Fin's Fish Guide
The Rainwater killifish (Lucania parva) is a fish that lives in both fresh and salt water of the family Fundulidae that grows up to 6 cm.
Western Atlantic along the coast of North America, in shallow, vegetated coastal water, estuaries and seagrass; tolerates fresh to salt water.
Description
The rainwater killifish is a very small, stocky killifish of the family Fundulidae reaching about 6 cm. The silvery-grey body has an upturned mouth; breeding males develop orange edges to the fins. The species is remarkably salinity-tolerant and lives in shallow, vegetated coastal water, estuaries and seagrass along the American Atlantic coast, from nearly fresh to full seawater. As a hunter just below the surface it eats midge larvae, small zooplankton and small crustaceans. It attaches its eggs by threads to water plants and seagrass. Through its great numbers it is an important prey fish and is, also outside its native range, sometimes used as a bait and aquarium fish.
Frequently asked questions
How do you recognise the Rainwater killifish?
The Rainwater killifish has a torpedo-shaped body, is mainly silver-grey and shows a plain pattern. Very small, stocky killifish with an upward-facing mouth; in the spawning season the male develops orange fin margins.
Where does the Rainwater killifish live?
The Rainwater killifish lives in both fresh and salt water and is mostly found around algae or seagrass beds. Western Atlantic along the coast of North America, in shallow, vegetated coastal water, estuaries and seagrass; tolerates fresh to salt water.
How big does the Rainwater killifish get?
The Rainwater killifish grows to a maximum of about 6 cm. On average the species is around 4 cm.
Is the Rainwater killifish dangerous to humans?
No, the Rainwater killifish is harmless to humans. None required: this species is harmless to humans.
Is the Rainwater killifish edible?
The Rainwater killifish is not usually eaten.
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All data
Identification
Appearance
Habitat & distribution
Behaviour & biology
For anglers
Safety
Status & sources
Same genus Lucania
More from the family Fundulidae
Want the complete picture on the Rainwater killifish?
Point your camera at the fish and Fin names the species in seconds. Free, and the Rainwater killifish is one of 12,519 species in the app.