Taxonomy & naming
L353 is a DATZ L-number, a trade code from the system begun in 1988 for imported loricariids not yet identified; the form has no describing authority and no type specimens. The registry lists it as Oligancistrus. Catalog of Fishes treats that genus as a synonym of Spectracanthicus, the name PlanetCatfish uses in Spectracanthicus sp. (L353), and the atlas follows it. No second code is recorded. Night Sky Pleco is the registry's common name. The registry names Oligancistrus punctatissimus (L16), the species the atlas treats as Spectracanthicus punctatissimus, as a similar fish, and cites the Miniatlas L-Welse (2005).
Morphology
About 5.5 in total length is the registry's figure. Neither pattern nor body shape is described, so the diagnostic characters of L353 are not on record, and "night sky" is a trade name rather than a description. Oligancistrus punctatissimus (L16) is named as a similar fish; the differences between the two are what a description would have to establish.
Habitat
L353 is recorded from the Rio Iriri and the Rio Xingu near São Félix, in Pará, Brazil, in the Amazon system, in clearwater. The Xingu and Rio Iriri ecoregions follow those localities. Habitat place, substrate and sympatric fishes are not on record.
Feeding
The registry classes L353 as predominantly omnivorous but does not say whether it eats plants. In the aquarium an omnivorous pleco is usually kept on sinking pellets or wafers, frozen foods and some vegetables. Field diet data are lacking.
Mating
The registry gives no sexing characters for L353. Spectracanthicus are typically cave spawners in which the male guards the eggs and larvae in the cave, and the registry treats the cave requirement as standard for the genus.
Breeding
No aquarium breeding is recorded for L353. How it would spawn, how many eggs it lays and how the young develop are all undocumented for this form.
In the aquarium
The registry's keeping range is 79–86 °F and pH 5.5–7.5, with a recommended tank length of 39.5 in; these are aquarium figures, not field measurements. A few fish together are favoured, with a single fish possible. Plecos of this kind need clean, well-oxygenated water with some current and caves or rock cover, and territorial behaviour toward other plecos is common.
Conservation
L353 is Not Evaluated on the IUCN Red List; an undescribed form cannot be assessed until it is named. The registry records it as not on Brazil's 2012 positive list of species cleared for ornamental export and not on the 2020 negative list. Trade collection and river works affect some L-number habitats in general, with nothing specific on record for this form.