California Clingfish, Gobiesox rhessodon
California Clingfish, Gobiesox rhessodon. Fish caught from a tidal pool in Malibu, California, January 2018. Length: 3.8 cm (1.5 inches). Catch, photograph, and identification courtesy of Ben Cantrell, San Diego, California.
California Clingfish, Gobiesox rhessodon. Fish caught from within the Ventura Harbor, Ventura, California, March 2021. Length: 4.1 cm (1.6 inches). Catch, photograph, and identification courtesy of Chris Moore, Peoria, Arizona.
The California Clingfish, Gobiesox rhessodon, is a member of the Clingfish or Gobiesocidae Family, and is known in Mexico as chupapiedras californiana. Globally, there are twenty-nine species in the genus Gobiesox, of which seven are found in Mexican waters, one in the Atlantic Ocean and five in the Pacific Ocean and one, this species, in both the Atlantic and Pacific Oceans.
The California Clingfish has an elongated “tadpole” like body that are tallest and widest at the pectoral fins. They are dark brown dorsally with a distinct cream-colored band across their eyes, a second wider cream-colored band between their pectoral fins, and a drab bar at the base of their golden caudal fin. They also have a spot on each side at the base of their dorsal fin. Their head is broader than the body but not as deep. They have an evenly rounded blunt snout, a mouth with thick lips that extends to the front margin of the eyes, 8 incisors on their mandible, and an irregular series of 7 to 9 upper conical teeth. They have 1 sharp spine on their gill cover. Their anal fin has no spines and 9 or 10 rays and their dorsal fin has no spines and 10 to 12 rays. The sucker on their ventral side is disproportionately large. Their skin is smooth. They do not have scales.
The California Clingfish is a shallow-water species found at depths up to 12 m (35 feet) in rocky areas within tidal pools exposed to high surf. They reach a maximum of 6.4 cm (2.5 inches) in length. They feed primarily on barnacles and small crustaceans. Reproduction is oviparous with eggs attached under rocks and guarded by adults and their larvae are planktonic. The California Clingfish is poorly studied with very limited information available about their lifestyle and behavioral patterns including specific details on age, growth, longevity, movement patterns, diet, habitat use, and reproduction.
The California Clingfish is a resident of Mexican waters of the Pacific but has a limited distribution being found from Magdalena Bay, Baja California Sur, northward along the central and northwest coasts of the Baja.
The California Clingfish is straightforward to identify due to its coloration and markings, thus cannot be confused with any other species.
From a conservation perspective the California Clingfish has not been formally evaluated but they should be considered to be of Least Concern with stable widely distributed populations. They are too small to be of interest to most.