Boundaries

This ecoregion includes all of the coastal drainage basins and associated coastal lagoons north of the Rio Araranguá in Santa Catarina and south of the Rio Ribeira de Iguape drainage on the northern coast of the state of Paraná. The western limit is the drainage divide along the Serra do Mar.

Topography

This ecoregion rises 1700 m asl from the Atlantic Coast to the crystalline massifs of the Serra do Mar, with the southernmost extent of the range forming the Serra Geral. River valleys are filled with alluvial fan and fluvial sediments, and the coastline is marked by a barrier island/lagoonal system that reflects the shallow marine environment that once occupied this coastline (Caruso et al. 2000). Major bays and lagoons, such as the Baía Paranaguá, are flooded rifts (Dillenburg & Hesp 2009).

Freshwater habitats

The ecoregion is cut by short coastal rivers that drain the slopes of the Serra do Mar and Serra Geral. The coast is marked by rocky headlands, embayments, plains, and barriers (Dillenburg & Hesp 2009). The numerous lagoons and bays that line the coastline include Baía Paranaguá, Baía de Guaratuba, Baía da Babitonga, Lagoa da Conceição, Volta da Lagoa, Lagoa de Santo Antonio, and Laguna de Garopaba do Sul.

Terrestrial habitats

Remnants of the once extensive Atlantic moist forests characterize this ecoregion with species of Leguminosae, Sapotaceae, and Lauraceae that dominate the emergent and canopy layers. This coastal ecoregion is also distinguished from other parts of the Brazilian Atlantic moist forests by its richness of Bromeliaceae, Myrtaceae, Melastomataceae, and Lauraceae species. Coastal areas around places like Florianópolis and Baía Paranaguá are marked by mangroves (WWF 2001).

Description of endemic fishes

Thirty-six endemic species in nine families are recorded from the Southern Mata Atlântica ecoregion, representing 37% endemism. Of these 25% are loricariids, followed by 19% characids and 17% poeciliids. Fifty percent of the endemics fall into one of four genera that contain three or more endemic species: Deuterodon (Characidae), Pareiorhaphis (Loricariidae), Phalloceros (Poeciliidae), and Trichomycterus (Trichomycteridae). There are no endemic genera, although the characid Rachoviscus is restricted to the Southern and Northeastern Mata Atlântica ecoregions [331, 330].

Other noteworthy fishes

The pejerrey (Odontesthes argentinensis), located in the Lower Paraná [345], Laguna dos Patos [334], and Southern Mata Atlântica, is a marine species found also in brackish and freshwater.

Justification for delineation

The Southern Mata Atlântica falls within Gery’s (1969) East Brazilian faunal region and southeastern province and Ringuelet’s (1975) ríos costeros S.E. Brasil ichthyographic province. This ecoregion contains high endemism, and is distinguished from the Northeastern Mata Atlântica [328] by lower species endemism and no endemic genera.

Level of taxonomic exploration

Good