Snubnose Sculpin, Orthonopias triacis

Snubnose Sculpin, Orthonopias triacis. Fish caught from within Monterey Bay, Monterey, California, August 2021. Length: 6.8 cm (2.7 inches). Catch, photograph and identification courtesy of Luke Ovgard, Klamath Falls, Oregon.

Snubnose Sculpin, Orthonopias triacis. Underwater photographs taken in Mission Bay Channel, San Diego, California, September 2019. Photographs and identifications courtesy of Bob Hillis, Ivins, Utah.

The Snubnose Sculpin, Orthonopias triacis, is a member of the Sculpin or Cottidae Family, and is known in Mexico as charrasco chato. This is the only species in the genus Orthonopias, which is found in Mexican waters of the Pacific Ocean.

The Snubnose Sculpin has a large head with large eyes and a very short snout and tapers to the tail. The anus is found well back in the body and is closer to the pelvic fins than the anal fin. They have a single thin sharp preocular spine, an upper preopercular spine with 2 or more points. They vary significantly in color being able to change colors to blend into their backgrounds. They are usually mottled browns, lavenders, oranges, reds, and whites. They have an overall orange color with white ventrally, a maroon head with four distinct dark brown saddles with a brick-red center in the middle of the third saddle, pink between the first and second saddle and brown-orange between the second and third saddles. The caudal and dorsal fins have orange bars. They have a dusky spot at the anterior of the first dorsal fin. Their anal fin has 11 to 13 rays, their caudal fin is rounded, their dorsal fin is continuous with the first portion having 9 spines and the second having 16 to 18 rays; their pectoral fin has 13 to 15 rays; and, their pelvic fins have 1 spine and 3 rays. They have 6 gill rakers. They have highly visible scales on top of their head and scales along the lateral line that have thread-like extensions.

The Snubnose Sculpin is found in shallow subtidal waters on or near algae covered rock structure at depths up to 30 m (100 feet). They reach a maximum length of 9.6 cm (3.8 inches) in length. They consume algae, amphipods, copepods, polychaetes, shrimps, and snails. Reproduction involves batch spawning with each female releasing between 124 and 194 eggs. The Snubnose Sculpin 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 Snubnose Sculpin is a resident of Mexican waters of the Pacific but has a limited distribution being found from San Geronimo Island, Baja California, northward along the central and northwest coasts of Baja.

The Snubnose Sculpin is straightforward to identify and cannot be confused with any other species due to its exceedingly short snout.

From a conservation perspective the Snubnose Sculpin has not been formally evaluated. They are relatively small in stature and are encountered by divers but are of limited interest to most.