Exclamation Point Rasbora Care Guide
Boraras urophthalmoides · Freshwater Fish
What Exclamation Point Rasbora look like
The Exclamation Point Rasbora (Boraras urophthalmoides) is a diminutive cyprinid, reaching a maximum adult size of approximately 1 inch (2.5 cm), making it one of the smallest aquarium fish available. Its body is laterally compressed and exhibits a translucent golden-orange hue, which is particularly vibrant under optimal lighting conditions. A distinctive morphological feature is the dark exclamation-point mark located on the caudal peduncle, which serves as a key identification trait. The species possesses a small, terminal mouth with fine dentition adapted for grazing on microalgae and small invertebrates. The fins are delicate and transparent, with the dorsal fin positioned slightly posteriorly, contributing to its streamlined appearance. Sexual dimorphism is subtle; males tend to be slightly smaller and more vibrantly colored than females, especially during breeding periods. Defensive adaptations include its small size and schooling behavior, which help evade predation in their natural habitat.
Behavior & temperament
The Exclamation Point Rasbora is a social species that thrives in small groups, typically exhibiting a schooling behavior that enhances its safety from predators. It predominantly occupies the mid to upper water column in densely vegetated areas of its Southeast Asian habitat. Breeding behavior is characterized by egg scattering, where females release eggs among plants, and males fertilize them externally. This species is generally peaceful and exhibits low aggression levels, making it an ideal candidate for community tanks. Its temperament allows it to coexist harmoniously with other small, non-aggressive fish, although it may become skittish in the presence of larger tankmates.
Diet & feeding
In the wild, the Exclamation Point Rasbora is an omnivore, feeding on a diet that includes microalgae, small invertebrates, and detritus. In captivity, it requires a varied diet consisting of high-quality flake food, micro-pellets, and occasional live or frozen foods such as daphnia and brine shrimp to ensure optimal health and coloration.
Behind the name
Boraras (from the local name for small fish in Southeast Asia); urophthalmoides (from Greek 'oura' meaning tail and 'ophthalmos' meaning eye, referring to the distinctive marking on the tail).
Plan your tank
Check the numbers before you buy: tank volume, a stocking plan, cycle progress, water changes, and your ongoing care routine.
Keeping Exclamation Point Rasbora?
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