1 kinds · tap one for a closer look
Peaceful surface dweller; needs a tight lid as it can leap out.
273 species in our list are a good match.
Peaceful surface dweller; needs a tight lid as it can leap out. Keep a group with calm tankmates.
Small floating live and frozen foods such as fruit flies, daphnia and bloodworms.
Tap a food to see what it is.
Hard to sex; mature females are presumed to be the larger, rounder-bodied fish.
Common problems. Tap one to see the signs. This is a guide, not a diagnosis.
Egg-scatterer (rarely bred) ·
No aquarium breeding has been recorded.
Needs a large group in mature, stable conditions; pairing is hard to control.
Roomy, planted tank with very soft acidic water (pH 5-6.5), subdued light and fine-leaved plants or a spawning mat.
Rain-season style changes: soft cool water changes, a small temperature rise and heavy live feeding.
unknown
Infusoria then brine shrimp nauplii; survival is poor without very clean water.
A tiny blackwater hatchetfish from the upper Orinoco and the Rio Negro. It was named by George S. Myers (1927) after his wife, Martha. Like all hatchetfish it does not truly fly: it makes a powerful pectoral-powered jump, so it needs a lid.
George S. Myers described this small hatchetfish in 1927, one of several new South American fishes he named in that period. It lives in tea-coloured blackwater rivers, especially around the Rio Negro. Most aquarium specimens are still wild-caught and exported from the Amazon region.
First described by George S. Myers in 1927.
15 facts checked with sources
Valid name. Piggott et al. (2011, cited by Seriously Fish) found at least three cryptic species within the Rio Negro populations, so the name may be split in future. Gery (1977) treated C. schereri as a subspecies of C. marthae; C. schereri is now a separate species.
Eschmeyer's Catalog of Fishes: Carnegiella species · FishBase: Carnegiella marthae summaryLegacy has no family. Not affected by the 2024 tetra family reshuffle (Acestrorhamphidae).
FishBase: Carnegiella marthae summary · Eschmeyer's Catalog of Fishes: Carnegiella speciesSeriously Fish 2.8 cm SL; FishBase 2.9 cm SL max (preserved specimens) but notes aquarium specimens reach 3.5 cm TL. Larger live figure (3.5 cm TL) kept.
FishBase: Carnegiella marthae summary · Seriously Fish: Carnegiella marthaeLegacy 24-28 lies within Seriously Fish 20-28; FishBase 23-27.
Seriously Fish: Carnegiella marthae · FishBase: Carnegiella marthae summarySeriously Fish (preferred for husbandry) 4.0-7.0; legacy minimum 5 is within but range starts lower. FishBase narrower at 5.5-6.5. A blackwater species: soft, acidic water.
Seriously Fish: Carnegiella marthae · FishBase: Carnegiella marthae summaryLegacy has no hardness. Seriously Fish 1-10 kept; FishBase gives up to 4 dH.
Seriously Fish: Carnegiella marthae · FishBase: Carnegiella marthae summary60 x 30 cm base x 30 cm height = 54,000 cm³ = 54 L. Legacy 100 L is more generous than the sourced minimum. Needs a tight lid.
Seriously Fish: Carnegiella marthaeSeriously Fish recommends 10 or more; legacy 6.
Seriously Fish: Carnegiella marthaeTimid; keep with small, calm fish.
Seriously Fish: Carnegiella marthaeSeriously Fish rates it Easy (6 of 8 measures), but wild fish need soft acidic water, a group and a tight lid; legacy moderate is a defensible editorial choice.
Seriously Fish: Carnegiella marthaeLegacy has no range. Catalog of Fishes gives a broader country list (Bolivia, Peru) that likely includes the closely related populations.
Seriously Fish: Carnegiella marthae · FishBase: Carnegiella marthae summary · Eschmeyer's Catalog of Fishes: Carnegiella speciesLegacy (females deeper in the belly) agrees.
Seriously Fish: Carnegiella marthaeLegacy says seldom bred; Seriously Fish has no record of captive breeding at all. In the wild small fish move into flooded forest to feed and reproduce during the wet season.
Seriously Fish: Carnegiella marthaeLegacy origin (Rio Negro and Orinoco) confirmed. The dark pectoral-fin edge in the legacy text was not checked against a source.
Seriously Fish: Carnegiella marthae