A new species of Asian bagrid catfish has been described in the latest issue of the icthyological systematics journal Zootaxa.
Heok Hee Ng of the University of Michigan's Museum of Zoology described Rita macracanthus from fish collected in the Indus River drainage of South Asia.
The fish has previously been considered Rita rita (a species that has turned up in recent UK imports). Indeed, existing dichotomous keys to the genus say that the new species is actually R. rita.
However, Ng's statistical analyses of the characters show that R. macracanthus has longer dorsal and pectoral fin spines, a longer premaxillary tooth band and a narrower caudal peduncle.
Helpfully, Ng's also provided an updated dichotomous key to help others identify Rita species.
For more details see: Ng, HH (2004) - Rita macracanthus, a new riverine catfish (Teleostei: Bagridae) from South Asia. Zootaxa, 568: 1-12.