About Diademichthys lineatus (Sauvage, 1883)
Diademichthys lineatus, commonly known as the long-snout clingfish, is a small fish species that reaches a maximum length of 5 centimetres (2.0 in). It has an elongated body and an elongated, spatulate snout. Snout shape can be used to identify the fish's sex, as females have longer and more slender snouts than males. This sexual dimorphism corresponds to different diets between the two sexes. The base body color of the species ranges from dark brown to red-brown, with three yellowish longitudinal lines running along the body: one along the top of the body, and two along the median axis of each flank. There is a yellow spot at the center of the caudal fin, and yellow coloration may also be present on the snout. Long-snout clingfish have been recorded producing a grammistin-like toxic mucus on their skin. This species is widespread across tropical waters of the Indo-West Pacific, ranging from the Gulf of Oman to Papua New Guinea. It inhabits reef environments, and is most often found associated with long-spined sea urchins, especially those in the genus Diadema.
