Apistogramma angayuara

By Pet Zone SD Team • November 2026

Overview

Apistogramma angayuara holds a genuine record within this genus: Sven Kullander and Efrem Ferreira's 2005 description in Neotropical Ichthyology (3(3):361–371) calls it outright "the smallest species of Apistogramma reported so far." The largest measured male came in at 24.7mm standard length and the largest female at 22.7mm — under an inch, nose to tail base, not counting the caudal fin. FishBase independently confirms essentially the same figures (2.5cm SL max for males and unsexed fish, 2.3cm SL for females). For comparison, this site's own A. helkeri is already one of the smallest species covered here at 3–4cm — angayuara runs meaningfully smaller still. The one honest caveat, raised by PlanetCatfish forum moderator Mike Wise in a 2006 thread discussing the new description, is that every measurement comes from preserved museum specimens; aquarium-raised fish sometimes grow larger than wild-caught ones, so nobody has actually tested whether a captive-raised angayuara would hold to the same ceiling, because as far as this guide's sources show, nobody has ever kept one.

The species epithet itself tells part of the story: per the original description, "angayuara" comes from a Lingua Geral word — Lingua Geral being a historical Amazonian trade language derived from Tupi — meaning "skinny" or "thin," a direct reference to its unusually elongate body shape (the body depth runs just 26.4–29.4% of standard length, slimmer than the typical apisto profile). Kullander and Ferreira described a second new species in the same 2005 paper, A. salpinction, collected from the same Rio Trombetas river system — a sibling discovery with a strikingly different fate: unlike angayuara, salpinction finally entered the wholesale aquarium trade in January 2025, two decades after its own description.

Natural Habitat

Angayuara's habitat is the real outlier here, not just its size. Most apistos covered on this site, from pertensis to the genus's many blackwater-swamp specialists, come from still or slow-moving water. Angayuara was collected directly from rapids on the Rio Trombetas in Pará State, Brazil, near the cachoeira (waterfall) Vira Mundo — the holotype itself came from a stagnant pool below the falls, but the describers also collected the species at the cachoeira Porteira, in genuinely fast-flowing water running over rocks. Those rocks support Podostemonaceae, a family of aquatic plants that grows exclusively attached to stone in strong current — a habitat signature associated with rheophilic (current-loving) fish, not the quiet floodplain pools most of this genus prefers. In the dry season, falling water levels expose rock and strand fish in isolated pools until the rains return and reconnect the system.

No source checked for this guide documents water chemistry readings taken at the actual collection sites — a real gap, not an oversight on this guide's part. Given the fast, oxygenated, rocky-bottomed habitat described, soft and only mildly acidic clearwater (rather than deep blackwater) is the most defensible inference, but it remains an inference, not a confirmed parameter.

Tank Setup

There is no aquarium-keeping record to draw tank-setup guidance from. Every detail below is this guide's own inference from the wild habitat described above, not a documented aquarium practice — treat it as a starting hypothesis, not instructions a previous keeper has already tested.

• Tank size: Not documented. Given an adult size under an inch, a nano setup would likely suffice by body size alone, but no source confirms this species has ever actually been housed in one.
• Substrate & décor: The wild habitat suggests smooth rock and current-swept surfaces rather than the leaf-litter-and-driftwood default used for this site's blackwater specialists — but again, this is an inference from locality data, not a tested aquarium setup.
• Water chemistry: Undocumented. See our general water parameters guide for how soft, mildly acidic South American water is typically built, should anyone ever need to replicate conditions for this species.
• Filtration & flow: The one thing the habitat data does support with real confidence: angayuara comes from genuinely fast-flowing rapids, the opposite of the still-water default this site recommends for most of the genus. Any attempt at keeping this species should start from stronger-than-usual flow and high oxygenation, not the gentle-flow default used elsewhere on this site.

Feeding

This is one of the few areas with genuine wild data, even though it doesn't translate cleanly into an aquarium diet. The original description includes stomach-content analysis of five wild specimens (19–24mm), and the dominant food item was rhizopods — single-celled protozoans that move and feed using temporary cytoplasmic extensions called pseudopodia, amoebas being the best-known example — followed by sponges and cladocerans (small planktonic crustaceans, the same broad group as daphnia). The authors note this is the first cichlid species on record found with a significant proportion of rhizopods in its diet, a genuinely unusual finding. No aquarium diet can replicate a rhizopod-heavy intake, but the cladoceran component suggests that daphnia and other small live or frozen zooplankton — already a staple for other tiny apistos on this site — would be a reasonable starting point if this species is ever kept. See our general feeding guide for conditioning diets used across the genus.

Temperament & Compatibility

Undocumented. No source checked for this guide records behavioral observations of angayuara in captivity, and precious little even from the wild beyond the habitat and diet notes above. Until a keeper with firsthand experience documents otherwise, the only responsible guidance is the genus-wide default: calm tankmates, and never house multiple Apistogramma species together given the hybridization risk.

Breeding

No breeding report exists for this species in any source checked for this guide — not a thin one, an absent one. The original description notes that dissected wild specimens of both sexes had well-developed gonads, confirming the collected fish were reproductively mature, but that's a dissection note, not a husbandry observation. Nothing documents courtship, spawning site preference, clutch size, or fry care for angayuara specifically. Every other species on this site that reaches the "Breeding" section can at least point to genus-standard cave-spawning behavior as an informed assumption; for angayuara, even that assumption rests entirely on its membership in a genus where cave-spawning is otherwise close to universal, not on any direct observation of this species.

Sourcing Notes

As far as this guide's sources show, Apistogramma angayuara has never been available in the aquarium trade. It's known only from scientific collection and preserved museum specimens associated with its 2005 description. A 2006 PlanetCatfish forum discussion of the new species treats it the same way — as a taxonomic curiosity, not a fish anyone might buy — and nothing found for this guide indicates that's changed since. If you see a fish offered for sale under this name, treat the claim with real skepticism and ask the seller for verifiable collection documentation; the far more likely explanation is a misapplied name for a different, more available Rio Trombetas or Rio Negro species. See our general sourcing guide for vetting an unusual or suspicious species claim.

Final Thoughts

Angayuara doesn't belong on a shopping list — it belongs on a "species to know about" list. It holds a real, citable record (the smallest Apistogramma formally described), comes from a habitat that breaks the genus's usual still-water pattern, and turned up the first rhizopod-dominant diet ever recorded in a cichlid — three genuinely distinct facts for a fish most hobbyist sources have never even mentioned. If you came here hoping to stock one, start instead with an available, well-documented species like cacatuoides or borellii. If what draws you to this genus is its taxonomic edges and the gaps in what's actually known, angayuara sits naturally alongside this site's own pertensis in the provisional "Pertensis" species group, and alongside helkeri as a lesson in just how small this genus can get.

Frequently Asked Questions

Is Apistogramma angayuara really the smallest species in the genus?

Yes, as far as the formal scientific record goes. Sven Kullander and Efrem Ferreira's 2005 description in Neotropical Ichthyology explicitly calls it "the smallest species of Apistogramma reported so far," with a largest measured male at 24.7mm standard length and a largest female at 22.7mm. FishBase independently lists the same figures (2.5cm SL max for males/unsexed fish, 2.3cm SL for females). That's smaller even than this site's own helkeri, itself one of the tiniest apistos covered here at 3–4cm. The caveat, raised on the PlanetCatfish forum by moderator Mike Wise, is that every measured specimen is a preserved museum specimen — aquarium-raised fish sometimes grow larger than their wild counterparts, so the true adult ceiling in captivity has never actually been tested.

What makes Apistogramma angayuara's habitat unusual for the genus?

Most Apistogramma species, including nearly every other one covered on this site, come from still or slow-moving water — swamps, flooded forest, quiet tributary margins. Angayuara is different: the original description collected it directly from rapids on the Rio Trombetas, including fast water running over rocks at the cachoeira (waterfall) Porteira, where Podostemonaceae (a family of plants that only grows attached to rock in fast current) covers the substrate. In the dry season, falling water levels expose rocks and leave isolated pools where fish become trapped until the water rises again. It's a genuinely atypical biotope for this genus, not a minor variation on the usual blackwater-swamp theme.

Can you keep Apistogramma angayuara in a home aquarium?

Not with any documented confidence. No source checked for this guide — FishBase, Aquatic Republic, Cichlidae.com, or the PlanetCatfish forum — records a confirmed aquarium import, a kept specimen, or a breeding report for this species. A 2006 PlanetCatfish forum thread discussing it post-description treats it as effectively unavailable, and nothing found since indicates that's changed. This page exists to document a genuinely remarkable fish, not to promise you can buy one; treat it as a species to know about rather than one to shop for.

Is Apistogramma angayuara endangered?

The IUCN Red List assessed it as Data Deficient in 2018 — genuinely unresolved, not a clean bill of health. FishBase separately estimates medium resilience (a population could double in roughly 1.4 to 4.4 years under the right conditions) and rates its vulnerability to fishing pressure as low (10 out of 100), but those are generic biological estimates drawn from its size and relatives, not a species-specific population study, and neither resolves the Data Deficient listing.

How is Apistogramma angayuara related to other species on this site?

Cichlidae.com places it in the genus's provisional "Pertensis" species group, the same group as this site's own A. pertensis. It was also described in the same 2005 paper, from the same Rio Trombetas river system, as a second new species, A. salpinction — a sibling discovery now covered on this site as well, and a striking contrast: salpinction entered the wholesale aquarium trade for the first time in January 2025, while angayuara still has no documented aquarium history at all. Separately, a 2006 PlanetCatfish forum discussion raised the possibility that angayuara may not be fully distinct from A. inornata or an aquarium form nicknamed "Kupferrücken" (Copper-back), a taxonomic question that, as far as the sources checked for this guide show, has never been formally resolved.