Life history of the spider Selenops occultus Mello‐Leitão (Araneae,Selenopidae) from Brazil with notes on the natural history of the genus

Selenopids are extremely fast‐moving, dorsoventrally flattened spiders and are among the most secretive of animals. However, they can be locally abundant, providing an opportunity to examine their life and natural histories. Here we report life history data from Selenops occultus which were studied and collected monthly for over a year at an experimental farm of São Paulo State University in Botucatu, Brazil. We compare these data with what we have found in other Selenops species in the Caribbean region. Overall, S. occultus showed considerable seasonality. Males were most common in January and March, whereas females were more common in June and November. Significant differences between the numbers of males collected during the wet and dry seasons indicate that mating may be limited to the wet season. The Caribbean species share similar natural histories to S. occultus, such as little conflict in small areas and overlapping generations throughout the year.     

Microdistribution of juveniles and adults of the mud crab Panopeus americanus (Brachyura,Panopeidae) in a remnant mangrove area in the southwest Atlantic

The distribution and density of a population of the narrowback mud crab Panopeus americanus were evaluated, with emphasis on the different developmental stages (juveniles and adults) and sexes. Specimens were collected in a remnant human‐impacted mangrove at Araçá on the northern coast of São Paulo, Brazil, at two‐month intervals from January through July 2006, using 1 m×1 m sample plots randomly distributed in the intertidal zone. The population was abundant, with a mean density of 14.3±9.3 individuals/m². Larger individuals were more abundant in the upper and middle intertidal zones, whereas smaller crabs were predominant in the lower intertidal and thus remained submerged longer. Males and juveniles were homogeneously distributed. Females preferred regions farther from the waterline. A clustered distribution pattern suggested gregarious behaviour and settling of juveniles in the vicinity of the adults' habitats, in an adaptive process as a function of tidal rhythms.     

A reassessment of neotropical species of Corvospongilla (Porifera: Spongillidae)

This paper expands the known geographic distribution of Corvospongilla seckti Bonetto and Ezcurra de Drago, 1966 to another two Brazilian hydrographic basins, the East Atlantic and São Francisco basins. Simultaneously, it reassesses the status of C. seckti and Corvospongilla volkmeri De Rosa Barbosa, 1988. Re-examination of the holotype of C. volkmeri revealed no remarkable diagnostic features to differentiate it from C. seckti, given our present knowledge on the variability of the latter. Accordingly, C. volkmeri is considered a junior synonym of C. seckti.     

Along‐ and across‐shore components of the spatial distribution of the clam Tivela mactroides (Born, 1778) (Bivalvia,Veneridae)

Beach clam fisheries often provide an alternate income for traditional fishermen, but this activity is highly vulnerable to urbanization of coastal areas. Tivela mactroides is a beach clam commonly harvested in the Caribbean (Venezuela) and on the south‐eastern Brazilian coast. Only localized records on its spatial structure in size and abundance are available to support management of this clam. The present study showed that the spatial distribution in abundance and size of T. mactroides in Caraguatatuba Bay, state of São Paulo, Brazil, has both along‐ and across‐shore (intertidal and subtidal) components. The nature of this distribution should be taken into account in the design of further population or monitoring studies concerning this species. Clam density varied along‐shore, with a tendency towards higher numbers of individuals in the stations near the northern side of river mouths of this bay. Lower densities were related to the occurrence of sea‐stars and sand‐dollars. The intertidal and subtidal across‐shore distribution of clam abundance and size varied between and within areas (southern and northern). The individuals from the southern area were concentrated at intermediate tidal levels (0.2–0.6 m in relation to mean low water), whereas in the northern area the clams were more homogeneously distributed. The uppermost limit of their distribution was 0.8 m (southern) and 0.4 m (northern), and an upwards tendency towards increased size was more evident in the northern area. In the subtidal, abundance and individual size tended to increase from the deepest (4.5 m) to the shallowest (0.5 m) levels only in the southern area. Individual clams in the northern area tended to be smaller and more abundant than in the southern area. The species had an ontogenic distribution: small‐sized individuals were recorded only in the subtidal. Possible causes for these patterns and for the differences between areas (human exploitation, organic pollution, beach morphodynamics, differential recruitment, and adult–larvae interactions) are discussed, and specific studies are suggested to evaluate formally the proposed hypotheses.     

Spatial distribution of the ghost crab Ocypode quadrata in low‐energy tide‐dominated sandy beaches

The spatial distribution of the ghost crab Ocypode quadrata (Crustacea, Brachyura) was described in five low‐energy tide‐dominated sandy beaches in São Sebastião Channel (Grande, Zimbro, Pitangueiras, Cabelo Gordo, and Segredo). On each beach, the zonation study was performed on five random 1?m wide transects sampled from the water line to the vegetation. In general, individuals occurred above 1?m in height in relation to mean low water (MLW) and peaked between 1.5 and 2.0?m. The sandy beaches were then divided into three 1?m wide strips (tidal levels) parallel to the water line and equivalent to medium intertidal, upper intertidal, and subterrestrial fringe to test the effect of beach and tidal level on the abundance and size of O. quadrata. These strips were sampled as a whole using adjacent 1 m² squares. A previous evaluation showed a positive significant relationship between carapace length and burrow diameter, thus supporting crab size estimates from burrow openings. The smallest individuals occurred mainly in the medium intertidal, but were also recorded in the subterrestrial fringe, which was occupied mainly by large‐sized individuals. In general, the individuals were randomly dispersed within the strips and concentrated in the upper intertidal zone on all the sandy beaches. The density of O. quadrata varied among beaches, with a tendency to lower values on areas with very fine and poorly or moderately sorted sediments and on that most used for recreational activities (Grande). Burrow size also varied among beaches, with a tendency of smaller burrows in areas with coarser sand grains and higher tourism. These results indicate that the effect of human impact on density and size of O. quadrata may be confounded by the high environmental heterogeneity of the studied system, which may make it difficult to utilize this species as an indicator of the conservation status of low‐energy tide‐dominated sandy beaches.     

Description and ecology of a new species of sun spider (Arachnida: Solifugae) from the Brazilian Cerrado

A new species of solifuge from São Paulo State, south-eastern Brazil, is described, together with its phenology, habitat use, activity pattern and the effect of fire on the population. Mummucia coaraciandu n. sp. differs from other Mummuciidae in cheliceral dentition and pleurite coloration. Over a one-year period, 649 individuals of M. coaraciandu were captured in 72 pitfall traps distributed in three Cerrado physiognomies: borders of gallery forest (N=53), campo sujo (N=561) and campo cerrado (N=35). The species is diurnal and showed two peaks of surface activity during the year: the highest peak occurred in the cold–dry season (June to July) and the smaller peak in the middle of the warm–wet season (December to February). The number of individuals per trap was negatively correlated with the mean monthly temperature, but showed no correlation with the monthly precipitation. The sex ratio was male-biased (7:1) and the number of males trapped was positively correlated with the number of reproductive females. More individuals were trapped in burned areas when compared with unburned areas 1 month after the fire. This difference between the two areas was not observed 1 month before and 3–4 months after the passage of the fire (when the vegetation had recovered). Mummucia coaraciandu is the second solifuge described from the Brazilian Cerrado and its ecology is very similar to that of Mummucia mauryi from Caatinga vegetation.     

Shell condition and adequacy of three sympatric intertidal hermit crab populations

Shell use in relation to size adequacy and presence of physical damage and encrustation was evaluated and compared among and within three co-existing species of intertidal hermit crab (Clibanarius antillensis, C. sclopetarius and C. vittatus) in the intertidal region of Pernambuco Islet, São Sebastião Channel, south-eastern Brazil. Comparisons of shell utilization patterns among species and sexes were made with respect to physical damage (perforations and breakage in aperture and apex), encrustation by other organisms and shell size adequacy. Two adequacy indices were calculated. The visual adequacy index (VAI) was based on the degree of hermit crab retraction into the shells (1 = crab totally retracted and 6 = shield exposed). The shell adequacy index (SAI) was calculated through a comparison of the weight of the used versus the preferred shell. A relationship was found between VAI and SAI with crabs assigned as VAI = 3 occupying optimal shells (SAI = 1), i.e. crabs that could retract and those that could not retract the whole body into shells were in relatively heavier and lighter shells than the preferred ones, respectively. Shells utilized by the hermit crabs were generally undamaged and highly encrusted (except for C. antillensis) by oysters, barnacles and green algae, features that may reduce the risks of desiccation and predation. The frequent damage to the shell apertures was associated with a high abundance of shell-crushing predators in the studied area. The degree of encrustation as well as the shell adequacy (VAI and SAI) showed intra- and interspecific variation, while the presence of damage differed only among sexes (reproductive classes). In general, the smallest individuals in the populations used relatively heavier shells. Fecundity of the crabs of this assemblage is thought not to be limited by shell use once ovigerous females are occupying optimal shells.     

Reproductive biology of Scinax fuscomarginatus (Anura,Hylidae) in south‐eastern Brazil

The present study describes the reproductive biology of Scinax fuscomarginatus in a remnant of Cerrado in south‐eastern Brazil. Observations were made between September 2002 and March 2004 at Estação Ecológica de Itirapina, State of São Paulo, south‐eastern Brazil. Breeding activities occurred in lentic and temporary bodies of water during the rainy season. Scinax fuscomarginatus exhibited a prolonged breeding pattern and a lek mating system. Males were smaller than females and defended individual calling areas through acoustic and physical interactions. Resident males consistently won encounters, but did not differ in size or mass from intruder males. Satellite behaviour was observed, but no female or amplected pair interception was registered. Scinax fuscomarginatus exhibited low operational sex ratios and the general reproductive mode in which eggs are laid in the water and tadpoles are aquatic. Amplexus was axillary and the eggs were deposited at the bottom of temporary ponds. Details on oocytes, egg masses, and eggs are included.     

Revision of the genus Cylindrommata Tippmann (Insecta: Coleoptera: Cerambycidae)

The monotypic genus Cylindrommata is revised, and three new species are described from Brazil. Cylindrommata aurantia sp. nov. is recorded from the states of Rio de Janeiro and São Paulo, and differs from other species principally by having the prothorax tuberculate at the sides, pronotum subplane and elytra orangish. Cylindrommata lustrata sp. nov. is from Minas Gerais, and has the prothorax without tubercles, rounded at the sides, and elytra short and black with dark-blue reflections. Cylindrommata susanae sp. nov. is from Minas Gerais, Rio de Janeiro, and São Paulo, and has the prothorax without tubercles, parallel at the sides, and elytra yellowish. A key to the species is provided, and all the species are illustrated.     

Responses of pink shrimp Farfantepenaeus brasiliensis (Latreille, 1817) (Penaeoidea) to physico-chemical parameters in a marine protected area: changes in abundance and distribution after 20 years

ABSTRACT

This study analysed the influence of temperature, salinity and sediment texture on the distribution of pink shrimp juveniles (Farfantepenaeus brasiliensis) over a 20-year period. The shrimps were sampled monthly in Fortaleza Bay, north coast of São Paulo, Brazil, in November 1988–October 1989 (period 1) and then 20 years later in November 2008–October 2009 (period 2). In period 1 we captured 80 juveniles whereas in period 2 we captured 226. The abundance and distribution of F. brasiliensis seemed to be modulated by temperature and sediment texture, along with the fishing activity. The management strategies established between the samplings might have been responsible for the higher abundance of juveniles seen during period 2. The strategies included the limitation of fishing effort, regulation of fishing equipment and the establishment of environmental protection areas and temporary fishing ban.     

Abundance and ecologic distribution of the shrimp Rimapenaeus constrictus (Crustacea: Penaeidae) on the northern coast of São Paulo State,Brazil

The abundance and ecologic distribution of the shrimp R. constrictus were compared among three different embayments within the northern coast of São Paulo State (23°S, 45°W); i.e. Mar Virado (MV), Ubatuba (UBA) and Ubatumirim (UBM). Key environmental factors were monitored for a better understanding of the distributional patterns of this species, namely temperature, salinity, depth, organic matter content and texture of sediments. In each bay, six transects were delimited, four parallel to the coastline and the other two in areas adjacent to rocky shores. Monthly samples were taken over a 2-year period (1998 and 1999), using a shrimp fishing boat equipped with double-rig nets. Abundance data were treated separately according to environmental characteristics. A total of 4978 specimens was obtained; 921 at MV, 1948 at UBA and 2109 at UBM. The spatial distribution of R. constrictus differed among bays. Higher abundance values were recorded at areas where silt and clay comprised less than 70% of the sediment. A more diversified sediment at UBM and UBA apparently favours the establishment of this species in the region. Its abundance also followed a seasonal trend, higher during spring and summer when intrusions of cold South Atlantic Coastal Waters (SACW) are frequent, promoting the migration of this shrimp to more sheltered areas. These results suggest that sediment type and temperature are the most important variables affecting the spatial and seasonal distribution of this species.     

Comparative population biology of Uca rapax (Smith, 1870) (Brachyura,Ocypodidae) from two subtropical mangrove habitats on the Brazilian coast

The structure of two populations of the fiddler crab Uca rapax in two subtropical mangrove habitats near Ubatuba, State of São Paulo, Brazil were compared. The size–frequency distribution, sex ratio, and recruitment were evaluated. Sampling was performed monthly from April 2001 to March 2002 in the Itamambuca and Ubatumirim habitats. Crabs were caught manually for 15?min by two collectors during low tide. The carapace width of each crab was measured with a digital caliper, and the sex and ovigerous state were recorded. The median size of the carapace width of males was greater than that of females at both sites (P<0.05). The median size of the crabs from Itamambuca was larger than at Ubatumirim (P<0.05). Only 28 ovigerous females were obtained from both mangroves, which suggested that females might remain in their burrows during the incubation period. The highest recruitment pulse occurred in winter for both populations, probably as a consequence of high reproductive activity during summer. The sex ratio in the size classes showed an anomalous pattern, with a higher frequency of females in the intermediate size classes. This may be related to a greater energy requirement for reproduction in females, thus delaying growth. The variable environmental conditions to which Uca rapax populations are subject appear to act directly or indirectly on the population, causing variations in growth and reproductive processes in the different populations investigated here.     

Egg production of two sympatric species of Hyalella Smith, 1874 (Crustacea,Amphipoda, Dogielinotidae) in aquaculture ponds in southern Brazil

This study tests the hypothesis that sympatric species of Hyalella may show different reproductive strategies that permit their coexistence. Ovigerous females were collected monthly with nets during a 1-year period in two aquaculture trout ponds in Vale das Trutas, São José dos Ausentes County, southern Brazil. In both species there was a decrease in the number of embryos in the brood pouch during embryonic development, and an increase in egg volume. However, the two species differed in the body size of ovigerous females, number of eggs and juveniles per female, brood mortality rate, egg size and hatching size of juveniles. Egg production continued throughout the year, with the highest number of eggs produced during winter and spring by Hyalella pleoacuta, and winter, spring and autumn by Hyalella castroi. These differences in the reproductive traits of species of Hyalella may permit their coexistence in nature.     

Two new species of phytoseiid mites (Acari: Phytoseiidae) from the State of São Paulo,Brazil

Two new species of phytoseiid mites, Amblyseius ica and Typhloseiopsis dorsoreticulatus, from the State of São Paulo, Brazil, are described and illustrated. Amblyseius ica belongs to the americanus species group and dombeyus species subgroup, being the second species of that subgroup. Typhloseiopsis dorsoreticulatus is the first species of the genus Typhloseiopsis recorded outside Central America.     

A new species of Pseudobranchiomma Jones (Polychaeta: Sabellidae) found amongst Brazilian coral,with a redescription of P. punctata (Treadwell, 1906) from Hawaii

A new species of Pseudobranchiomma Jones, 1962 is described from a collection of polychaetes associated with stony coral on the coast of São Paulo State, Brazil. Pseudobranchiomma minima sp. n. differs from the type species P. emersoni Jones and from most other Pseudobranchiomma species in lacking serrations along the outer surface of the crown radioles. Only one other recorded fairly small species, Pseudobranchiomma punctata (Treadwell, 1906, new combination), lacks such serrations and is redescribed here. The two species differ mainly in the configurations of the collars and chaetae. This genus has characters more in common with Bispira than with Branchiomma.     

Reproductive strategies of two sympatric species of Hyalella Smith, 1874 (Amphipoda,Dogielinotidae) in laboratory conditions

This study was performed in order to test theoretical predictions that sympatric species might show different reproductive strategies to facilitate their coexistence. The duration of precopulatory mate‐guarding behaviour, body size of ovigerous females, embryonic and postembryonic development time, fecundity, and viability of the sympatric amphipod species Hyalella pleoacuta and H. castroi were investigated under laboratory conditions (19±1°C and 12 h light/dark photoperiod). Specimens were collected with nets in autumn and spring 2004, and summer and winter 2005 in the Vale das Trutas, São José dos Ausentes County, southern Brazil, and transported to the laboratory. Both species of Hyalella showed similar reproductive strategies, especially in respect to the duration of the precopula, duration of the embryonic period, and fecundity. However, these species differed in body size of ovigerous females, duration of the postembryonic period, viability, and body size of juveniles that remained in the marsupium and those released by females. These differences in the reproductive traits of H. pleoacuta and H. castroi may facilitate their coexistence in nature.     

On taxonomy and hosts of Leptostylum Macquart, 1851 (Diptera: Tachinidae: Blondeliini), with description of a new species and a new host record

Tachinid flies are well known as being parasitoids of arthropods, mostly insects. Because of this, there is great economic interest in the biological control of pests using tachinids. Host records for Tachinidae, however, are still scarce, especially in the Neotropical region. A new species of the Neotropical genus Leptostylum Macquart was reared from Automeris naranja Schaus (Lepidoptera: Saturniidae), a new host record, in Jundiaí, São Paulo, Brazil. Leptostylum oligothrix Gudin and Messas sp. nov. is herein described, including diagnosis and the first illustration of female terminalia for the genus. Additionally, illustrations and remarks on type material of Leptostylum deposited at Museu de Zoologia de São Paulo (MZSP) are made, a taxonomic catalogue of Leptostylum is provided, and a host record is detailed, including a host catalogue for the genus.

www.zoobank.org/urn:lsid:zoobank.org:pub:C54E5F46-B9D5-49CE-A0C9-D260F2896662     

A new genus and species of Sarcoglanidinae (Siluriformes: Trichomycteridae) from southeastern Brazil,with a re-examination of subfamilial phylogeny

Microcambeva barbata, n. gen. et sp., is described from rio São João, Estado do Rio de Janeiro. It is proposed as the sister group of Malacoglanis and Sarcoglanis, on the basis of three characters: pectoral fin longer than the head, pectoral fin rays projecting well beyond the fin membrane, and a forked caudal fin. Monophyly of the Sarcoglanidinae is confirmed by the unique possession of a long lateral process on the premaxilla and a separate anterior ossification on the palatine. A sister group relationship between the Sarcoglanidinae and the Glanapteryginae is supported by four synapomorphies: a posteriorly directed dorsal process on the quadrate, a large dorsal anteriorly directed process on the hyomandibula, vomer reduced and generalized miniaturization. A more inclusive group composed of Sarcoglanidinae, Glanapteryginae, Tridentinae, Vandeliinae and Stegophilinae is considered monophyletic, since they all exhibit a reduced interopercular patch of odontodes, a reduced or absent metapterygoid, reduction in the number of pleural ribs, and lack an elongate process on the parasphenoid.     

Three new species of Benthana Budde-Lund (Isopoda, ‘Philosciidae’) from Brazil

Three new species of Benthana Budde-Lund, 1908 are described from material collected near São 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.