Temporal dynamic of the relationship between the parasitic isopod Aporobopyrus curtatus (Crustacea: Isopoda: Bopyridae) and the anomuran crab Petrolisthes armatus (Crustacea: Decapoda: Porcellanidae) in southern Brazil

The prevalence of the parasite Aporobopyrus curtatus in Petrolisthes armatus from southern Brazil was determined, and the effect the parasite had on host reproduction was evaluated. Of all 775 crabs sampled in Araca region from March 2005 to July 2006, 3.2% presented bopyrid parasites. All the parasitized individuals had one branchial chamber occupied by two mature parasites, with no preference for the right or left chamber. Male and female hosts were infested in equal proportions. Parasitized juveniles, large individuals and ovigerous females were not found in our study. The absence of parasitized ovigerous females seems to be insufficient evidence to support the hypothesis of parasitic castration and would require a histological study to confirm their reproductive death. The percentage of infestation observed in our study (3.1%) is lower than the one found in other studies and it could indicate the existence of factor(s) regulating the density of A. curtatus in the Araca region. At least in this population, the low but constant presence of the bopyrid A. curtatus population did not appear to have a negative effect on the porcellanid population, and parasitized individuals did not play a significant role in the natural history of P. armatus.

Description of a new species of Asymmetrione (Isopoda: Bopyridae: Pseudioninae) infesting the hermit crab Paguristes tomentosus (Anomura: Diogenidae) from Peru, with a key to species and a review of southeastern Pacific bopyrids

A new species of bopyrid isopod is described from a host hermit crab Paguristes tomentosus collected from Pisco, Peru and assigned to the pseudionine isopod genus Asymmetrione Codreanu, Codreanu and Pike, 1965. This is the second species in the genus with less than 20 asymmetry in females, but agrees with all other species in the genus in having the characteristic ""socket"" on the propodus of the female`s pereopods, and in all characters of the males. A key is provided to the 10 species now in Asymmetrione. New records of an Anathelges sp. from Pagurus villosus collected in central Chile are given but additional material is required to determine whether these specimens represent the eastern Pacific A. thompsoni or the western Atlantic A. hyptius. A review of all the bopyrid species known from the western South American coast, with remarks on their taxonomy and biology, is provided.

Vanamea GEN. NOV. FOR Livoneca symmetricaVAN NAME,1925, (CRUSTACEA, ISOPODA, CYMOTHOIDAE) AND A REDESCRIPTION OF THE SPECIES BASED ON SPECIMENS FROM BRAZILIAN PIRANHAS

Studies of the cymothoid isopod Livoneca symmetricaVan Name, 1925, showed that this species has characters that preclude its inclusion in LivonecaLeach, 1818, or in any other known genus. The species is redescribed on the basis of male and female specimens from the mouth cavities of Amazonian piranhas (Serrasalmus spilopleura(Kner) and S. elongatusKner) and Vanameagen. nov. is proposed for it. The new genus is defined as having: a cephalon that is not immersed in pereonite 1; mandibles that are "foot-shaped" and without incisors, pereopods that are long and unequal in size and shape; a pleon that is not immersed in the pereon; and a pleotelson that is inflated anteriorly and medially.

Anphira branchialis GEN. ET SP. NOV. (CRUSTACEA, ISOPODA, CYMOTHOIDAE) A GILL CAVITY PARASITE OF PIRANHAS (Serrasalmus SPP.) IN THE BRAZILIAN AMAZON

Anphira branchialisgen. et sp. nov. (Crustacea, Isopoda, Cymothoidae) is described from the dorsal areas of the gill chambers of three species of piranhas (Serrasalmusspp.). The fishes were caught in rivers near Manaus, Amazonas State and on Maracá island, Federal Territory of Roraima, Brasil. The new genus and species is characterized by having large, flat coxal plates on ail 7 pereonites. These plates usually extend beyond the margins of the following segments and the 7th ones extend nearly to the pleotelson and cover the lateral margins of the pleonites. The mandible of this species is rounded, "foot shaped" and without incisor. The mandibular palp is short and stout. The maxillules have 3 terminal and 2 subterminal spines. The pleopods are simple lamellar structures with rounded tips. Evidence is presented that these parasites feed on gill filaments.

Biologia reprodutiva de Ligia exotica (Crustacea, Isopoda, Ligiidae) em Rio Grande, Rio Grande do Sul, Brasil

Com o objetivo de elucidar alguns aspectos da biologia reprodutiva de Ligia exotica Roux, 1828, duas populações que habitam o Estuário da Lagoa dos Patos (Molhe Oeste da Barra de Rio Grande e Ilha do Leonídeo) foram analisadas. A amostragem foi realizada quinzenalmente entre o verão/2003 e o inverno/2004. Os animais foram coletados manualmente durante uma hora. O período reprodutivo da espécie foi registrado para os meses de outubro a junho. Nenhuma fêmea ovígera foi observada de julho a setembro. No Molhe Oeste da Barra de Rio Grande, 5.376 indivíduos foram capturados (1.494 juvenis, 1.748 machos e 2.134 fêmeas, das quais 245 eram ovígeras). A proporção sexual estimada foi 0,78 (M:F). Para a análise da fecundidade, 178 fêmeas ovígeras com o marsúpio intacto foram analisadas. O comprimento total destas fêmeas variou entre 20,73 a 34,3 mm, e o número de ovos-embriões variaram de 33 a 142. O comprimento médio de primeira maturação sexual das fêmeas foi 24,65 mm e o número médio de ovos-embriões foi 88. Na Ilha do Leonídeo, 5.519 animais foram coletados (510 juvenis, 1.956 machos e 3.053 fêmeas, das quais 129 eram ovígeras). A proporção sexual foi 0,68 (M:F). Pequenas porcentagens de fêmeas ovígeras foram encontradas de setembro a maio, sendo a mais alta porcentagem observada no final de março. Neste local, 101 fêmeas ovígeras foram analisadas, com o comprimento total variando entre 17,62 a 28,61 mm e o número de ovos-embriões entre 25 e 113. O comprimento médio de primeira maturação sexual das fêmeas e o número médio de ovos-embriões foram, respectivamente, 21,43 mm e 73,8.

Nova espécie de Trichorhina (Isopoda, Oniscidea, Plathyarthridae) do Brasil

Trichorhina tatianae sp. nov., encontrada em Araranguá, Morro dos Conventos, Estado de Santa Catarina, é descrita. A nova espécie pode ser facilmente identificada pela expansão lateral do ísquio do pereiópodo 7 do macho. Trichorhina tatianae sp.nov. é conhecida somente da localidade-tipo.

The genus Trichorhina Budde-Lund in Brazil, with description of seven new species (Isopoda, Oniscidea, Platyarthridae)

Seven new species of Trichorhina Budde-Lund, 1908 are described, six from Southeastern Brazil, T. biumbonata sp. nov., T. lenkoi sp. nov., T. myrmecophila sp. nov., T. orensis sp. nov., T. sexdens sp. nov., T. tropidocerata sp. nov., and one from Central Brazil, T. crassisetae sp. nov. An emended diagnosis for the genus and a key to the 19 species recorded from Brazil are provided. Trichorhina acuta Araújo & Buckup, 1994 is recorded to state of Mato Grosso do Sul.

Balloniscus glaber (Crustacea, Isopoda, Balloniscidae), a habitat specialist species in a disturbed area of Brazil

ABSTRACT Balloniscus glaber Araujo & Zardo, 1995 (Balloniscidae), a Neotropical Oniscidea, has been recorded historically in environments with low or no human interference. In one of these areas, it was determined as aK-strategist. Recently, however, this species was documented in a disturbed forest within urban limits. The present work revealed that the population in the urban area has high density, high number of ovigerous females and mancae in the population, a long reproductive period, and early sexual maturity. These results suggest that modified environments may provide favorable conditions and that the species is not negatively affected by human influence.

A Redescription of Riggia paranensis Szidat, 1948 (Isopoda, Cymothoidae) Based on Thirty-two Specimens from Curimatid Fish of Rio de Janeiro, Brazil, with an Emendation of the Genus

Riggia paranensis Szidat, 1948 is redescribed on the basis of 30 female and 2 male specimens collected from the pericardial cavities of the curimatid fish Cyphocarax (= Curimata) gilberti (Quoy & Gaimard). The fishes were caught in the Itabapoana River, State of Rio de Janeiro, southeastern Brazil. The presence of" dwarf" males, as reported by Szidat, was verified. The fusion of the pleonites and pleotelson in adult females was also confirmed. The generic diagnosis was emended to include details of the mouthparts and pleopods

Neotropical woodlice (isopoda) colonizing leaf-litter of pioneer plants in a coal residue disposal environment

The irregular disposal of coal combustion residues has adverse impacts on terrestrial ecosystems. Pioneer plants and soil invertebrates play an important role in the recovery of these areas. The goal of this study was to investigate the colonization patterns of terrestrial isopods (Oniscidea) in leaf litter of three spontaneous pioneer plants (grass - Poaceae, shrub - Euphorbiaceae, tree - Anarcadiaceae) at sites used for fly ash or boiler slag disposal. The experiment consisted of eight blocks (four per disposal site) of 12 litter bags each (four per plant species) that were randomly removed after 6, 35, 70 or 140 days of field exposure. Three isopod species were found in the litter bags: Atlantoscia floridana (van Name, 1940) (Philosciidae; n = 116), Benthana taeniata Araujo & Buckup, 1994 (Philosciidae; n = 817) and Balloniscus sellowii (Brandt, 1833) (Balloniscidae; n = 48). The isopods colonized the three leaf-litter species equally during the exposure period. However, the pattern of leaf-litter colonization by these species suggests a conflict of objectives between high quality food and shelter availability. The occurrence of A. floridana and the abundance and fecundity of B. taeniata were influenced by the residue type, indicating that the isopods have different degrees of tolerance to the characteristics of the studied sites. Considering that terrestrial isopods are abundant detritivores and stimulate the humus-forming processes, it is suggested that they could have an indirect influence on the soil restoration of this area.

Description of a rare isopod crustacean, Arcturella poorei sp. nov. (Isopoda: Valvifera: Arcturidae), from the Atlantic seaboard of Cadiz (Iberian Peninsula)

This paper describes a new species of arcturidean isopod, Arcturella poorei, from the Atlantic seaboard of Cadiz (Spain). A diagnosis and description of the species is presented, and a comparison with other species of the genus from the area.

A new species of Austrofilius (Crustacea, Isopoda, Janiridae) from the Western Mediterranean

A new species of janiridean isopod, Austrofilius mediterraneus sp. nov., from the Columbretes Islands (Castellón de la Plana), Mediterranean coast of the Iberian Peninsula, is described, given it is the first record of the genus in the Northern Hemisphere. It is mainly distinguished from the other two species of the genus by the male pleopod 1, which is wider at the apex and with hooked lateral lobes, curved and nearly surpassing medial lobes. Furthermore, the female operculum shows only four distolateral setae. The rostrum of Austrofilius mediterraneus sp. nov. is extended into single frontolateral tips but is shorter than in A. furcatus Hodgson, 1910.

Post-haemorrhagic anaemia in sea bass, Dicentrarchus labrax (L.), caused by blood feeding of Ceratothoa oestroides (Isopoda: Cymothoidae)

The effects of the fish parasitic isopod, Ceratothoa oestroides (Risso), on haematological parameters of its cage-cultured sea bass host, Dicentrarchus labrax (L.), were studied. Analyses of blood parameters (cell counts, haemoglobin content and haematocrit) were carried out on parasitized and unparasitized sea bass from a fish farm in Turkey. Parasitized fish had significantly lowered erythrocyte counts, haematocrit and haemoglobin values and significantly increased leucocyte counts. Blood feeding by C. oestroides thus produces a post-haemorrhagic anaemia and the fish appear to mount an immune response to the presence of parasites.

A NEW HOST RECORD, PALAEMONETES CARTERI (GORDON, 1935) (DECAPODA, PALAEMONIDAE), FOR TELOTHA HENSELII (VON MARTENS, 1869) (ISOPODA, CYMOTHOIDAE)

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)