American flagfish

About

The American flagfish (Jordanella floridae) earns its name honestly. The male's body is patterned with rows of red and green iridescent spots against a dark background, a close enough match to the Stars and Stripes that the comparison stuck. It's a native of Florida and the surrounding region, where it lives in slow, weedy waters including ponds, lakes, and sluggish streams, sometimes tolerating mildly brackish conditions. Unlike true killifish, this species is not seasonal and will spawn more or less continuously when kept warm, depositing eggs in small batches attached to algae or plant surfaces. Males stake out territories and intensify their coloration when competing for females, and dominant fish can be genuinely feisty. Not just toward rivals but toward unrelated tankmates, with fin-nipping a real concern. For that reason it does best either alone or in a carefully chosen community with robust, similarly-sized fish and plenty of cover. Its other claim to fame is appearing in record books for producing fewer eggs per clutch than almost any other fish. On the practical side, the flagfish is a genuinely useful algae grazer and will work through soft filamentous growth that many other fish ignore, which makes it appealing for planted tanks, provided its temperament is accounted for.