pedal retractor muscle
Quick Summary
The pedal retractor muscles in bivalve mollusks are internal muscles located behind the adductor muscles. Their primary function is to retract the foot, aiding in movements like burrowing and anchoring. In bivalves that attach themselves with a byssus (a strong fibrous thread), these muscles are reduced and function as byssal retractors, pulling the animal closer to the surface it's attached to. In some species, like oysters, these muscles are entirely lost due to the extreme reduction of the foot.12
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- bivalveLocomotion
…are the anterior and posterior pedal retractors. They retract the foot and effect back-and-forth movements. The foot is extended as blood is pumped into it, and it is prevented from overinflating by concentric rings of circular, oblique, and longitudinal muscle fibres, which also help to direct pedal extension and permit…
Read More…are the anterior and posterior pedal retractors. They retract the foot and effect back-and-forth movements. The foot is extended as blood is pumped into it, and it is prevented from overinflating by concentric rings of circular, oblique, and longitudinal muscle fibres, which also help to direct pedal extension and permit…
Read More - bivalveThe mantle and musculature
…are paired anterior and posterior pedal retractor muscles. Where the anterior adductor muscle is reduced, so are the anterior pedal retractors. In highly active burrowers, paired anterior pedal protractors and pedal elevator muscles occur—for example, the family Trigonioidea.
Read More…are paired anterior and posterior pedal retractor muscles. Where the anterior adductor muscle is reduced, so are the anterior pedal retractors. In highly active burrowers, paired anterior pedal protractors and pedal elevator muscles occur—for example, the family Trigonioidea.
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