Feeding mechanisms in the barnacle Tetraclita squamosa (Bruguière)

• Published in: Journal of experimental marine biology and ecology 1991-01, Vol.154 (1), p.1-28
• Main Authors: Hunt, Marina J., Alexander, C.G.
• Format: Article
• Language: English
• Subjects: Barnacle; Biological and medical sciences; Cirripedia; Feeding; Fundamental and applied biological sciences. Psychology; Ingestion; Marine; Tetraclita; Tetraclita squamosa; Vertebrates: anatomy and physiology, studies on body, several organs or systems
• ISSN: 0022-0981; 1879-1697
• DOI: 10.1016/0022-0981(91)90074-7

T. squamosa is a suspension-feeding planktivore which augments its zooplankton diet with microplankton by microfiltration. The movements of mouthparts and maxillipeds were directly examined within the living animal by inserting an endoscope between the opercular plates. The mandibular palps function to remove particles trapped between themselves and the maxillae as well as enlarging the preoral cavity to accept food items. The maxillae can perform simultaneous and alternating movements which manipulate prey within the preoral cavity. The maxillules with their comblike setae pierce and tear the prey with simultaneous and alternating movements. Simultaneous and alternating contractions of the mandibles occur slightly later and complete the slicing and grinding mechanisms of food ingestion. The cirral activity of T. squamosa includes: testing, strong pumping beat, normal beat and extension. T. squamosa also displays opercular beak rotation through 360° following any period of cirral activity. In extension, the cirral fan can be held for up to 8 s and may rotate through 90° in relation to microcurrents. Microfiltration is achieved during pumping beat, strong pumping beat and normal beat, when currents induced by body movements allow microparticles to be trapped by the pappose setae of cirri I, which flank the oral cone.