Otolith and scale morphologies of doctor fish (Garra rufa) inhabiting Kangal Balıklı Çermik thermal spring (Sivas, Turkey)

Abstract

Garra rufa is one of the most popular therapeutic and commercially important fish in ichthyotherapy. Otolith and scale morphology provide new and useful information for fish identification and classification. Left-right asteriscus and lapillus otoliths from juvenile and adult doctor fish, and the scales from 6 different regions of the juvenile and adult fish body have been examined in Kangal Balıklı Çermik thermal spring (Sivas, Turkey). The otolith and scale morphological characters such as type, size, shape, mesial surface, lateral surface, antirostrum and rostrum shapes, focus position, circuli appearance, radii type and posterior and anterior margin shapes were distinguishable features for the juvenile and adult G. rufa samples. Three different otolith shapes were observed such as squared and discoidal otolith shapes for asteriscus pairs and oval to elliptic otolith shapes for lapillus pairs in the juvenile and adult doctor fish. Seven different scale shapes were described from six different body regions of the G. rufa in the current study. The graphical illustration of wavelets was used for both asteriscus and lapillus pairs of the fish to discover otolith variabilities. This is one of the first otolith and scale morphology studies for the juvenile and adult doctor fish. All these otolith and scale characters and their morphologies could be used for best alternative tools to identification, classification, phylogenetic relationships among the different freshwater and marine fish species, genera, populations or stocks.