Rock prickleback – Xiphister mucosus

The Rock Prickleback, scientifically known as Xiphister mucosus, is a fish species belonging to the Stichaeidae family. This fish is a common inhabitant of the rocky intertidal and subtidal zones along the Pacific coast of North America, ranging from Alaska to Baja California.

Description & Characteristics

The Rock Prickleback is a slender, elongated fish with a slightly compressed body. Its maximum size is around 58.0 cm, although individuals usually reach lengths of 20-30 cm. The fish has a distinctive pointed head with a small mouth and prominent eyes. Its body is covered in small, cycloid scales. The Xiphister mucosus is characterized by a continuous dorsal fin running along its back, with spines that are more developed in the anterior portion. The anal fin is also long and continuous, extending almost to the caudal fin. The overall coloration of the Rock Prickleback is brown to olive-green, often with dark blotches or bands.

Habitat and Occurrence

The Rock Prickleback is a highly adaptable species, thriving in a variety of marine environments. It can be found in the intertidal zone, tide pools, and on rocky reefs. The Xiphister mucosus prefers habitats with abundant algae and crevices, where it can find shelter and forage. Its depth range extends from the surface to approximately 18.0 meters, encompassing both the subtidal and sublittoral zones. The Rock Prickleback is typically found in the neritic zone, which encompasses the shallow waters of the continental shelf.

Taxonomy

The species Xiphister mucosus belongs to the Class: Teleostei, Order: Perciformes, and Family: Stichaeidae. This classification places it within a group of ray-finned fishes characterized by their diverse body forms and complex life cycles.

Feeding

The Rock Prickleback is an opportunistic carnivore, feeding on a wide range of invertebrates, including crustaceans, amphipods, isopods, copepods, worms, and mollusks. The Xiphister mucosus also consumes algae and zooplankton. Its diet varies depending on the availability of prey in its habitat.