Brazilian scientists have described a new species of Hemigrammus tetra from the Paran River drainage in southeastern Brazil.
The new species, named Hemigrammus parana by Manoela Marinho, Fernando Carvalho, Francisco Langeani and Flvio Tatsumi in a recent issue of the journal Zootaxa, is distinguished from other members of the genus in having a combination of the following characters: absence of a humeral spot; presence of a roughly triangular or rectangular conspicuous black caudal spot, extending to the tip of the middle caudal-fin rays and having its greatest depth at the base of the caudal fin; 3"4 simple and 18"23 branched anal-fin rays.
Picture kindly supplied by Manoela Marinho.
The species is named after the river drainage in which it occurs.
According to the authors, the new species is very common and specially abundant in backwater margins, from 0.3 to 1.30 m depth, occurring associated with Poaceae and macrophytes (Ceratophyllum sp., Egeria densa, Eichornia spp., Ludwigia sedorde, and Salvinia sp.).
Stomach contents examination of two specimens showed a large volume of Spirogyra sp., Cladocera, sediments (sand) and unidentified organic matter.
Several species were collected syntopically with Hemigrammus parana, the most frequent were Astyanax altiparanae, Crenicichla britskii, Geophagus proximus, Gymnotus carapo, Hoplias malabaricus, Hyphessobrycon eques, Laetacara sp., Metynnis maculatus, Moenkhausia sp., Pamphorichthys hollandi, Roeboides descalvadensi, Satanoperca pappaterra, Serrapinnus notomelas, and Serrasalmus maculatus.
For more information, see the paper: Marinho, MMF, FR Carvalho, F Langeani and FL Tatsumi (2008) A new Hemigrammus Gill from upper rio Paran system, Southeastern Brazil (Characiformes: Characidae). Zootaxa 1724, pp. 52"60.