Many authors recognize two subspecies of C. nigripinnis: C. n. nigripinnis (Black-finned, or Dwarf, Argentine Pearl) and C. n. alexandri (Entre Rio Argentine Pearl). Others—perhaps a majority—consider each one to be a valid species in its own right. While being overall similar to each other, C. n. alexandri males have brownish, almost vertical bands on the body. C. n. nigripinnis lacks the bands but has the characteristic black fins that are indicated in both the scientific and common names.
Other common names
- Dwarf Argentine Pea
Family
- Aplocheilidae (sensu Nelson); Rivulidae (Parenti)
Subfamily
- Rivulinae {sensu Nelson)
Distribution
- Argentina.
Size
- Males up to 2in (5cm); females smaller.
Behavior
- Active; males are sometimes aggressive.
Diet
- Livefoods preferred, but other diets also accepted.
Aquarium
- Single-species aquarium, with a peat substratum and vegetation clumps. Soft, slightly acid, good-quality water required. Temperature range: 64-77F (18-25C) recommended, but slightly higher and lower temperatures are tolerated.
Breeding
- Use 1 male to 2 or 3 females. Eggs are buried in the peat. Squeeze gently to remove excess water and store in the dark for 3-4 months, but do not allow it to dry out. Resoak the eggs in aquarium water; they will begin hatching, sometimes within a few hours. Remove the females immediately after spawning, since they will be harassed by the male, which can spawn again straightaway.
