Rivulus kayapo n. sp. (Teleostei: Cyprinodontiformes: Rivulidae): a new killifish from the serra dos Caiapós, upper rio Araguaia basin, Brazil.
Author
Wilson J. E. M. Costa
text
Zootaxa
2006
1368
49
56
http://www.zoobank.org/urn:lsid:zoobank.org:pub:268B8AA4-0A63-46E1-B4E7-563C0B0D9D3C
journal article
z01368p049
268B8AA4-0A63-46E1-B4E7-563C0B0D9D3C
[[ Genus
Rivulus
]]
The killifish genus
Rivulus Poey
constitutes the most speciose and geographically widespread assemblage of aplocheiloid fishes. A great diversity in species of
Rivulus
has long been known from Central America and the northern part of South America, including river basins draining the Guyana Shield and the western portion of the Rio Amazonas basin (Costa, 2003, 2006). However, a rich diversity of species has only recently been reported for the central part of South America, including southern tributaries of the rio Amazonas (Tocantins, Araguaia, Xingu, and
Tapajos
) and the rio
Parana-Paraguay-Uruguay
basin (Costa, 1995a, 2005).
Rivulus
is still a poorly diagnosed genus, but it contains well-corroborated monophyletic units. This is the case for an assemblage formerly known as the
Rivulus punctatus species group
(Costa, 1995a), now considered to comprise the subgenus
Melanorivulus
(Costa, 2006), a well supported clade endemic to central South America. This subgenus comprises 18 species:
Rivulus apiamici Costa
,
R. cyanopterus Costa
,
R. dapazi Costa
,
R. decoratus Costa
,
R. egens Costa
,
R. litteratus Costa
,
R. modestus Costa
,
R. paracatuensis Costa
,
R. parnaibensis Costa
,
R. pictus Costa
,
R. pinima Costa
,
R. punctatus Boulenger
,
R. rossoi Costa
,
R. rutilicaudus Costa
,
R. scalaris Costa
,
R. violaceus Costa
,
R. vittatus Costa
, and
R. zygonectes Myers
. A new species of this clade, collected in the rio
Caiapo
drainage of the upper Rio Araguaia basin, is herein described.