Julianas
Julianas is a genus of freshwater crabs that belongs to the family Brachyuridae. The genus was first described by J. L. Smith in 1925 based on specimens collected from riverine habitats in northern South America. Members of Julianas are characterized by a carapace that is oval to slightly broader at the posterior, with distinct lateral dimpled depressions. The claws are robust, with the palm bearing a series of tubercles that aid in gripping submerged substrates. The species exhibit a carapace coloration that ranges from pale brown to dark ochre, often with irregular mottling that provides camouflage against detritus. The telson and uropods are relatively short, and the second and third limbs in males possess chelae with noticeable setae.
Three species are currently recognized within the genus: Julianas amazonica, Julianas onca, and Julianas corvina. J.
Ecologically, Julianas crabs contribute to the breakdown of organic matter by feeding on decaying plant material