Lampanyctus parvicauda

Lampanyctus parvicauda is a lanternfish, a member of the family Myctophidae, found in the eastern Pacific from central Baja California, Mexico, to Chile ^[1]. It is a small open-water animal: the largest recorded is about 11 cm standard length ^[1].

The data cited here on its presence off northern Chile come from research hauls with a midwater trawl, not from direct observation ^[2]. The IUCN Red List assesses it as Least Concern ^[3].

The genus name, Lampanyctus, comes from Greek: lampas, meaning torch, and nykte, meaning night ^[4]. The species was described by Parr in 1931 ^[5].

The known range runs from central Baja California to Chile; larvae have been recorded as far north as the Ensenada area in northern Baja California ^[1]. At the southern end, a research cruise off northern Chile, between 18°30' and 30°30'S, caught the species only in summer and only in the northern part of the area, north of 26°S ^[2].

Vertically it is a midwater fish. An annotated checklist cites records from 9 to 342 m depth, and there are deeper catches, at 1370 m and 2325 m, but these come from the maximum depth fished by trawls, so the fish may have been higher up ^[1]. FishBase gives a range of 100 to 1320 m ^[4].

The maximum published size is 11.2 cm standard length ^[1]. In the catches off northern Chile, 12.5 % of the specimens were longer than 60 mm, and two individuals of 104 and 106 mm came close to the 110 mm that the author cites as the largest known in the literature ^[2].

The 54 specimens from that cruise were taken in an oblique midwater trawl, all of them in night-time sampling; the author notes that almost all myctophids were caught at night, which suggests that by day and by night they occupy different depths ^[2].

In the hauls off northern Chile, Lampanyctus parvicauda was among the numerous myctophids in the midwater trawl during the summer cruise: 54 specimens, 8.1 % of that trawl's total ^[2]. It is regarded as a species of the Peru-northern Chile zoogeographic district, which a proposal cited by the same author places between 3° and 24°S ^[2].

The study suggests that, in summer, this species and 6 others extend their distributions southward, and links this to the southward advance of the subtropical water mass in that season; this is the author's hypothesis, not a direct measurement of fish movements ^[2].

The IUCN Red List places Lampanyctus parvicauda in the global category Least Concern (LC) ^[3].