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The present study describes the ovarian development stages of wild Farfantepenaeus paulensis (Pe¤ rez-Farfante) through the combined observation of histological and visual characteristics. Twenty-¢ve females (61.872.4 g) were captured in 35^40-m deep waters o¡ southern Brazil (271S). The females were grouped according to the size and shape of their ovary and then killed. The colour of the fresh ovary was compared with a chromatic scale catalogue. Analysis of the histological sections of each ovary determined the morphological characteristics, size and frequency of the di¡erent oocyte types. Based on these characteristics, four distinct stages of ovarian maturation are proposed: stage I (immature), characterized by the presence of small basophilic oocytes (52.1719.9 mm) and ovary colour ranging from translucent to creamy; stage II (developing), with yolky oocytes (YOs) (144.2726.1 mm) and a light green colour; stage III (mature), presenting largeYOs but with cortical rods (235.0730.2 mm) and an olivebrown colour; and stage IV (spent), with atretic oocytes and the same ovary colour pattern as stage I. The gonadosomatic index ranged from 1.6 (stage IV) to 13.7% (stage III) and was closely related to the different ovarian maturation stages. The observation of visual features coupled with histological characteristics was found to represent a reliable procedure to evaluate the ovarian maturation of F. paulensis.

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Kalliapseudes schubartii (Crustacea: Tanaidacea) is a tube dwelling invertebrate living in estuarine soft bottoms with distribution along the south-east and southern Brazilian and Uruguayan coasts. Individual growth, and reproduction were examined by taking samples for a year in the estuarine region of the Lagoa dos Patos (southern Brazil). The von Bertalanffy model described growth of K. schubartii (K=4.54 y−1, L∞=13.22 mm). Reproductive activity was observed in spring and summer. No relationship was observed between total length of females and brood size. Eggs, embryos, and mancas were often observed in a marsupium. Relative growth analysis showed two levels of allometry in the growth of chelipeds of males.

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Pil1nixa brevipollex Rathbun, 1898 is a new record fo r Santa Catarina and Rio Grande do Sul. KEY WORDS. Decapoda, Pil1notheridae, distributiol1, identificatiol1, Brazi l Os Pinnotheridae são compostos por caranguejos de pequeno porte, marinhos ou estuariais. Algumas espécies apresentam carapaça membranosa. A fronte geralmente é estreita, os pedúnculos oculares e as órbitas são pequenos. Os adultos podem ocorrer livres no meio ambiente, especialmente os machos, ou associados a outros animais: comensais ou parasitas em moluscos bivalves e ascídias, sobre equ inodermados ou habitando tubos de poliquetos (WILLIAMS 1984). Os gêneros abordados neste estudo foram sugeridos por RATHBUN (1898 , 1918) que descreveu várias espécies. STAUBER (1945) e BEACH (1969) estudaram o desenvolvimento, distribuição e o ciclo de vida de Zaops oslreum (Say, \8\7). RlGHI (1967) e RODRlGUES DA COSTA (1969) registraram e listaram as espéies que ocorrem no litoral brasileiro, indicando suas associações. MELO (1971) relatou ocorrências e descreveu novas espécies. FENUCCI (197\, \975) observou a distribuição de Pinnotheridae no litoral argentino. BOOTHE (1977) estudou o gênero Pinnixa (White, 1846) na Carolina do Sul, USA. MELO (\985) analisou a distribuição das espécies de braquiúros das regiões Sudeste/S ul do Brasil. Mais recentemente GR1FFITH (1987) fez uma revisão das espécies do gênero Dissodactylus (Smith, 1870). CAMPOS & GRIFFITH (1990) criaram o gênero Clypeaslerophilus.

Antitropicality is a distribution pattern where closely related taxa are separated by an intertropical latitudinal gap. Two potential examples include Brachidontes darwinianus (south eastern Brazil to Uruguay), considered by some authors as a synonym of B. exustus (Gulf of Mexico and the Caribbean), and B. solisianus, distributed along the Brazilian coast with dubious records north of the intertropical zone. Using two nuclear (18S and 28S rDNA) and one mitochondrial gene (mtDNA COI), we aimed to elucidate the phylogeographic and phylogenetic relationships among the scorched mussels present in the warm‐temperate region of the southwest Atlantic. We evaluated a divergence process mediated by the tropical zone over alternative phylogeographic hypotheses. Brachidontes solisianus was closely related to B. exustus I, a species with which it exhibits an antitropical distribution. Their divergence time was approximately 2.6 Ma, consistent with the intensification of Amazon River flow. Brachidontes darwinianus, an estuarine species is shown here not to be related to this B. exustus complex. We suspect ancestral forms may have dispersed from the Caribbean to the Atlantic coast via the Trans‐Amazonian seaway (Miocene). The third species, B rodriguezii is presumed to have a long history in the region with related fossil forms going back to the Miocene. Although scorched mussels are very similar in appearance, their evolutionary histories are very different, involving major historical contingencies as the formation of the Amazon River, the Panama Isthmus, and the last marine transgression.

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