Danionella priapus is a species of Danionella endemic to India.[2] It is sexually dimorphic and, like other species in the genus, possesses a skeleton with fewer bones than the closely related zebrafish. However, it has a number of distinguishing features which differentiate it from others in the genus, with the most notable example being the conically projecting genital papilla between the funnel-shaped pelvic fins of males.[3]
^Britz, Ralf. “Danionella Priapus, a New Species of Miniature Cyprinid Fish from West Bengal, India (Teleostei: Cypriniformes: Cyprinidae).” Zootaxa, vol. 2277, no. 2277, Magnolia Press, 2009, pp. 53–60, https://doi.org/10.11646/zootaxa.2277.1.4.
