Eiconaxius carinatus (Bouvier 1925) caracteriza-se, principalmente, por apresentar carenas laterais do rostro lisas, mero da quela maior com carena dorsal lisa, palma da quela maior exibindo carena dorsal bem nítida e dedos da quela menor de comprimento inferior ao da palma. Um exemplar foi coletado ao largo do Estado do Maranhão (00º 08' N e 44º 32' W) a 247 m de profundidade. A área de ocorrência anteriormente conhecida abrangia a Flórida e Antilhas (Santa Cruz e São Vicente), entre 161 e 339 m. Este trabalho registra pela primeira vez a família para o Brasil.

Eiconaxius carinatus (Bouvier 1925) is characterized, mostly, by smooth rostral lateral carinae, merus of major chela with smooth dorsal carina, palm of major chela with dorsal carina evident and length of fingers of minor chela less than the palm length. One specimen was collected off the state of Maranhão (00º 08' N and 44º32'W) in a depth of 247 m; this species was known previously from Florida and West Indies (Saint Croix and Saint Vincent), in depths between 161 and 339 m. This record is the first record of this family for Brazil.

This paper presents a contribution to the study of the Crustacea, Decapoda of Brazil, including identification keys and informations on species range. Data related to the species of family Portunidae are published.

The authors have studied the geographical distribution of 33 freshwater prawn species found in Brazil and surrounding areas, as part of a research project which views the development of a national technology for the freshwater prawn culture. The fauna comprises litoral species found in lowlands along the coast, in areas limited at the south by the 15ºC isotherm for the average air temperature of the coldest month, and continental species, which can be separated in tropical, subtropical and temperature ones, whose occurrence areas were delimited by the 20ºC and 15ºC average air temperature of the coldest month.

Prawn growth in intensive culture ponds depends upon the cultured species and internal (nutrition state) and external (pond condition) factors. To obtain growth taxa in aquaculture for the "canela" prawn (Macrobrachium amazonicum), experiments were carried out at Amapá and Pernambuco, Brazil. The initial prawn population of Amapá ponds carne from different places of the Amazon river, while those from Pernambuco from hatcheries of the Departamento de Oceanografia da Universidade Federal de Pernambuco. Physico-chemical and biological analyses of the water were made at the same time. The growth rate was estimated through collections of samples of about 10% of the initial population, with measures of the orbital length of each individual. Ponds' harvests were done when most of the population presented an orbital length equal to or larger than 80 mm. The present results showed 70 mm average size after 3-4 months of the post-larvae settlement to be the ideal for harvesting, favouring the utilization of this species for intensive aquaculture. Data on correlation, orbital and total growth, and weight gain were obtained during prawn growth.

This paper presents a list of crustacean decapods occuring in the State of Maranhão coast, Brazil, based on the study of collections of the Departamento de Oceanografia (Universidade Federal de Pernambuco) and Laboratório de Hidrobiologia (Fundação Universidade do Maranhão) and on litterature records. There are recorded 149 species (37 species of Natantia and 112 species of Reptantia).

The studied area is limited by São Francisco River mouth, to the South, and by Coroa das Lavadeiras, State of Rio Grande do Norte, to the North. This area presents only two seasons, summer and winter. During the summer, the freshwater inflow is smaller, the southeast winds are dominant, the temperature, the salinity and the transparence of water are high. The winter is characterized by greater freshwater inflow, east winds, smaller temperature and low salinity and transparence only in coastal and estuarine waters. Off São Francisco River mouth the water conditions are inverted and the salinity and transparence variations affect all continental shelf. In the soft bottoms are found the following communities: a) Supralittoral beach; 2) Mediolittoral beach; 3) Infralittoral beach; 4) Circalittoral mud (São Francisco mouth); 5) Circalittoral gravel mud (São Francisco mouth).