Yellowfin Fringehead, Neoclinus stephensae
Yellowfin Fringehead, Neoclinus stephensae. Fish caught from coastal waters within Monterey Bay, Monterey, California, August 2021. Length: 10 cm (3.9 inches). Catch, photograph and identification courtesy of Luke Ovgard, Klamath Falls, Oregon.
The Yellowfin Fringehead, Neoclinus stephensae, is a member of the Tube Blenny or Chaenopsidae Family, and is known in Mexico as tubícola aletiamarilla. Globally, there are eleven species in the genus Neoclinus, of which three are found in Mexican waters of the Pacific Ocean.
The Yellowfin Fringehead has an elongated, slender, and moderately compressed body. They are scarlet, orange, brown to olive in color blue spots ventrally and striped fins. They have a large head with three pairs of multibranched large cirri over their eyes, a bluntly rounded snout, and a very large mouth that extends well past their eyes. They have prominent lips and numerous conical teeth. Their anal fin is elongated with the posterior third being deeper and has 2 spines and 34 or 38 rays; their caudal fin is square, their dorsal fin has 25 to 27 spines and 34 to 38 rays and has a very long base and extends from the middle of the head to the base of the tail; their pectoral fins have 14 to 16 rays and are large and fan-like; and their pelvic fins are small. They have 18 to 22 gill rakers. They are covered with minute scales.
The Yellowfin Fringehead is a demersal species that is found along rocky coastlines and bays near jetties at depths up to 27 m (90 feet). They reach a maximum of 10 cm (3.9 inches) in length. They live in various types of shelter, which they enter tail first with only their head exposed, that include abandoned shells and holes. They are known to have very poor eyesight and to exhibit fearless and extremely aggressive behavior, thus will attack anything large or small that approaches their burrows. They are ambush predators that feed primarily on crustaceans. In turn they are preyed upon by numerous Rockfishes and Sea Basses. Reproduction is oviparous with each female depositing up to 500 eggs. The eggs are sticky and attach the themselves to the substrate before being fertilized by the males. Both the females and the males guard the eggs until they hatch. The Yellowfin Fringehead 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 Yellowfin Fringehead is a resident of Mexican waters of the Pacific Ocean but has a limited distribution being from Guerrero Negro, Baja California northward along the central and northwest coasts of Baja.
The Yellowfin Fringehead is similar in appearance to the Onespot Fringehead, Neoclinus uninotatus and the Sarcastic Fringehead, Neoclinus blanchardi (both of which have ocelli spots on the dorsal fin).
From a conservation perspective the Yellowfin Fringehead is currently considered to be of Least Concern with stable, widely distributed samples. Due to their small stature, they are of limited interest to most.