Grimpoteuthis bathynectes Voss & Pearcy, 1990

Introduction

G. bathynectes is known from the 13 specimens reported in the type description. They were captured in bottom trawls during a study of the fauna of the continental slope and the Tufts and Cascadia Abyssal Plains.

Characteristics

1. Arms and web
   1. Arms subequal, with arms IV generally shortest.
   2. Web formula, variable, usually ABCDE.
   3. Web on dorsal arm margin extends nearly to arm tip.
   4. Web nodule present on ventral margin of each arm near, at or nearly at the termination of the web.
   

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   Figure. Oral view of left arm I of G. bathynectes, male, 50 mm ML. Drawing from O'Shea (1999).

2. Suckers
   1. Dorsal arms with 47-58 suckers.
   2. Sucker arrangement: first 4-5 suckers small or minute, followed abruptly by larger suckers that increase in size over first third of arm length, then gradually decrease to tip.
   3. Sexual dimorphism in suckers: Males - largest sucker diameter 4.3-6.7% of ML, shape globular; females - largest sucker diameter 2.6 -3.5% of ML, shape tubular.
   4. Cirri short: length 0.7 - 1.5 x largest sucker diameter.
   5. First cirri between suckers 3 and 4.
   

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   Figure. Arm suckers and cirri of G. bathynectes. Female, 58 mm ML; male, 42 mm ML. Drawings from O'Shea (1999).

3. Shell
   1. "...U-shaped, formed of rounded-edged flat strip that tapers to a thin flat point distally."
   2. "Fin insertions long and form slight angle near base with rounded apex."
   

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   Figure. Dorsal view of shell and lateral view of wing of G. bathynectes, male, 53 mm ML. Drawings from O'Shea (1999).

Comments

The above description is taken from Voss and Pearcy, 1990. More details of the description of G. bathynectes can be found here.

Among Pacific species, G. bathynectes differs from:

• G. abyssicola in having fewer suckers (58 vs 77; web nodule at sucker 26 vs 32-34), shorter cirri (1.5 vs 2.5 x largest sucker diam.), position of first cirri (3-4 vs 4-6), shell shape (lateral arm of shell not expanded vs lobelike), anterior salivary present vs absent.
• G. tuftsi in having sexual dimorphism in sucker shape, less elongate gills, shorter cirri, absence of enlarged suckers near web nodules and no radula (Voss and Pearcy, 1990).
• G. innominata in the lack of peculiar features of the shell and, possibly, a shorter gill (half-orange vs semi-sepioid).
• G. hippocrepium by no clear characters other than locality.
• G. meangensis by, apparently, the lack of large shoulder blades on the shell.
• G. pacifica in having more suckers (77 vs 52).

Distribution

G. bathynectes is known only from the Tufts and Cascadia Abyssal Plains in the North Pacific off Oregon. The type locality is 45°01.1'N, 135°12.0'W, 3932 m.

References

Voss, G. L. and W. G. Pearcy. 1990. Deep-water octopods (Mollusca: Cephalopoda) of the Northeastern Pacific. Proc. Calif. Acad. Sci. 47: 47-94.

Information on the Internet

• Video: Octopus Ballet. Interactive Ocean. University of Washington.