A study on the epidermal structure of Periophthalmodon and Periophthalmus mudskippers with reference to their terrestrial adaptation

• Published in: Ichthyological research Vol. 50; no. 4; pp. 310 - 317
• Main Authors: Zhang, J. (Nagasaki Univ. (Japan)), Taniguchi, T, Takita, T, Ali, A.B
• Format: Journal Article
• Language: English
• Published: Tokyo Springer Nature B.V 01-11-2003
• Subjects: ADAPTATION; BLOOD CIRCULATION; Boleophthalmus; BONY FISHES; Epidermis; Fish; INTERTIDAL ENVIRONMENT; Marine biology; Morphology; Periophthalmus; Respiration; Scartelaos; SKIN; Taxonomy
• ISSN: 1341-8998; 1616-3915
• DOI: 10.1007/s10228-003-0173-7

Epidermal structures of three species of Periophthaimus (Ps.) and two species of Periophthalmodon (Pn.) were investigated in relation to their lifestyle. All species of both genera lack a dermal bulge, which species of other two oxudercine genera, Boleophthalmus and Scartelaos, have in their epidermis. In Periophthaimus and Periophthalmodon species, which are highly terrestrial, the middle cells are well developed in the epidermis and the capillaries are distributed in the surface of the epidermis on the head and dorsal body. In Periophthaimus species and Pn. septemradiatus, the capillaries and blood vessels are also distributed in the epidermis of the abdomen, superficially in Ps. modestus and deeply in other species. In Ps. modestus, the capillaries are also densely distributed on the surface of the epidermis in the caudal area, whereas in other species, the epidermal capillaries and blood vessels of this area are located deep with a very low density. In Pn. schlosseri, the epidermal capillaries are not found in either the abdominal area or caudal area. A comparison of the distribution of epidermal capillaries among Boleophthalmus, Periophthalmodon, Periophthaimus, and Scartelaos species revealed that the skin makes a larger contribution to respiration in the species having a more terrestrial lifestyle. Goblet mucous cells are completely lacking in Periophthaimus species, whereas slimeiike materials were often found on the skin surface of Periophthaimus species. This finding suggests that Periophthaimus species have some unknown mechanism for producing mucus. In Pn. schlosseri, exposure of the dense capillary net on the surface of the head is likely to increase cutaneous respiration, but it also makes the fish an attractive target of bloodsucking insects.