Morphological description of the glochidia of Buldowskia suifunica (Bivalvia: Unionidae)

Freshwater mussels of the genus Buldowskia (Bivalvia, Unionidae) are distributed from the Amur River basin in Russia and China southward to the Korean Peninsula and some Japanese islands. This work is an integrative morphological study of Buldowskia suifunica glochidia from locations in the Primorsky Territory, the Russian Far East. Glochidia of B. suifunica, taken from the same gill have asynchronous development. The external and internal morphology of its shell has been characterized. The morphology of its sensory system, within three stages of larval development (immature, intermediate and mature glochidia), consists of hair cells as well as nonhair cells. Their muscle system is composed of massive adductor and minor muscle bundles. The FMRFamid-ergic nervous system turned out to be a complex system includes basal cells (neurons), their neurites and anterior neurons. FMRFamide and tubulin was found in all neurons. Glochidia of B. suifunica have only four 5-HT-lir neurons. We concluded that B. suifunica glochidial nervous system differs from those of the larval systems of planktotrophic marine mollusks.