Starksia spinipenis

Starksia spinipenis, the phallic blenny, is a species of labrisomid blenny native to the Pacific coast of Mexico from the Gulf of California to Acapulco. It prefers shallow sandy areas with weed growth. This species can reach a length of 5 cm TL. The specific name is a compound noun if spinis meaning "spine" and penis, a reference to the first spine in the anal fin of the males which is elongated and free of the fin membrane and is modified as a copulatory organ, a characteristic of the genus Starksia.