Anatomy and functional morphology of the feeding apparatus of the lesser electric ray, Narcine brasiliensis (Elasmobranchii: Batoidea).

摘要: Protrusion of the jaws during feeding is common in Batoidea (rays, skates, sawfishes, and guitarfishes), members which possess a highly modified jaw suspension. The lesser electric ray, Narcine brasiliensis, preys primarily on polychaete annelids using peculiar derived mechanism for protraction. ray captures its prey by protruding beneath substrate generating subambient buccal pressure to suck worms into mouth. Initiation this protrusion similar that proposed other batoids, swing distal ends hyomandibulae transmitted Meckel's cartilage. A "scissor-jack" model Narcine, coupling upper lower jaws, extremely flexible symphyses, allow medial compression entire complex. This results shortening distance between right left sides arch ventral extension jaws. Motion skeletal elements involved extreme convergent with described wobbegong shark, Orectolobus maculatus. also exhibits asymmetrical from midline processing, accomplished unequal depression hyomandibulae. Lower versatility functional motif batoid mechanism. pronounced kinesis N. brasiliensis partly function characteristics: euhyostylic suspension (decoupling hyoid arch) complex subdivided cranial musculature, affording fine motor control. However, would not be possible without loss basihyal narcinid rays. protrusible versatile maneuverable apparatus well-suited animal's benthic lifestyle.