Blackline Tilefish

Blackline Tilefish, Caulolatilus cyanops

Blackline Tilefish, Caulolatilus cyanops. Fish caught from coastal waters off Ft. Lauderdale, Florida, February 2022. Length: 32 cm (13 inches). Catch, photograph and identification courtesy of George Brinkman, Guelph, Ontario, Canada.

Blackline Tilefish, Caulolatilus cyanops. Fish caught from coastal waters off Ft. Lauderdale, Florida, February 2022. Length: 24 cm (9.4 inches). Catch, photograph, and identification courtesy of Ben Cantrell, Sebastian, Florida.

The Blackline Tilefish, Caulolatilus cyanops, is a member of the Tilefish or Malacanthidae Family, that is also known as the Black Tilefish and in Mexico as domingo. Globally, there are ten species in the genus Caulolatilus, of which seven are found in Mexican waters, five in the Atlantic and two in the Pacific Ocean.

The Blackline Tilefish has a robust and quadrangular body with a depth that is 21 to 34% of standard length with a relatively deep and rounded head. They are an overall violet-blue, with numerous dark reticulated lines and a dark stripe along their upper back. They transition to white ventrally. They have a ridge along the nape that has a yellow tinge. Their head has silver cheeks with a greenish-blue oblique bar that runs from their eye up to the top of the lip. Their spiny dorsal fin has orange membranes. They have a dark blotch above the pectoral fin base. The caudal fin has lobes that are tinged in yellow. Their gill cover has one short blunt spine. Their anal fin has 1 or 2 two spines and 22 to 23 rays; their caudal fin is slightly concave; their dorsal fin has 7 spines and 23 or 24 rays; and their pectoral fins have 16 or 17 rays. They have 17 to 21 gill rakers. Their body is covered with rough scales.

The Blackline Tilefish is a demersal species that is found at depths between 45 m (150 feet) and 495 m (1,625 feet) over sandy, muddy and rubble substrate. They are known to reside in burrows. They pursue prey by both sight and smell with their diets consisting primarily of a variety of invertebrates including benthic worms, crabs, gastropods, sea cucumbers, sea stars, sea urchins, shrimp, and smaller fishes. They reach a maximum of 60 cm (2 feet 0 inches) in length and up to 11.0 kg (24 lbs, 3 oz) in weight. As of January 1, 2023, the International Game Fish Association world record stood at 0.68 kg (1 lb 8 ounces) with the fish caught in coastal waters off Bimini in July 2018. Reproduction is oviparous.

The Blackline Tilefish is similar to and can be easily confused with the Blueline Tilefish, Caulolatilus microps (dorsal fin with vertical rows of yellow spots), the Great Northern Tilefish, Lopholatilus chamaeleonticeps (caudal fin with 8 or 9 rows of yellow spots), the Goldface Tilefish, Caulolatilus chrysops (broad yellow patch under the eye that extends to the nostril; caudal fin with yellow spots) and the Gulf Bareye Tilefish, Caulolatilus intermedius (dark bar under eye).

The Blackline Tilefish is a resident of Mexican waters of the Atlantic Ocean being found throughout the Gulf of Mexico; they are absent from along the east coast of the Yucatán Peninsula in the Caribbean.

From a conservation perspective the Blackline Tilefish Whitefish is currently considered to be of Least Concern with stable, widely distributed populations. They are considered to be an esteemed human food fish and are actively pursued by both commercial fishermen and recreational anglers. They are caught primarily by hook and line with a limited number caught by commercial trawls. They are believed to have some protection from trawlers due to their burrowing habits. Their catch levels are poorly monitored as they are often mixed in with Gulf Bareye Tilefish. They are considered an excellent food fish and sold commercially in all local fish markets live, fresh, and frozen.