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is a freshwater crayfish native to the southern central United States and northern Mexico. In Brazil, it is only present in natural environment in the state of Sao Paulo. Nutritional and reproduct...

Currently Neotroponiscus comprises eight species. In this study, two new species of this genus of terrestrial isopods are described. Neotroponiscus iporangaensis sp. nov. was collected in limestone caves located in Parque Estadual Turistico do Alto Ribeira (PETAR). Neotroponiscus tuberculatus sp. nov. occurs in iron ore caves of the Iron Quadrangle (local name Quadrilatero Ferrifero) and represents the first species of the genus recorded in iron caves. As tourism and mining are common activities in PETAR and in the caves of the Iron Quadrangle, respectively, both species’ occurrence is threatened.http://zoobank.org:pub:45DFEEEC-0590-49E2-8A53-E48F081FB497

Before the present study, the genus Dubioniscus included four species occurring in Central and South Americas. The examination of Dubioniscus delamarei, D. marmoratus and D. negreae allowed us to revise the genus and to move D. goeldii to Calycuoniscus. Moreover, two new species are described, D. depressus n. sp. from the state of Sao Paulo, and D. elongatus n. sp. from the state of Rio de Janeiro, Brazil.http://zoobank.org/urn:lsid:zoobank.org:pub:1D2B9F44-96EE-48A6-A8DE-D24F190F9AF3.

Two new species of Benthana Budde-Lund, 1908 are described from material collected in the states of Rio de Janeiro and Parana, Brazil. Benthana schmalfussi n. sp. is distinguished by the shape of the male pleopod 1 exopod, whereas Benthana guayanas n. sp. is distinguished by the noduli laterales d/c coordinates and shape of the male pleopod 1 exopod. A new method is given for defining the shape of the outer distal margin of the male pleopod 1 exopod. http://zoobank.org/urn:lsid:zoobank.org:pub:A79EDB3B-F7AC-47A3-ADD8-DA00FFAD69CB

Terrestrial isopods undergo direct development in which the animals molt to juvenile stages after the manca stages in which the sex cannot be recognized. The first three juvenile stages of Benthana cairensis are described with emphasis on the male secondary sexual characters. The ontogeny of the genital papilla, pleopods 1 and 2 and pereiopods were followed. At the Juvenile I stage, males are characterized by a slightly developed papilla, although dimorphism of the pleopod 1 exopod and pereiopods is still not evident at this stage. In Juvenile II individuals, the sub-apical protrusion of the pleopod 1 exopod begins to appear, and it is more evident in Juvenile III. The complete formation of this protrusion is only seen when males reach a cephalothorax width of approximately 1.0 mm; dimorphism of the setation of the four pairs of pereiopods begins later and is evident when males reach approximately 1.04 mm CW.

To observe the behaviour of cymothoid isopods during the infestation process, 30 experiments in aquaria were carried out, using the fish Gymnogeophagus gymnogenys (Hensel, 1870) and Jenynsia multidentata (Jenyns, 1842) as hosts, and Artystone trysibia Schioedte, 1866 as the parasite. All the specimens were collected from Guaiba Lake in Porto Alegre, Rio Grande do Sul. We recorded and analysed the behavioural acts of the parasites and hosts from the moment of encounter to the infestation, which was considered to be completed when the parasite had inserted itself into the fish's body. The behavioural acts are shown as a flow diagram, including the frequencies of occurrence of each act. Positive infestation occurred in 60% of the experiments. No relationship was observed between the sizes of the parasite and host, and the success of the infestation.

The enigmatic philosciid isopod species Benthanoscia longicaudata Lemos de Castro, 1958 was re‐examined using part of the type series, with reference to morphological characters, re‐evaluated for their phylogenetic information content. B. longicaudata is considered to be merely a rather derived member of the genus Benthana Budde‐Lund, 1908, which is common in eastern Brazil. Benthanoscia is retained as a subgenus of Benthana and two other species are also assigned to the subgenus: Benthana morerai Lemos de Castro, 1958 and Benthana sulcata Lemos de Castro, 1958. Redescriptions of B. longicaudata and Benthana taeniata Araujo & Buckup, 1994 are also given.

Summary The postmarsupial development of Atlantoscia floridana (van Name, 1940) was studied, with emphasis on the sexual differentiation and maturity. Samples were obtained in the Reserva Biologica do Lami, Porto Alegre, RS, Brazil, during 2000 and 2002. Collected animals were reared in the laboratory under temperatures of about 20±1°C and observed daily. Animals preserved in 70% ethanol were used to analyze sexual maturity. Growth was monitored as each animal moulted for evidence of sexual differentiation. The development of the male genitalia and the female genital pore was described across the different juvenile stages. Female sexual maturity was estimated to occur at a minimum size of 1.04 mm cephalothorax width. Male sexual maturity was estimated from the morphometric relationship between cephalothorax width and length of the genital papilla and indicated the puberal moult to occur at a minimum size of 0.77 mm cephalothorax width. Identification of the size at which sexual maturity occurs allows reco...

In this paper we describe the postmarsupial development of the manca stages of Atlantoscia floridana (van Name, 1940). Ovigerous females were collected in Reserva Biologica do Lami, Porto Alegre, RS, Brazil and separately reared in small containers at 20°C (±1°C). After birth each newborn (manca I) was reared separately in order to observe the subsequent moults. In a period of about 12 h the animals underwent the first moult. The manca II stage lasts 9.16±1.57 days while manca III takes up a period of 9.96±1.05 days. Growth was observed through measurements of cephalothorax width. The three manca stages are described, illustrated and compared with the adults. The main distinguishing characteristics among mancas I, II and III are presented as well as the b/c and d/c co-ordinates of the noduli laterales.

Three new species of Benthana Budde-Lund, 1908 are described from material collected near Sao Fancisco de Paula, a town in the north-east of the southernmost Brazilian State, Rio Grande do Sul (RS). The new species are: Benthana serrana sp. nov., Benthana trinodulata sp. nov. and Benthana araucariana sp. nov. (from Araucaria Forest). The presence of more than one nodulus lateralis on coxal plate VII, a characteristic not previously known in the genus, is reported. New occurrences of B. picta (Brand, 1833) and B. taeniata (Araujo and Buckup, 1994) are also recorded. A method is given for defining the shape of the exopod of pleopod 1 of the male based on morphometry.