Slender Lanternfish, Lampanyctus tenuiformis

Slender Laternfish, Lampanyctus tenuiformis. Fish collected in a deep-water trawl net off Point Loma, California, August 2010, by H.J. Walker, Jr., Scripps Institute of Oceanography, La Jolla, California, Length: 11 cm (4.3 inches).

The Slender Lanternfish, Lampanyctus tenuiformis, is a member of the Lanternfish or Myctophidae Family, that is also known as the Thin Laternfish and in Mexico as pez lámpara fino. Globally, there are twenty-two species in the genus Lampanyctus, of which twelve are found in Mexican waters, four in the Atlantic, six in the Pacific, and two in both the Atlantic and the Pacific Ocean.

The Slender Lanternfish has a long rectangular bodies. They are reddish-brown with silvery patches. Their anal and dorsal fins are transparent. Their caudal fin is forked and dusky in color. Their head has a very short pointed snout, a slanted forehead, large eyes, a large mouth that extends well past the eyes, and thick lips. They have a limited number of randomly positioned photophores on their body and a prominent row of photophores ventrally. Their anal fin has 17 to 19 rays and their dorsal fin has 13 to 15 rays. They have no spines.

The Slender Lanternfish is a mesopelagic species found at depths between 40 m (130 feet) and 2,896 m (9,500 feet). They reach a maximum of 15.6 cm (6.1 inches) in length. They migrate vertically toward the surface at night to feed on zooplankton, then retreat toward the bottom at night to avoid predation. They are heavily preyed upon by numerous marine fish and mammals. Reproduction is oviparous with pelagic planktonic eggs and larvae. Although common, the Slender Laternfish 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 Slender Lanternfish is a resident of all waters of both the Atlantic and the Pacific Oceans.

The Slender Lanternfish, due to its body profile, cannot be confused with any other species.

From a conservation perspective the Slender Lanternfish has not been formally evaluated. They are small in stature, seldom seen by humans, and are of limited interest to most.