TankMatesTankMates
Sign in
Encyclopedia / Livebearers / One-spot livebearer
★New · no ratings yetPicture coming

Variations

1 kinds · tap one for a closer look

One-spot livebearer

Phalloceros caudimaculatus · Dwarf toothcarp, Caudo, One spot livebearer, Pheasant livebearer

Peaceful and busy near the surface.

Local price coming soon
· real AED shop prices, never conversions
7 cmBody length, without tail ✓
16–22 °CTemperature ✓
7–8pH ✓
50 LSmallest tank ✓
Add to my tankCompare
Tank mates
Check your own mix →
Not recommended
  • They need different temperatures (16–22 °C vs 23–29 °C). No setting suits both.
  • Only a narrow pH range suits both: exactly 7.
Not recommended
  • They need different temperatures (16–22 °C vs 24–28 °C). No setting suits both.
Not recommended
  • They need different temperatures (16–22 °C vs 23–28 °C). No setting suits both.
With conditions
  • Only a narrow temperature range suits both: 21–22 °C.
  • Only a narrow pH range suits both: exactly 7.
With conditions
  • Only a narrow pH range suits both: exactly 7.
Compatible
Compatible
Compatible
Compatible
Compatible

136 species in our list are a good match.

Facts checked against sources on 16 Oct 2026. ✓ means a source backs it; ? means no reliable source yet. See sources

Care and water

Hardness ✓5–25 dGH
Group size ?6 or more
Temperament ?Peaceful
Swims at ?Top
Care level ✓Moderate
Diet Omnivore
Lifespan ?Unknown
Size in shops 2–4 cm
Growth Medium

Behavior

Peaceful and busy near the surface. Males are tiny and constantly chase females, so keep more females.

Food

Flakes, micro pellets and small live or frozen foods; likes algae.

Tap a food to see what it is.

Male or female

Males are much smaller (about 3.5 cm) with a prominent gonopodium; females are larger, to about 6-7 cm.

Health

Common problems. Tap one to see the signs. This is a guide, not a diagnosis.

Breeding

Livebearer · Easy

Easy livebearer. Keep more females than males; with good feeding and dense planting the fry are safe with the adults.

Pairing

One male with 3 or more females.

Setup

Planted 40 L tank with floating plants and no strong flow.

What starts it

Warm water and a varied diet.

Eggs

10-50 young per brood; gestation about 24 days (FishBase) to 4-6 weeks depending on temperature (Seriously Fish). Fry eat microworms and newly hatched Artemia at once.

Raising the fry

Crushed flake and baby brine shrimp; the fry are tiny and need cover.

Common mistakes
  • Too many males
  • No hiding cover
  • Large tankmates
Full breeding guide, day-by-day plan and simulator →

Where it lives in the wild

RegionSouth-eastern South America – southern Brazil, Uruguay & Argentina
HabitatCoastal streams, ponds and ditches
Native rangeAbout 800 km across
See it on the world map

The story of the one-spot livebearer

A tough, cool-water livebearer from southern Brazil, Uruguay and Argentina, known as the dusky millions fish. It comes in spotted ('reticulatus') and golden ('auratus') hobby forms; it is best kept cool and ideally in a species tank. Released for mosquito control, it is now invasive in Australia, New Zealand and parts of Africa.

German zoologist Reinhold Hensel described this livebearer in 1868. It is a small, hardy fish with a single dark spot, and has been introduced to other countries including Australia.

First described by Reinhold Hensel in 1868. Named for 'Caudimaculatus' means spotted tail.

  • It tolerates cooler water than most livebearers.
  • A golden-spotted form is common in aquariums.
  • A 2008 study split it into many similar-looking species.

Sources

13 facts checked with sources