Rio pearlfish (Nematolebias whitei)

Scientific name: Nematolebias whitei Myers, 1942

The Rio pearlfish (Nematolebias whitei) is a freshwater fish of the family Rivulidae. In the aquarium it needs water at 20–23°C (68–73°F). Native range: South America, Laguna de Araruama basin, Das Ostras River basin, coastal plains adjacent to the mouth of S?o Jo?o River in Brazil.

Rio pearlfish care at a glance

Temperature: 20–23°C (68–73°F)

Biology

Dorsal spines (total): 0; Dorsal soft rays (total): 13-19; Anal spines: 0; Anal soft rays: 18 - 24; Vertebrae: 29 - 31. Having series of small bluish white spots, often coalesced to form continuous or fragmented line, on subdistal area of caudal fin and dark brown to black stripe on border of anal fin, adjacent and parallel to perpendicular extensions of subdistal golden transverse lines. Dorsal head profile slightly convex to nearly straight in male, gently concave to approximately straight in female.

Source: FishBase, licensed CC BY-NC 4.0.

Species facts

Scientific name: Nematolebias whitei
Family: Rivulidae (Rivulines)
Order: Cyprinodontiformes (Live bearers, Killifishes and Rivulines)
Class: Actinopterygii (Ray-finned fishes)
Maximum length: 8.0
Environment: Freshwater;; pH range: 6.5 - 7.0; dH range: 5 - 8 benthopelagic; non-migratory
Climate: Tropical
Distribution: South America: Laguna de Araruama basin, Das Ostras River basin, coastal plains adjacent to the mouth of S?o Jo?o River in Brazil.
Conservation status (IUCN): Not Evaluated
Threat to humans: Harmless
Uses: Aquarium: commercial
Resilience: High, minimum population doubling time less than 15 months (tm=0.1)