We described herein a new Hemigrammus from the río Madre de Dios and rio Mamoré basins in southeastern Peru and Bolivia. The new species possess a color pattern similar to those belonging to the Hemigrammus lunatus species-group, i.e., a broad longitudinal dark stripe across the eye and a conspicuous, narrow dark stripe along the anal-fin basis. It can be easily diagnosed from the species belonging to this group by presenting the combination of the following characters: an oval, horizontally elongated humeral blotch, 6-7 upper branch and 10-12 lower branch gill-rakers, up to five cusps on broader maxillary teeth, and by lacking a midlateral dark stripe. Comments on its putative relationships are provided. Additionally, we updated the geographical distribution of Hemigrammus lunatus and H. machadoi based on an exhaustive survey of material deposited in collections. [Species Zoobank registration: urn:lsid:zoobank.org:act:A2ED5D61-8434- 4A0F-BC5B-B496FB3DC191].
Bibliographical noteFunding Information:
We are grateful to Hernán Ortega and Nicol Faustino (MUSM), Ramiro Barriga (MEPN), Raphael Covain (MHNG), Jeff Clayton, Kris Murphy, G. David Johnson, Sandra Raredon, and Jeffrey Williams (USNM), Dave Catania, and Luiz Rocha (CAS), Jonathan Armbruster and Dave Werneke (AUM), Douglas Nelson (UMMZ), Caleb Macmahan, Kevin Swagel, and Susan Mochel (FMNH), Karsten Hartel, and Andrew Williston (MCZ), Mark Sabaj. Mariangeles Arce, and John Lundberg (ANSP), Wolmar Wosiacki, and Isaura Maschio (MPEG), Sven Kullander, Erik Ahlander, and Bo Delling (NRM), Aléssio Datovo, Michel Gianeti, and Osvaldo Oyakawa (MZUSP), and Claudio Oliveira and Ricardo Benine (LBP) for assistance during visits to their institutions and-or loan of material under their care. Eduardo G. Baena prepared Fig. 1. We are also grateful to Willian M. Ohara (UNIR) for providing data from the lots of H. changae deposited at the CBF and MNKP collections, and to Renildo Oliveira and Cárlison Oliveira (INPA) for assistance with clearing and staining specimens, as well with Fig. 2. Brian Perkins provided pictures of living specimens. The first author is funded by Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (grant #12002011001-P7). The second author is Fundação de Amparo à Pesquisa do Estado de São Paulo (grants # 2011/51532-7 and 2013/20936-0).
- Hemigrammus lunatus
- Hemigrammus lunatus species-group
- Hemigrammus machadoi
- Río Madre de Dios
- Río Mamoré