Abstract The objective of this study was to investigate some life history traits of the palaemonid shrimp Typton carneus collected from a reef in northeastern Brazil. Samples of the sponges Amphimedon compressa, A. viridis, Desmapsamma anchorata, Dysidea etheria, Haliclona implexiformis and Tedania ignis were analyzed and shrimps were removed from them. A total of 41 individuals were found in Te. ignis, three in H. implexiformis and one in D. etheria; the latter two sponges are new records of sponge hosts for Ty. carneus. Of the specimens associated with Te. ignis, 24 were males, 10 ovigerous females, six non-ovigerous females and one juvenile male. Fecundity varied between 19 to 56 eggs (37 ± 14) per female, and the mean egg volume was 0.033 ± 0.010 mm³. Eleven heterosexual pairs were obtained. Characteristics of the pairs suggest a monogamous mating system for the studied population, such as: the absence of sexual dimorphism in weaponry and body size and presence of paired non-brooding and brooding females carrying eggs in different development stages; and a sex ratio that does not differ from the expected 1:1. However, the lack of size-assortative pairing as well as the low proportion of pairs, compared to solitary individuals, have been observed in polygamous mating systems.

Abstract The association of the caridean shrimps Anchistioides antiguensis (Schmitt, 1924) and Typton gnathophylloides Holthuis, 1951 with the sponges Dysidea janiae (Duchassaing & Michelotti, 1864) and Amphimedon viridis Duchassaing & Michelotti, 1864, respectively, is reported for the first time. The material was collected in coral reefs surrounding Santa Barbara Island, Abrolhos Archipelago, Bahia, Brazil. The shrimps occupied different locations inside the sponges. Previous records of associations between these carideans and other hosts were revised and the possible type of association between the shrimps and their hosts is discussed. The occurrence of the sponge A. viridis in the Abrolhos Archipelago is also reported for the first time.

Abstract The ghost shrimp Ctenocheloides almeidai Anker and Pachelle, 2013 was described based on a single specimen collected at Ponta Verde, Maceió, state of Alagoas, northeastern Brazil. Here, we report the species from Porto Seguro, Bahia (~16º23'S), extending its distribution in the Brazilian coast in approximately 7 degrees south from the type locality in Maceió, Alagoas (~9º40'S). Notes on morphological variation of the species are provided based on the present material.

ABSTRACT The occurrence of the alien alpheid shrimp Athanas dimorphus Ortmann, 1894 is reported for the first time for the state of Pernambuco, northeastern Brazil, based on two ovigerous females collected at Praia do Paraíso, near the Suape Harbor (08º21'29.9"S 34º57'00.9"W). The species, native from the Indo-West Pacific region, was previously reported from two other Brazilian states (Ceará and São Paulo), also occurring in localities with nearby harbors. The presence of ovigerous females suggests that the species was successfully introduced into the area. The main possible introduction vectors for A. dimorphus in Pernambuco and the dispersal potential of the species along the Brazilian coast are discussed.

ABSTRACTThe objective of this study is to report new occurrences of five species of snapping shrimps of the genus AlpheusFabricius, 1798 in Brazil and, thus, contribute to the knowledge of their zoogeography. The southern limit of distribution of A. formosus Gibbes, 1850 and A. peasei (Armstrong, 1940) is extended from Paraná to Santa Catarina and from Bahia to Rio de Janeiro, respectively. The northern distribution limit of A. pouang Christoffersen, 1979 and A. verrilli (Schmitt, 1924) is substantially extended from São Paulo to Pará and from Bahia to Pará, respectively. Finally, A. rudolphi Almeida & Anker, 2011, previously known from Ceará and Alagoas, is recorded for the first time in Pernambuco, filling a gap in its known distribution.

We provide an updated checklist of the snapping shrimps of the genus Alpheus Fabricius, 1798 (Crustacea: Alpheidae) from the Brazilian coast, as well as a key for their identification. The checklist was based on an exhaustive analysis of the literature published up to now, supported by analysis of material of 24 of the 33 species presently recorded from Brazil. Illustrations of the main diagnostic characters are provided to facilitate the identification process, as well as color photographs of 16 species collected by the authors, to facilitate the identification of fresh specimens. For each species, we provide information on the distribution and a list of previous records for the Brazilian coast. Comments on dubious records or taxonomic remarks are provided when appropriate. Finally, the zoogeography of the species is briefly discussed.

The decapod crustaceans inhabiting dead portions of the fire-coral Millepora alcicornis Linnaeus, 1758 and coral rubble were surveyed in six reef areas on the coast of the state of Bahia, Brazil, in 2011. A total of 453 specimens belonging to 39 species in the infraorders Stenopodidea (family Spongicolidae), Caridea (families Palaemonidae, Alpheidae, Hippolytidae, and Processidae), Axiidea (family Callianassidae), Gebiidea (family Upogebiidae), Anomura (family Porcellanidae), and Brachyura (families Majidae, Pilumnidae, Domeciidae, Panopeidae, and Grapsidae) were collected. Members of the families Alpheidae and Porcellanidae were prominent, with 14 and 9 species, respectively. Of the species collected, the alpheid shrimp Alpheus peasei (Armstrong, 1940) is recorded for the first time in the southwestern Atlantic. Microprosthema semilaeve (von Martens, 1872), Corallianassa hartmeyeri Schmitt, 1935, and Petrolisthes marginatu Stimpson, 1859 also had their known geographic ranges extended along the western Atlantic. Alpheus nuttingi (Schmitt, 1924), Synalpheus scaphoceris Coutière, 1910, and Pachycheles riisei (Stimpson, 1858) are new records for Bahia.