Dawkinsia is a genus of barbs in the carp family Cyprinidae, endemic to India and Sri Lanka and concentrated in the fast-flowing hill streams of the Western Ghats. The genus was split out from the old wastebasket genus Puntius in the early 2010s, when researchers separated its members by a distinctive breeding-season trait: males develop long, filamentous extensions on the dorsal fin rays, a feature that gives several species their common 'filament barb' names. Bodies are moderately deep and laterally compressed, with the bold barring or striping typical of many South Asian barbs, and adults reach a modest 3–7 in depending on species.
The genus includes some of the aquarium trade's best-known Indian barbs. The Denison barb (Dawkinsia denisonii), sold as the roseline shark or red-line torpedo barb, is a long-standing favourite for its torpedo shape and bold red-and-black lateral stripe, while the Arulius barb (D. arulius) was one of the earliest South Asian barbs in the hobby and remains popular for its trailing dorsal filaments. Both do best kept in a group in cool, oxygen-rich, current-swept water, reflecting their hill-stream origins. The conservation picture is serious: eight of the eleven species the atlas tracks are listed Endangered, a legacy of habitat loss in the Western Ghats compounded, for the Denison barb in particular, by heavy wild collection for the aquarium trade; one species is a CARES conservation priority.