Algeria

The Sahara toothcarp, Apricaphanius saourensis, is endemic to the Oued Saoura, an endorheic river basin in Algeria that drains into the Sahara. Described in 2006, it differs from A. iberus and A. baeticus in its mottled body patterning. In 2004 it was found only at Mazzer, and introduced Gambusia is thought to have extirpated it from its other localities. The describers suggest it should be considered critically endangered.

The footless toothcarp, Tellia apoda, is endemic to a small area of the Tellian Atlas mountains in northeastern Algeria. It lacks ventral fins and sits apart from the other western Aphanius in genetic terms. The last collection was in 1990, and rumours suggest it may already be extinct through introduced Gambusia affinis and agricultural pollution. Fish in the hobby should all come from the population at Aïn M'Lila.

The grass carp, Ctenopharyngodon idella, is a large cyprinid native to the Amur River system in eastern Russia and northeastern China. Adults typically reach 800 to 1200 mm, making it a wholly unsuitable aquarium subject, though an albino form is traded. Widely introduced for aquaculture and weed control, it has caused serious damage to natural waters, and unwanted fish should never be released.