Pacific Scabbardfish, Lepidopus fitchi

Pacific Scabbardfish, Lepidopus fitchi. Fish caught from coastal waters out of 550-foot water off Los Barilles, Baja California Sur, July 2023. Length: 43 cm (17 inches). Catch and photograph courtesy of Chip Shapley, Los Barriles, Baja California Sur.

Pacific Scabbardfish, Lepidopus fitchi. Fish caught from coastal waters out of 550-foot water off Los Barilles, Baja California Sur, July 2023. Length: 48 cm (19 inches). Catch and photograph courtesy of Chip Shapley, Los Barriles, Baja California Sur. Identification courtesy of Dr. Ross Robertson, Smithsonian Institute, Panama City, Panama.

The Pacific Scabbardfish, Lepidopus fitchi, is a member of the Cutlassfish or Trichiuridae Family, that is also known as the Black Scabbardfish and the Ribbonfish and in Mexico a pez cinta. Globally, there are six species in the genus Lepidopus, of which two species are found in Mexican waters of the Pacific Ocean.

The Pacific Scabbardfish has an elongated and strongly compressed ribbon-like body that tapers to a very small forked caudal fin. They have a uniform silvery chrome appearance being slightly darker dorsally. Their large head has a convex upper profile rising from the snout to the dorsal fin origin, large eyes, and a large mouth that extends to the front margin of the eyes that has projecting lower jaw with an upward hooked tip and 3 fangs at the front. Their anal fin is in the mid-third of the body and has 2 spines and 41 to 50 rays; their dorsal fin originates above the gill covers and has 9 spines and 78 to 87 rays and is continuous, without a notch, tapering from front to back; their pectoral fins are inserted below the mid-line of the body and have 12 rays; and, their pelvic fins are minute. They have 35 + 50 vertebrae and 7 + 10 gill rakers. Their lateral line originates below the third and fourth dorsal rays and slopes gently downward to the caudal peduncle. They do not have scales.

The Pacific Scabbardfish is a benthopelagic species that is found at depths between 150 m (490 feet) and 500 m (1,640 feet). They reach a maximum of 2.1 m (6 feet 11 inches) in length and 1.4 kg (3 lbs 1 oz). They are known to make Diehl migrations during certain periods of the year. They are a schooling species that feed on cephalopods, euphausiids and small fishes. The Pacific Scabbardfish 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.

In Mexican waters the Pacific Scabbardfish is found in all waters of the Pacific Ocean north of Manzanillo, Colima including throughout the Sea of Cortez.

The Pacific Scabbardfish is a straightforward identification and the only Scabbardfish found in northern Mexican waters of the Pacific Ocean.

From a conservation perspective the Pacific Scabbardfish has not been formally evaluated. Fossil records indicate the family members date to the Oligocene to Quaternary Periods, 34 to 1,800 million years ago. They are exceedingly rare and seldom seen by humans and thus of limited interest to most.