| Family | Scientific Name | Author | Year | Common Name |
| Myctophidae | Hygophum reinhardtii | (Lutken) | 1892 | Slender Lanternfish |
All Hygophum Species: Two Prc photophores. No photophores above lateral line. AO divided into 2 groups, AOa and AOp; Pol present. Mouth terminal, snout not projecting; jaws short, extending less than 1/2 eye diameter behind orbit. PVO1-2 in an inclined line, with PVO2 usually more than 1 photophore diameter above PVO1; all VO level. Two Pol (FAO 2002).
Hygophum reinhardtii
Unique Characteristics: Prc2 at lateral line or less than 1 photophore diameter below lateral line. VLO about midway between lateral line and outer pelvic-fin base; SAO1 behind VO2. Twenty-two to 24 (very rarely 21 or 25) anal-fin rays; caudal-peduncle length distinctly longer than dorsal-fin base. Pol1 equidistant between last AOa and Pol2. Male SCO single, ICO absent; female SCO absent, and ICO of 3-4 coalesced patches, sometimes separate (FAO 2020).
Similar Species:
Hygophum benoiti, Nonlineaar Lanternfish
Nonlinear Lanternfish, Hygophum benoiti. Prc2 at lateral line or less than 1 photophore diameter below lateral line. VLO at lateral line; SAO1 in front of or above VO2. Male SCO single, black-rimmed, and ICO absent; female SCO absent, and ICO of 2-3 patches, sometimes coalesced (FAO 2020).
Hygophum hygomii, Bermuda Lanternfish
Bermuda Lanternfish Hygophum hygomii. Prc2 at lateral line or less than 1 photophore diameter below lateral line. VLO at lateral line; SAO1 in front of or above VO2. Male SCO single, ICO absent; female SCO absent, and ICO of 1-3 irregular-shaped patches; occasional specimens with both (FAO 2020).
Hygophum taaningi, Scalelesslight Lampfish
Scalelesslight Lampfish, Hygophum taaningi. Prc2 at lateral line or less than 1 photophore diameter below lateral line. VLO about midway between lateral line and outer pelvic-fin base; SAO1 behind VO2. Eighteen to 20 (very rarely 21) anal-fin rays; caudal-peduncle length subequal to dorsal-fin base. Pol1 often over last AOa and noticeably closer to last AOa than Pol2. Male SCO single, massive, extending about 80% of supracaudal space, and ICO absent; female SCO absent, and ICO with 2-3 small, elongate patches, sometimes coalesced (FAO 2020).
References:
(FAO 2002). The living marine resources of the Western Central Atlantic. Volumes 1-3. K.E. Carpenter (ed.). Food and Agriculture Organization of the United Nations, Rome, Italy. 4099p. (Available at: http://www.fao.org/3/y4160e/y4160e00.htm).
(FAO 2020) Sutton, T.T., P.A. Hulley, R. Wienerroither, D. Zaera-Perez, and J.R. Paxton. 2020. Identification guide to the mesopelagic fishes of the central and south east Atlantic Ocean. FAO Species Identification Guide for Fishery Purposes. Rome, FAO. 2020. https://doi.org/10.4060/cb0365en.