Freshwater

African brown knifefish

Xenomystus nigri

The body of this fish is unusual: it is flattened ventrolaterally and elongated, giving it a …

Arapaima

Arapaima gigas

The body of the arapaima is elongated and compressed from the sides. It is covered with …

Argentine pearlfish

Austrolebias bellottii

The Argentine pearlfish has a laterally compressed, fusiform (spindle-shaped) body with a rounded profile. Males are …

Black Molly

Poecilia sphenops

The Black Molly has an elongated body. Females tend to be more rounded in appearance. The …

Campylomormyrus curvirostris

Campylomormyrus curvirostris, gnathonemus curvirostris, campylomormyrus rhynchophorus.

The snout of Campylomormyrus curvirostris is highly elongated and curved downward like a trunk, with a …

Campylomormyrus numenius

Campylomormyrus numenius

Campylomormyrus numenius possesses a highly elongated, ventrally curved rostrum, analogous to an elephant's trunk, terminating in …

Constancia’s seasonal killifish

Cynolebias constanciae

The body of Constancia's seasonal killifish (Cynolebias constanciae) is elongate and slightly laterally compressed.

Eastern bottle-nosed mormyrid

Mormyrus longirostris

The eastern bottle-nosed mormyrid has such a distinctive appearance that it cannot be confused with any …

Eastern mosquitofish

Gambusia holbrooki

The body of the Eastern mosquitofish is moderately elongated, not tall, and laterally compressed. It is …

Finescaled four-eyed fish

Anableps microlepis

Anableps: Greek, ana = up + Greek, blepo, blepsis, -eos = glance, sight.The elongated cylindrical body …

Frankfish

Gymnarchus niloticus

The Frankfish has a long and slender body. It possesses four small bony gills on both …

Green swordtail

Xiphophorus hellerii

Green swordtails have elongated, narrow bodies that are flattened on the sides. They also have large …

Guppy

Poecilia reticulata

Guppies exhibit pronounced sexual dimorphism, with males and females differing in size, shape, and colouration. Males …

Least killifish

Heterandria formosa

Least killifish differ little in body shape from their closest relatives, the Poecilia. They have an …

Mosquitofish

Gambusia affinis affinis

The male anal fin is modified and is an intermittent organ for introducing sperm into the …

Peters's elephant-nose fish

Gnathonemus petersii

The elephantnose fish has a moderately deep, laterally compressed body with a distinctive sharp, funnel-shaped snout. …

Porous seasonal killifish

Cynolebias porosus

The Porous seasonal killifish has a fusiform (spindle-shaped) body that is laterally compressed. The snout is …