Graham Island; GSC loc. C-080611, which is in a Pliensbachian marine shale in the Ghost Creek Formation of Canada.