Devil’s Hole pupfish  (Cyprinodon diabolis)

Description

Found only in a single desert spring in Nevada, USA, this tiny fish has the most restricted range of any vertebrate (2). The smallest of all pupfish, this unique species lacks pelvic fins and the distinctive barring so common among other pupfish (2) (4). The fins are large and rounded with dark edges, and the dorsal and anal fins are located far back on the body (5). As with all pupfish, the sexes of this species are differently colored. Males are silvery with iridescent neon-blue sides, which change to metallic green or golden under different angles of light (4) (6). The female is smaller and more yellowish-brown, with the young resembling females (4) (7).

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