Histology and morphometry of the skin of the Korean ice goby Leucopsarion petersii (Gobiiformes, Gobiidae), in relation to its ecology and habitat.

The histological structure and morphometric characteristics of the skin of the Korean ice goby Leucopsarion petersii were investigated using light microscopy, two histological staining techniques, and SPSS statistical analysis. Skin samples from adult L. petersii fishes were collected from five body regions, including the head, operculum, dorsal body, lateral body, and ventral body. In all examined regions, the skin of L. petersii exhibited the general structure as in other teleost fishes, consisting of an epidermis and dermis separated by a distinct basement membrane with underlying skeletal muscle. The epidermis was composed of outermost flattened cells, basal cells, club cells, and mucous cells. However, some histological findings differed from the typical teleost fishes: I), the dermis was mainly characterized by a well-developed stratum compactum with an almost complete absence of the stratum laxum; II), Although epithelial thickness showed significant regional variation, it was positively correlated with basement membrane thickness (r = 0.417, p < 0.001; n = 100); III), Mucous cells, suggesting the formation of a protective mucosal barrier on the skin surface, were distributed in the outer epidermal layer; IV), club cells, implying retention of chemical defense mechanisms against environmental stress, were confirmed within the epidermis. Consequently, the skin histology of the skin of L. petersii may reflect adaptive responses to its thin body surface and to the fluctuating environmental conditions encountered in coastal and estuarine habitats.