Conchos pupfish
Cyprinodon eximius
© FishBase (CC BY-NC)The Conchos pupfish (Cyprinodon eximius) is a tiny endemic freshwater fish found in the Conchos River basin of northern Mexico. Reaching only about 5 cm, it is popular among conservationists rather than anglers, known for its bright coloration and adaptation to spring habitats.
Basic Information
Family
Cyprinodontidae
Max Size
5 cm
Habitat
freshwater
Climate
temperate
Best Season
Late spring to early summer when water temperatures are 20‑25 °C
Best Time
Early morning or late afternoon when surface insects are active
Distribution
No distribution map available
Fishing Tips for Conchos pupfish
- Use ultralight gear (2‑4 ft rod) with a 2‑4 lb test line to feel subtle bites.
- Employ tiny live baits such as daphnia, mosquito larvae, or finely split earthworms.
- A micro float or small bobber set very low will keep the bait just above the substrate where pupfish feed.
- Patience is key – fish are shy; approach slowly and avoid casting large shadows.
Top Fishing Locations for Conchos pupfish
Cuatro Ciénegas Biosphere Reserve
MexicoWorld-renowned spring-fed wetlands with abundant pools where the native Conchos pupfish thrives; anglers must obtain a special permit and use lightweight tackle.
Best: March to May
Río Conchos at Ocampo
MexicoUpper reaches of the Rio Conchos host remnant populations of Conchos pupfish; accessible via local guide services, but fish are scattered among rocky riffles.
Best: April to June
Laguna de los Molinos
MexicoA shallow lagoon within the Cuatro Ciénegas basin, known for clear water and dense aquatic vegetation that shelters pupfish; requires careful approach to avoid disturbing habitat.
Best: May to July
IMTA Research Ponds, Monterrey
MexicoControlled ponds maintained by the Mexican Institute of Fisheries for breeding programs; pupfish are abundant and easily caught with fine nets, ideal for educational outings.
Best: Year-round
Río Grande Near Ojinaga
MexicoA small, isolated stretch where a few Conchos pupfish have been introduced; fishing here is challenging due to strong currents and low fish density.
Best: September to November
Sierra Madre Private Conservation Reserve
MexicoRemote highland reserve protecting native aquatic habitats; limited access and strict catch‑and‑release policy make catches rare but highly prized.
Best: July to September
Market Prices
Recommended Fishing Equipment for Conchos pupfish
Recommended Equipment
Best bait: Daphnia, mosquito larvae, tiny earthworm pieces