Rasboroides is a small genus of danionid fishes endemic to Sri Lanka, where its two species -- Rasboroides pallidus and R. vaterifloris -- are confined to the streams and slow-flowing waters of the island's wet zone. Closely related to Rasbora, they share the same slender, laterally compressed body, forked tail, and a single dorsal fin set well back over the body, reaching a modest adult size of about 1.5 in. Both species favor shaded, often tea-stained forest streams with dense marginal vegetation, a habitat type that has shrunk considerably across Sri Lanka's wet zone as land is cleared for agriculture and development.
In the hobby, R. vaterifloris -- the Pearly rasbora, sometimes traded under other local names -- is the better known of the two, prized for a warm orange-gold sheen along its flanks and fins; R. pallidus, the Fire rasbora, is less commonly seen but shares the same peaceful, schooling temperament typical of small danionids. The conservation picture here is genuinely serious: both species are assessed as Endangered, reflecting how restricted and pressured Sri Lanka's wet-zone endemic freshwater fauna has become, and any aquarium stock is best sourced from captive-bred lines rather than wild collection.