The morphology of the club glands on the dorsal fin of mature male shannies, Lipophvys pholis (L.) (Blenniidae: Teleostei)

The pelvic, pectoral, anal and dorsal fins of mature male, female and immature male Lipophrys pholis (L.) were examined by light microscopy for the presence of club glands. All fins except the dorsal showed a highly stratified epidermis and a thick cuticle. Club glands were present on the dorsal fin of mature male fisH but only during the breeding season. The development and decline of the club glands corresponds to the period of gonadal build-up and spawnout. Each club gland comprises several thousand bundles ofcolumnar cells. The columnar cells surround acentral pore which opens to the outside through a layer of Malpighian cells. The substance produced by the gland includes mucopolysacchdride. The function of the secretion is unknown and is discussed in relation to studies on similar glands in several Mediterranean blenniids.