Morphology and function of the mandibular muscles in some coleoid cephalopods

Kear, Amanda J.. 1994 Morphology and function of the mandibular muscles in some coleoid cephalopods. Journal of the Marine Biological Association of the United Kingdom, 74 (4). 801-826.

Full text not available from this repository. (Request a copy)

Abstract/Summary

The functional morphology of the buccal mass of 23 species of cephalopod (Octopoda, 4 species; Teuthoidea, 17; Sepioidea, 2) was investigated by gross dissection, histology and observations on fresh preparations. Cephalopod beaks lack a joint or articulation point. The jaws slide and rotate around an area rather than a fixed point. During closing the superior mandibular muscle (SMM) provides the force of a bite and the largest movement vector, whilst the inferior mandibular muscle (IMM) acts to retract the upper beak, causing shearing action. Dorsal portions of the lateral mandibular muscles (LMM) flex the upper beak walls outwards, probably to accommodate the backwards sweep of the radula and buccal palps during closing. To open the beaks, the ventral portions of the lateral mandibular muscles pull the rear lateral walls of the two beaks towards each other, moving the lower beak back relative to the upper.

Item Type:	Publication - Article
Programmes:	BAS Programmes > Pre 2000 programme
NORA Subject Terms:	Biology and Microbiology
Date made live:	15 Mar 2017 14:20 +0 (UTC)
URI:	https://nora.nerc.ac.uk/id/eprint/516531

Item Type:

Publication - Article

Programmes:

BAS Programmes > Pre 2000 programme

NORA Subject Terms:

Biology and Microbiology

Date made live:

15 Mar 2017 14:20 +0 (UTC)

URI:

https://nora.nerc.ac.uk/id/eprint/516531