A Swedish researcher has identified a new species of cichlid fish in the Xingu river drainage in Brazil.
An adult male of Krobia xinguensis (Erik Åhlander)
Cichlids are fish species belonging to the family Cichlidae, one of the most popular fish families in the fishkeeping hobby. They live in fresh and brackish waters, and can be found in Asia, Africa, Central and South America.
A paper, published in the journal Zootaxa, describes the newly identified species called Krobia xinguensis.
This fish was discovered in 1964 by Harald Schultz who sampled three specimens in the Batovi river, a headwater of the Xingu river in Mato Grosso. But it has remained undescribed until now.
“K. xinguensis is described from localities in the headwaters and in the lower part of the rio Xingu,” wrote Dr. Sven Kullander of the Swedish Museum of Natural History, the sole author of the paper.
“It is distinguished from the other two species in the genus, K. guianensis and K. itanyi, primarily by deeper caudal peduncle, and details of the color pattern, including contrasting interorbital stripes and a small dark spot anteriorly on each side of the lower jaw.”
K. xinguensis measures about 6 cm (2.4”). Sexes are very similar, with slightly shorter soft dorsal and soft anal fins, and pelvic fin in females.
“Upper lip, lachrymal, part of cheek, anterior and posterior margins of opercle, and pectoral axilla red or orange,” Dr. Kullander described. “Bases of most flank scales marked with short red or orange vertical stripe.”
The species name xinguensis refers to the Xingu, the river basin inhabited by this fish.
“The presence of a species of Krobia in a southern tributary of the Amazon is interesting in the light of a limited number of genera with representatives on the Guiana and Brazilian shields only, but absent from other parts of the Amazon basin as well as the rest of South America,” Dr. Kullander wrote in the paper.
The author also noted that K. xinguensis is now available from the ornamental fish trade, where it is handled as Krobia “Red cheek” or similar expressions, emphasizing the red markings on the head and anterior side in living specimens.
