Argyropelecus lychnus

Argyropelecus lychnus Garman, 1899

Languages: English

Overview

Description

Dorsal-fin rays 9; anal-fin rays 12; pectoral-fin rays 10–11; total gill rakers 16–18; vertebrae 35–37. Medium to large species often exceeding 60 mm SL; body deep, depth at end of dorsal greater than 1.5 into SL; dorsal blade high, height about 2.5 times into its length; postabdominal spines of about equal size, anterior one slightly smaller, not smoothly curving but blunted or squared; upper preopercle spine long, directed posteriorly and usually ventrally; lower spine usually curved slightly anteriorly or straight down; jaws large, teeth recurved especially in lower jaw, no large canines; gill rakers medium to short, dentate; first preanal photophore usually lower than third; spiny scales present in adults below subcaudal photophores; the gap made by the anal pterygiophores contains two haemal spines lacking pterygiophores; in preservative, pigment dark dorsally, diffuse on trunk with small, light pigment spots on midline.

Author(s): Kenaley, Christopher
Rights holder(s): Kenaley, Christopher

Type Information

Type specimen(s)

Lectotype: USNM 57885.

Author(s): Kenaley, Christopher
Rights holder(s): Kenaley, Christopher

Type locality

South of Cuiba Island, Panama, 6°17'N, 82°05'W, Albatross station 3360, depth 1672 fathoms.

Author(s): Kenaley, Christopher
Rights holder(s): Kenaley, Christopher

Synonymy

Data on Catalog of Fishes

View data on Catalog of Fishes here.

Author(s): Kenaley, Christopher
Rights holder(s): Kenaley, Christopher

Description

Diagnostic Description

Two separate postabdominal spines; anal subcaudal gap fewer than 2.0 times anal-preanal gap; dorsal rays. Both postabdominal spines of about equal length and size; anterior margin of posteriormost abdominal keel scale almost vertical; greater than 3.5 times body depth. No pair of enlarged canines in lower jaw; anteriormost postabdominal spine squared or blunt (except very small individuals), not curving evenly forward; upper preopercular spine extends well beyond posterior border of preopercle; no pigment on outermost caudal rays. Dorsal blade high, blade height greater than 2.7 mm for SL 25–50 mm, greater than 3.8 mm for SL greater than 50 mm; body robust; spiny scales present below subcaudal photophores (fish greater than 30 mm SL); pigment spots minute along posterior midline; upper preopercle spine usually curved ventrally, never dorsally.

Author(s): Kenaley, Christopher
Rights holder(s): Kenaley, Christopher

Size

Exceeds 60 mm SL.

Author(s): Kenaley, Christopher
Rights holder(s): Kenaley, Christopher

Ecology and Distribution

Distribution

Absent from the Atlantic; represented possibly by a single sample from the Indian Ocean. Primarily restricted to the tropical Pacific; found in abundance in the eastern Pacific between 35° N and 35°S; distribution narrows across the equatorial Pacific as far as 160˚W; a moderate catch from the lesser Sunda Islands indicates a possible transequatorial distribution in the Pacific.

Author(s): Kenaley, Christopher
Rights holder(s): Kenaley, Christopher

Habitat

Concentrated between 300 m and 400 m off California by day, with the highest concentration near 400 m; by night major concentrations occur from 200 m to 350 m, with no marked indication of geographical variation in depth.

Author(s): Kenaley, Christopher
Rights holder(s): Kenaley, Christopher

References

References

Baird RC. 1971. The Systematics, Distribution, and Zoogeography of the Marine Hatchetfishes (family Sternoptychidae). Bulletin of the Museum of Comparative Zooology 142(1):1–128.

Author(s): Kenaley, Christopher
Rights holder(s): Kenaley, Christopher

Main Reference

Baird RC. 1971. The Systematics, Distribution, and Zoogeography of the Marine Hatchetfishes (family Sternoptychidae). Bulletin of the Museum of Comparative Zooology 142(1):1–128.

Author(s): Kenaley, Christopher
Rights holder(s): Kenaley, Christopher