|Morphologie de l'organe buccal ventral de Marphysa bellii (Audouin & Edwards) (Polychète, Eunicidae)|
Desière, M. (1967). Morphologie de l'organe buccal ventral de Marphysa bellii (Audouin & Edwards) (Polychète, Eunicidae). Ann. Soc. R. Zool. Bel. 97: 65-90
In: Annales de la Société Royale Zoologique de Belgique = Annalen van de Koninklijke Belgische Vereniging voor Dierkunde. Société Royale Zoologique de Belgique: Bruxelles. ISSN 0771-5528
Marphysa bellii (Audouin & Milne Edwards, 1833) [WoRMS]
The purpose of this article is chiefly devoted to the morphological study of the muscular and jaws systems of the ventral proboscis of the Eunicid Marphysa bellii (Audouin and Edwards). This buccal ventral organ extends back as a muscular sac underneath the oesophagus and is hollowed out into two cavities: dorsal and a ventral.On the floor of the dorsal cavity, lie the dorsal jaws and teeth while that on the ventral cavity contains a single pair of buccal ventral pieces (« mandibles of English authors »). These two-paired systems of maxillar are described thoroughly, in retracted or fully everted position. The movements of the teeth and jaws lying in the dorsal cavity are relatively independent from those of the buccal ventral pieces.The detailed study of the muscular system of the ventral proboscis reveals the existence of several layers of differently oriented muscles which either arise from the dorsal cavity or from the ventral cavity. These muscles, act as powerful retractors or protractors, or are directly responsible for the jaws systems.This completely distinct anatomy of the muscular and maxillar systems of the ventral and dorsal cavities gives rise to a modified interpretation of the buccal ventral proboscis of Eunicids which could be considered as being the resuit of two distinct and consecutive evaginations.This paper is illustrated by figures in which cavities, jaws systems and muscles of the buccal ventral proboscis of Marphysa bellii are spatially designed.