A method for selective determination of tributyltin in the presence of Sn(IV) by combining hydride generation inductively coupled plasma optical emission spectrometry (HG-ICP OES) and solid phase extraction (SPE) using baker's yeast is proposed. The procedure is based on selective retention of TBT by the yeast at pH = 6. Detection limit of 1.9 µg L-1 and quantification limit of 6.3 µg L-1 were obtained. TBT and San(IV) were determined in the range of 0-25 µg L-1 and the proposed approach was applied to analyze river water, sea water and biological extracts, with recoveries of 114, 101 and 86%, respectively.

Macrobrachium birai Lobão, Melo & Fernandes, 1986, espécie de camarão de água doce do Brasil, foi capturada no Rio Branco, Cananéia, Estado de São Paulo, Brasil. No início do desenvolvimento embrionário os ovos têm cor verde oliva e tamanho médio de 0,60 x 0,43 mm. As larvas foram criadas, individualmente, a temperatura média de 25ºC. O desenvolvimento larval de Macrobrachium birai é do tipo prolongado, constituído de 15 estágios morfológicos de zoea e o decapodito. A metamorfose foi atingida em 144 dias de cultivo, através de 44 ecdises. As mudas ocorreram em intervalos de dois a oito dias e em média com 3,3 dias. As larvas de M. birai possuem algumas características morfológicas que podem diferenciá-las das larvas de M. olfersii (Wiegmann, 1836).

Macrobrachium birai Lobão, Melo & Fernandes, 1986, a native Brazilian species of freshwater shrimp, was captured along the coast of Rio Branco, Cananéia, state of São Paulo, Brazil. The eggs in early development were green and the average size was 0.60 x 0.43 mm. The larvae were reared in laboratory at average temperature of 25ºC. Macrobrachium birai has a prolonged larval development, with 15 morphological zoeal stages and the decapodito. The metamorphose was obtained in 144 days, through about 44 ecdysis. The molts occurred from two to eight days, in average of 3.3 days. The larvae of the M. birai present some morphological characteristics distinct from that of M. olfersii (Wiegmann, 1836).

Ovigerous females of Pachygrapsus transversus (Gibbes, 1850) were collected on the Praia Dura and Saco da Ribeira beaches, Ubatuba, São Paulo, Brazil. Larvae were individually reared in a climatic room at 25ºC temperature, salinities of 28, 32 and 35‰ and under natural photoperiod conditions. The best rearing results were observed at 35%o salinity. Seven zoeal instars were observed, drawing and described in detail. The data are compared with those obtained for P. gracilis (Saussure, 1858).