Taxonomy & naming
Lignobrycon myersi was originally described in 1956 by the Brazilian ichthyologist Paulo de Miranda Ribeiro as Moojenichthys myersi. It was later placed in the monotypic genus Lignobrycon, and it remains the only recognised species in that genus, within the family Triportheidae (the keeled hatchet-characins and their relatives) in the order Characiformes. The species epithet honours the American ichthyologist Dr. George Sprague Myers (1905–1985), a major figure in the study of Neotropical freshwater fishes.
Given the very narrow, poorly surveyed range of this genus, records of it are thin outside the primary taxonomic and conservation literature, and no meaningful hobby or trade history has been documented. Nothing in the cited sources indicates a recent generic reassignment beyond the 1998 move into Lignobrycon, so this account keeps the currently recognised combination.
Morphology
Lignobrycon myersi is a small characin, with FishBase recording a maximum standard length of about 3.5 in — a genuinely modest adult size, not a juvenile figure, and one that sets it apart from the far larger, more famous members of this atlas's "Piranhas & Pacus" grouping. Detailed morphological description is sparse in the available sources; the fish is consistent with the general build of small pelagic open-water characins in this family, and specific data on fin structure, dentition or colour pattern was not found in the cache. Rather than guess at details not documented, this account leaves those points open.
Habitat
This species is a pelagic (open-water) fish of clear, dark (black-water) coastal river systems in Bahia, northeastern Brazil, with its type locality in the Rio do Braço system near Ilhéus. Field data collected from the Rio Braço describes a river roughly 33–82 ft wide and 5–10 ft deep, with a sandy-muddy bottom studded with boulders, flowing through Atlantic coastal forest, and a recorded collection temperature of about 70 °F.
No pH or general hardness data for this species was found in the cache, so no figure is given here rather than an invented one. The narrow, forest-associated range and black-water character of its home rivers make this a fish of the fragmented Atlantic Forest coastal drainages rather than the Amazon, Orinoco or Paraná systems that hold most of this group's larger, better-known relatives.
Feeding
FishBase records the diet of Lignobrycon myersi as mosquito larvae and other aquatic invertebrates, consistent with a small, opportunistic insectivore foraging in open water rather than a detritivorous grazer or a predator of other fish. No aquarium feeding data has been documented for this species; a diet mirroring its wild insectivory — small live and frozen invertebrate foods alongside a quality prepared diet sized for a fish under 3.5 in — would be the reasonable inference, but this is not confirmed by any source in the cache.
Mating
No courtship or pairing behaviour has been documented for Lignobrycon myersi in the sources available. Nothing in the cache describes sexual dimorphism, colour changes during spawning condition, or how pairs (if any) form in the wild or in captivity. Rather than assume a courtship pattern typical of other small open-water characins, this account states plainly that the data is not available.
Breeding
There is no documented breeding record for Lignobrycon myersi in the wild or in the aquarium among the sources consulted here. Given its placement among small open-water Characiformes, an egg-scattering strategy without parental care would be broadly consistent with its relatives, but no source confirms this for the species itself, and none of the material found addresses fecundity, spawning triggers, egg character, or incubation. This account does not assign a breeding mode that has not actually been documented for this fish.
In the aquarium
Lignobrycon myersi has essentially no aquarium-keeping literature — no care guides, forum accounts or trade history were found among the cited sources, which points to a fish that is rarely if ever seen in the hobby. What can be said with confidence is scale: at a documented maximum of about 3.5 in, this is a small fish suited to a modest aquarium footprint, not a species that will outgrow a home tank the way many of its family's larger relatives do.
As a pelagic species from clear, dark, moderately cool (around 70 °F) coastal-forest water, any attempt to keep it should start from those wild parameters — soft, tannin-stained water, modest current, and temperatures on the cooler side of typical "tropical" community tank ranges — rather than defaulting to generic warm, blackwater Amazon-characin advice. Because it is a narrow-range Near Threatened endemic with no established aquaculture, any specimen encountered in trade should raise real questions about legality and wild-collection impact; this is not a fish to acquire casually.
Conservation
Lignobrycon myersi is assessed as Near Threatened by the IUCN Red List, reflecting its narrow endemic distribution across a small number of coastal river systems in Bahia, northeastern Brazil. A 2023 genetic-diversity study of natural populations (published via PubMed/NCBI) reconfirms the Near Threatened status and underscores the conservation interest in this restricted-range species.
The principal pressures on its habitat are deforestation, pollution and river impoundment within the fragmented Atlantic Forest coastal drainages it depends on — the same suite of threats facing many other narrow-range fishes in this heavily deforested region of Brazil. The species is also noted as occasionally subject to illegal trade despite Brazilian protections, though it has no meaningful established presence in the legitimate aquarium hobby.