Structure of the seismosensory system of Psettodes erumei (Psettodidae, Pleuronectiformes)

Abstract

The structure of the seismosensory system of Psettodes erumei was studied. General and specific features in comparison with the previously studied representatives of the suborder Pleuronectoidei were revealed. Similarity is manifested in the presence of four main head canals, coronal commissure, interrupted supratemporal commissure transformed into a supratemporal canal, and one trunk canal developed on both sides of the body. The seismosensory system of Psettodes erumei is characterized by several plesiomorphous characters: the presence of a sensory segment in lacrimale of the eyed side and supracleithrum, the absence of disruptions in all sensory canals, and a strong branching of cutaneous canaliculi. Specific features of P. erumei involve the presence of a large number of fontanels on angulo-articulare, connection on the eyed side of CIO sites in lacrimale and infraorbitale, and the underdevelopment of the bony vault of the sensory canal in praeoperculum.