Roughcheek Sculpin, Ruscarius creaseri
Roughcheek Sculpin, Ruscarius creaseri, Female. Fish caught from coastal waters off Palos Verde, California, December 2025. Length: 7.6 cm (3.0 inches). Catch, photograph and identification courtesy of Zachary Fratello, Redondo Beach, California.
Roughcheek Sculpin, Ruscarius creaseri, Female. Tidal pool fish observed in coastal waters off Palos Verde, California, December 2025. Identification and photograph courtesy of Zachary Fratello, Redondo Beach, California.
Roughcheek Sculpin, Ruscarius creaseri, Female. Tidal pool fish observed in coastal waters off Palos Verde, California, June 2025. Identification and photograph courtesy of Vince Golder, Santa Cruz, California.
Roughcheek Sculpin, Ruscarius creaseri, Male. Fish collected from a tidal pool from coastal waters off Palos Verde, California, June 2025. Length: 5.8 cm (2.3 inches). Catch and identification courtesy of Zachary Fratello, Redondo Beach, California.
Roughcheek Sculpin, Ruscarius creaseri, Male. Fish collected from a tidal pool from coastal waters off Palos Verde, California, June 2025. Length: 7.8 cm (3.1 inches). Catch, photo and identification courtesy of Vince Golder, Santa Cruz, California.
Roughcheek Sculpin, Ruscarius creaseri, Male. Fish collected from a tidal pool from coastal waters off Palos Verde, California, April 2025. Length: 8.1 cm (3.2 inches). Catch, photograph and identification courtesy of Jacob Avelar, Ventura, California.
The Roughcheek Sculpin, Ruscarius creaseri, is a member of the Marine Sculpin or Psychrolutidae Family, that is in Mexico as charrasco cachetirugoso. Globally, there are only species in the Genus Ruscarius of which only this species is found in Mexican waters of the Pacific Ocean.
The Roughcheek Sculpin has an elongated tapering body with a large, depressed, flattened, and wide head with a pointed snout. They have a tan background and are covered with black-brown to red-brown with a striping pattern and five short square bars that extend to the lateral line anteriorly. They have a pair of large eyes on top of their head and a large broad mouth equipped with numerous small teeth set in bands on the jaws, vomer and palatine. They have blush throats and a dark bar that extends downward from behind the eyes. The dorsal fin has oblique bands composed of red spots on the rays and black spots on the membranes. The caudal fin and pectoral fins are spotted with red marks. They are sexually dimorphic with the females being lighter in color; the males have black anal and pelvic fins and the females pale fins. Their anal fin has 9 rays; their caudal fin is rounded; and their first dorsal fin has 10 spines, and their second dorsal fin has 11 to 13 rays and his high and rounded, their pectoral fins have 16 or 17 rays and extend to the 5th anal ray, and their pelvic fins have 1 spine and 3 rays and extend to the anus. The upper preoperculum spine is sharp, curved and points upward. They are covered with scales.
The Roughcheek Sculpin is a demersal species that is found in tidal pools and shallow rocky areas at depths up to 37 m (120 feet). They reach a maximum of 7.7 cm (3.0 inches) in length. They are lie-in-wait ambush predators that are herbivores that consume diatoms, small crustaceans, and mollusks. The Roughcheek Sculpin is poorly studied with very limited information available about their lifestyle and behavioral patterns including specific details on age, diet, growth, habitat, longevity, movement patterns, and reproduction.
The Roughcheek Sculpin is a straightforward identification due to the unique pattern on the anterior portion of the dorsal fin and the short square bars on the sides.
The Roughcheek Sculpin is a resident of Mexican waters of the Pacific Ocean but has a limited distribution being found from Cedros Island, Baja California, northward along the central and northwest coasts of Baja.
From a conservation perspective the Roughcheek Sculpin has not been formally evaluated. They are rare and secretive and being small in stature they are of limited interest to most.