Mikhlina A.L.1, Vortsepneva E.V.2, Tzetlin A.B.1 2015. Functional morphology of the buccal complex of Flabellina verrucosa (Gastropoda: Opisthobranchia) // Invertebrate Zoology. Vol.12. No.2: 175–196 [in English].
2 White Sea Biological Station, Biological Faculty, Moscow State University, 119234 Moscow, Russia. E-mail: email@example.com
ABSTRACT: Buccal complex of Gastropoda is a complex structure consisting of the radula, odontophore and the buccal muscles. The general morphology and function of the buccal complex of Gastropoda was well-studied in several aspects. However, there are only a few integrated studies on both general and fine morphology, and the mechanism of feeding performed on opisthobranchs. Opisthobranchs’ feeding mechanisms are very specific and diverse, because opisthobranch molluscs have highly-specified feeding preferences. Unlike the majority of opisthobranchs, Flabellina verrucosa (Gastropoda: Opisthobranchia) has a wide range of feeding objects. The feeding mechanism of this species can be an example of the non-specified feeding mode. General and fine morphology of the buccal complex of F. verrucosa is studied in the present work. Based on three-dimensional reconstruction of the buccal complex and data on the fine morphology of muscles, we suggest the mechanism of the functioning of the food-obtaining apparatus. Prey is pulled into the buccal cavity due to blowing negative pressure and triturated using the radula. This feeding mechanism is suggested for Gastropoda for the first time and could be compared only with that in Tochuina tetraquetra and Dendronotus iris (Nudibranchia: Dendronotida), although the morphology of radula in these three species differs considerably.
KEY WORDS: radula, buccal muscles, histology, 3D-reconstruction, fine morphology, feeding mechanism.