Fish, Cubatão River basin, Atlantic Rainforest stream, Paraná, Brazil

The freshwater ichthyofauna of the Cubatão River basin was studied. This drainage belongs to the Atlantic rainforest biome in Paraná state coastal region, southern Brazil. Considering fish collection data and extensive new collections, 41 species were listed of the families Characidae, Erythrinidae, Crenuchidae, Curimatidae, Heptapteridae, Pseudopimelodidae, Callichthyidae, Trichomycteridae, Loricariidae, Gymnotidae, Cichlidae, Anablepidae, Poeciliidae, and Synbranchidae. The river studied showed the ichthyofaunistic pattern of the coastal drainages of the Atlantic rainforest biome of southeastern Brazil, characterized by a high degree of endemism. A key for species identification is provided.


Introduction
The coastal drainages in the Atlantic rainforest biome of southeastern Brazil present a rich and diversified freshwater ichthyofauna, with a high rate of speciation and a high degree of endemism (Bizerril 1994;Castro 1999;Ribeiro 2006). Such facts are probably related to concentration of a high number of isolated river basins by a series of mountain rages forming valleys in this region. These topographic and physiognomic characteristics allow the formation of a great number of environments, which allow the occurrence of a great number of species, each one adapted to a particular habitat (Menezes 1996).
The Cubatão River basin belongs to the Atlantic rainforest dominium, and it is located in an ichthyofaunistic region which comprises coastal streams and rivers between southern Rio de Janeiro and northern Santa Catarina states (Menezes 1988;Weitzman et al. 1988). Because of the lack of information about freshwater fish from coastal rivers of state of Paraná, this study aims to provide a list of species of the Cubatão River basin, giving basic information support to projects related to fish biology and conservation.

Material and methods
The Cubatão River basin headwaters are located nearby Guaricana Reservoir (aprox. 25°40' S, 48°40' W), in São José dos Pinhais municipality, in the first plateau of state of Paraná, and flows into the Guaratuba bay, in the southern region of the Atlantic coast of Paraná (Maack 2002). Its most important tributaries are Arraial, Cubatãozinho, and São João rivers ( Figure 1).
The list of species is based on the examination of more than 500 lots of fishes belonging to the Museu de História Natural Capão da Imbuia (MHNCI), along with material collected in nine field expeditions made between February and October 2004 in the Reflorestadora Banestado in Guaratuba municipality (aprox. 25°49' S, 48°47' W).
The specimens were collected with gill nets (2; 2.5; 3; 3.5; 4 and 5 cm stretched mesh), fishing rod and pot gears. Captured specimens were fixed in the field in 10% formalin solution and brought to the laboratories of the MHNCI. Fish were collected with IBAMA authorization 96/2004 (process 02017.003718/2003-55).

Results and discussion
Forty one freshwater fish species were recorded in the Cubatão River basin, belonging to 14 families and six orders ( Hypostomus cf. punctatus), which probably will be split into other species when taxonomically revised.
The noteworthy abundance of the order Siluriformes (22 species) may be correlated with habitat characteristics, specifically with the predominance of riffle areas in the upper stretches and submerged marginal vegetation in the lower stretches. The Cubatão River basin also presents a great variety of predominant substrates, with sandy, rocky, and gravelly types according to the portions of the riffles areas.
Species belonging to groups taxonomically poorly known, such as Astyanax, Characidium, Hypostomus, and Rineloricaria could be endemic for the region. There is considerable evidence that the coastal drainages in the Atlantic Rainforest Biome from eastern Brazil between southern Rio de Janeiro and northern Santa Catarina states present a rich and diversified freshwater ichthyofauna, with a high number of endemic species (Weitzman et al. 1988;Bizerril 1994;Ribeiro 2006). These drainages are inhabited basically by small-sized fish species, which dwell in streams or shallow water of rivers, showing sometimes a high rate of speciation and a high degree of geographic endemism (Castro 1999).
The aquatic habitats from Atlantic rainforest are threatened by anthropogenic activities, such as deforestation and the extensive land use for agriculture and urban area development. Considering that the forest cover is very important for foraging activities of mostly small-sized Atlantic rainforest fish, such as several species registered herein, the Cubatão River basin deserve better attention in the planning of new protected areas.     39' Crests inconspicuous on the head; pectoral girdle exposed only laterally; a brown blotch on the caudal-fin base, with a small light area on the middle of the blotch 40 40 Head slightly triangular in dorsal view; mouth width 50 % or less in head length .. Schizolecis sp.