have been done in Brazil, and even in South America or worldwide (Ghiold and
Hoffman 1986; Price et al. 1999; O’Hara and Poore 2000; Martinez 2008). This is
probably due to the relatively low number of researchers dedicated to this kind of
study, particularly in Brazil, and lack of reliable information on taxonomy and
distribution ranges. Although information on the occurrence and distribution of
echinoderm species in Brazil still seems to be insufficient regarding the great
length of the country’s coastline. New records and new species have been
described recently as emphasized later in this chapter.
These three patterns of distribution are much correlated with the hydrographical
features (i.e. marine currents and water masses) of the Brazilian coast, as described
above (see Introduction). Changes in species composition occur markedly at the
Cabo Frio region, where upwelling often brings sub-Antarctic water (the South
Atlantic Central Water, SAWC) to shallow depths. Therefore, there are features of
a temperate environment at a such usually tropical latitude (22°S), which could
explain the distribution pattern of some species from Cabo Frio to Uruguay (Rio de
la Plata) and the occurrence of tropical and subtropical fauna at Cabo Frio, such as
the sea stars Astropecten cingulatus (tropical), Astropecten brasiliensis (subtropical), Echinaster (Othilia) guyanensis (tropical), Echinaster (Othilia) brasiliensis
(subtropical), Asterina stellifera (subtropical) and the sea urchin Paracentrotus
gaimardi (subtropical).
Historically, the South Atlantic Ocean was formed during the Cretaceous
(ca. 135 My) when South America was separating from Africa and Antarctica/
Australia (the so-called Gondwana paleo-continent). Therefore, species composition on the Brazilian continental shelf should be similar to those at the margins of
Africa and Antarctica/Australia and different from the marine fauna of north of the
South America (‘‘Tethyan’’), because there is no marine connection between the
south and the north regions of the Atlantic (Floeter et al. 2009). South America and
Africa became effectively separated by a deep-sea barrier during the Paleocene (ca.
60 My). About the same time, a connection between the marine biotas of Brazil and
the Caribbean was formed. During the Eocene (ca. 50 My), Australia and Antarctic
became separated and also the latter and South America. Each step of the history of
South American west coast might mark the evolution of the Brazilian marine biota,
at least in shallow water (Floeter et al. 2009). In general, this seems to be true for
echinoderms and other marine organisms because the three patterns of species
distribution are similar for different taxa. Furthermore, the echinoderm fauna of
Brazilian waters is currently very similar to those of the Caribbean, as for other
groups of marine invertebrates. This similarity may also be due to the effects of
relatively recent dispersal capacity and colonization, as well as ancient extinctions
of species at the Brazilian continental shelf.
Comparing the number of species described worldwide and for Brazilian
waters, one can notice that there are not as many species of Brazilian echinoderms
as expected from the great length of the country’s coastline. This is probably due
to the low number of researchers dedicated to the study of echinoderms in Brazil.
Therefore, information on the occurrence and distribution of echinoderm species
in Brazil is insufficient.
9 Echinoderm from Brazil
317
Hoffman 1986; Price et al. 1999; O’Hara and Poore 2000; Martinez 2008). This is
probably due to the relatively low number of researchers dedicated to this kind of
study, particularly in Brazil, and lack of reliable information on taxonomy and
distribution ranges. Although information on the occurrence and distribution of
echinoderm species in Brazil still seems to be insufficient regarding the great
length of the country’s coastline. New records and new species have been
described recently as emphasized later in this chapter.
These three patterns of distribution are much correlated with the hydrographical
features (i.e. marine currents and water masses) of the Brazilian coast, as described
above (see Introduction). Changes in species composition occur markedly at the
Cabo Frio region, where upwelling often brings sub-Antarctic water (the South
Atlantic Central Water, SAWC) to shallow depths. Therefore, there are features of
a temperate environment at a such usually tropical latitude (22°S), which could
explain the distribution pattern of some species from Cabo Frio to Uruguay (Rio de
la Plata) and the occurrence of tropical and subtropical fauna at Cabo Frio, such as
the sea stars Astropecten cingulatus (tropical), Astropecten brasiliensis (subtropical), Echinaster (Othilia) guyanensis (tropical), Echinaster (Othilia) brasiliensis
(subtropical), Asterina stellifera (subtropical) and the sea urchin Paracentrotus
gaimardi (subtropical).
Historically, the South Atlantic Ocean was formed during the Cretaceous
(ca. 135 My) when South America was separating from Africa and Antarctica/
Australia (the so-called Gondwana paleo-continent). Therefore, species composition on the Brazilian continental shelf should be similar to those at the margins of
Africa and Antarctica/Australia and different from the marine fauna of north of the
South America (‘‘Tethyan’’), because there is no marine connection between the
south and the north regions of the Atlantic (Floeter et al. 2009). South America and
Africa became effectively separated by a deep-sea barrier during the Paleocene (ca.
60 My). About the same time, a connection between the marine biotas of Brazil and
the Caribbean was formed. During the Eocene (ca. 50 My), Australia and Antarctic
became separated and also the latter and South America. Each step of the history of
South American west coast might mark the evolution of the Brazilian marine biota,
at least in shallow water (Floeter et al. 2009). In general, this seems to be true for
echinoderms and other marine organisms because the three patterns of species
distribution are similar for different taxa. Furthermore, the echinoderm fauna of
Brazilian waters is currently very similar to those of the Caribbean, as for other
groups of marine invertebrates. This similarity may also be due to the effects of
relatively recent dispersal capacity and colonization, as well as ancient extinctions
of species at the Brazilian continental shelf.
Comparing the number of species described worldwide and for Brazilian
waters, one can notice that there are not as many species of Brazilian echinoderms
as expected from the great length of the country’s coastline. This is probably due
to the low number of researchers dedicated to the study of echinoderms in Brazil.
Therefore, information on the occurrence and distribution of echinoderm species
in Brazil is insufficient.
9 Echinoderm from Brazil
317