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The 'Red Cherry shrimp', Neocaridina davidi is a small freshwater caridean shrimp living, originally, in various kinds of inland water bodies around Asian countries. This shrimp has reached several countries for ornamental use; however, basic information on the biology of the species is still scarce in the literature. Its early post embryonic development morphology has not yet been described. This paper focused on the production and the development of early post-hatching stages of N. davidi, its male secondary sexual features, observation of the gonads and the presence of females with embryos. The larval development of N. davidi was almost suppressed as noted by the presence of relatively large-sized eggs, first stage hatching as a decapodid; and the tail fans were present only from the 2nd post-hatching stage. A biological important consequence of the presence of this Red Cherry shrimp species in the Neotropics is its potential release into nature, which could cause its rapid dispersion affecting populations of other indigenous caridean freshwater shrimps.

Beurlenia araripensis Martins-Neto and Mezzalira, 1991 (Decapoda: Caridea) and Paleomattea deliciosa Maisey and Carvalho, 1995 (Decapoda: Penaeoidea) are reviser baseated upon new and better preserved samples. The new specimens were found in the Santana Formation, Araripe Basin, Northeast Brazil, respectively in the Crato and Romualdo members. B. araripensis is represented by a well preserved specimen, where is possible to see a cephalothorax with antennal and branchiostegal spines, rostrum with 14 dorsal spines, and telson with posterior spines. This material permits a better characterization of the species' morphology and its placement in Palaemonidae. The Dendrobranchiata material of P. deliciosa, found in the bituminous shale of Romualdo Member, is for the fi rst time recorded in clusters of fragmentary parts that suggest mass mortality and morphologies that point to a planktonic lifestyle, as occurs with extant forms of sergestids.

Morphological descriptions of the first larval stages of Persephona mediterranea, P. lichtensteinii and P. punctata (Leu-cosiidae: Eballinae) from the South Atlantic are provided, with comparisons among the morphometry of the species. Adetailed description and eight morphometric measurements were made for each larva, and a discriminant function analysiswas used to interpret the data set. The species differed significantly in certain morphological and morphometric features.These characteristics may help in the identification of species of Leucosioidea found in the South Atlantic, and can be an important tool in ecological studies, supporting the identification of planktonic morphotypes at the species level.

ABSTRACT. The population biology of the burrowing crab Neohelice granulata (Dana, 1851) from a mangrove in Jabaquara Beach, Paraty, state of Rio de Janeiro, Brazil (23º13'04"S and 44º42'47"W), was studied with respect to the following traits: size-frequency distribution, recruitment, reproductive period, fecundity, and sex ratio. Specimens were sampled monthly from April, 2003 to March, 2004, at the river margins during low tide periods. Size, sex, presence of eggs, and stage of the female gonad were recorded. Ovigerous females had their eggs removed and counted. The reproductive period was continuous and the highest frequency of ovigerous females was recorded in the fall and winter. Mature gonads were found throughout the year and recruitment was continuous but more intense during the summer. The fecundity of N. granulata (30028.3 ± 10861.2 eggs) was high in comparison to studies in other localities. In general, the proportion of males was similar to that of females (1:0.92); however, males were predominant in the fall (1:0.77) and winter (1:0.75). All the information available so far on the reproduction of N. granulata involves populations from subtropical salt marshes; therefore, comparative studies including other habitats, such as mangrove forests, are needed to further understand the environmental influences on the population and reproductive biology of semiterrestrial crabs.