Cirroctopus glacialis (Robson, 1930)

Characteristics

1. Shell
   1. Shell V-shaped.
   2. Shell surface smooth.
   3. Basal shelf present.
   image info

   Figure. Dorsal and ventral views of a shell of C. glacialis stained with methylene blue. Photograph by R. Young.

2. Color
   1. The oral surface of the arms and web with distinctive appearance. "...circumoral ring of white patches, each of which lies astride an arm. Between this ring and the mouth, the web was bright reddish purple; peripherally and beyong the ring it was of an intense bluish purple. The pattern and coloration are extremely vivid..." (Robson, 1930).
   image info

   Figure. Oral view of G. glacialis showing pigmentation pattern. Photograph from Vecchione, et al., 1998.

Comments

C. glacialis differs from C. hochbergi in having a smooth rather than a rugose shell, a thick rather than a thin mantle septum, a peculiar pattern of pigmentation on the oral face of the arms and web and a caecum that is much larger than the stomach. Unfortunately, differences in fixation and physiological state could account for some or all of these apparent species characteristics.

Distribution

References

O’Shea, Steve. 1999. The Marine Fauna of New Zealand: Octopoda (Mollusca: Cephalopoda). NIWA Biodiversity Memoir 112: 280pp.

Robson, G. C. (1930). Cephalopoda, I. Octopoda. Discovery Report, 2:371-401.

Vecchione, M., U. Piatkowski and A. L. Allcock. 1998. Biology of the cirrate octopod Grimpoteuthis glacialis (Cephalopoda; Opisthoteuthidae) in the South Shetland Islands, Antarctica. S. Afr. J. Mar. Sci. 20: 421-428.