RCAAP Repository

Individuals of Trachemys dorbignyi (Duméril & Bibron, 1835) less than 12 months old are examined for sexual identification through anatomical study of urogenital system. Histological analysis is used to confirm sexual identification. It is concluded that accurate sexual identification is possible in hatchlings using gonadal morphology. Differences between testes and ovaries are clear so histological analysis is necessary for this species only in case of doubts.

The anatomy of Cochlespira elongata, a new species from continental slope of São Paulo coast, Brazil, is described. This analysis shows some interesting characters in the foregut, with rhynchodeal walls muscular and free from the haemocoel and insertion of venom gland in mid region of the esophagus; in the osphradium, with bilobed right filaments; and in the penis, with a complex arrangement of structures in the tip. A complementary description of Cochlespira radiata (Dall, 1889a) from Florida, USA, is also given, for a better comparison between both species.

This work had as objective to compare the communities of Entomobryidae and Isotomidae (Collembola) among no-tillage in three fertility levels, conventional tillage and a natural ecosystem (native grassland). In the no-tillage in low fertility and medium fertility Entomobryidae and Isotomidae had populational picks in the winter and in the summer. In the no-tillage in area of high fertility, there was a populational pick for both families in the summer. In relation to the conventional tillage, Entomobryidae had a populational pick in the winter, and Isotomidae in the winter and in the summer. In the natural ecosystem Entomobryidae presented populational picks in the winter and in the summer and Isotomidae had regular populational fluctuation along the period of the experiment. The final mean density of Entomobryidae was larger in the natural ecosystem, proceeded by the treatments of no-tillage and finally, for the conventional tillage. In relation to Isotomidae, the no-tillage in area of low fertility was superior, coming the conventional tillage soon after, the no-tillage in médium and high fertility, and, finally, the natural ecosystem.

This work had as objective to compare the communities of Sminthuroidea and Onychiuridae (Collembola) among no-tillage in three fertility levels, conventional tillage and a natural ecosystem (native grassland). In the conventional tillage and in the no-tillage in area of medium fertility, the community of Sminthuroidea had regular fluctuation along the period of the experiment, but wtth low densities. The no-tillage in area of high fertility presented a populational pick in the autumn; the no-tillage in area of low fertility, in the spring; and, the natural ecosystem, in the summer. As the final mean density of the population of Sminthuroidea, was observed that the no-tillage in area of low fertility went numerically superior to the others, proceeded by the natural ecosystem, no-tillage in area of high fertility, conventional tillage, and, finally, no-tillage in area of medium fertility. Onychiuridae had three populational picks in the no-tillage in area of low fertility: being a larger in the winter and other two, smaller in the summer and in the autumn. In the no-tillage in area of medium fertility presented only a populational pick in the winter. In the other treatments there was not significantly populational picks. In relation to the final mean density ofthe community of Onychiuridae, the no-tillage plantation in area of low fertility was superior, proceeded by the other treatments of no-tillage, and, in third plan, the natural ecosystem and the conventional tillage.

Cephalella Malloch, 1926, a monotypic Neotropical Lauxaniidae genus, characterized by the presence of long antennae and a prominently convex face, is reviewed. The range of C. fumipennis is amplied.

A list of the Nymphalidae (Heliconiinae) described by Benedicto Raymundo [da Silva]; (Charaxinae) by A. H. Fassl (supplement); (Limenitidinae) by C. Fiedler and (Danainae) e Pieridae (Dismorphinae, Coliadinae) by Romualdo F. D'Almeida (supplement), with the repositories of their types, are presented. Lectotypes are designated for Eueides pavana f. ferruginea Raymundo, 1931; Agrias narcissus var. chrysotaenia Fassl, 1924; Agrias narcissus porphyrionis Fassl, 1921; Agrias narcissus ilustrissimus Fassl, 1921; Lycorea ceres ceres var. acreana D'Almeida, 1939.

Callinectes maracaibonesis Taissoun originally recorded from Venezuela is now confirmed to be present in the northeast region of Brazil. In fact, the species is more common than C. bocourti and possibly due to its close resemblence to the former may have been identified as the latter. Striking colour patterns of the two species which co-exist in the same habitat drew attention of the authors and a careful examination of several specimens showed distinct morphological differences between the two species.

The retina of Metynnis roosevelti Eigenmann, 1915, a very active freshwater fish, was investigated by light and electron microscopy and was found to have a complex neuronal structure that allows rapid responses of visual stimuli. Retina photoreceptors are double cones, single long cones, single short cones and rods. Cone inner segments are arranged as mosaics. The outer nuclear layer contains small nuclei of twin cones, long and wide nuclei of long single cones, spherical large nuclei of short cones, and small dense nuclei of rods. Horizontal, amacrine, bipolar and ganglion neurones are responsible for connections and integration between photoreceptor cells and afferent neurones. The pigmented epithelium comprises a single layer of cylindrical cells each with elongated nuclei, mitochondria at the basal region, and melanin grains that can migrate inside long cell processes, depending on light intensity. In darkness, pigment is concentrated in the basal region of the cells and in daylight it is concentrated in the processes, surrounding and protecting the outer segments of photoreceptors. When exposed experimentally to monochromatic red light, expansion of melanin pigments was provoked at the beginning of light period, followed by their withdrawal after exposure to long wave lengths. No active movements of cones or rods were observed. Considerable renewal of photoreceptor membrane discs occurred after one week in red light, caused by higher level of activation of rods to allow the fish to see in relative darkness. Metynnis roosevelti is a native fish from Brazilian tropical and sub-tropical regions. More recently trials were made to use it in fish cultures in different regions of the countiy. Its capacity to adjust to different photic environments facilitates for rearing in varied environments.

The leukocytes parameters in approximately one-year-old freshwater fish Colossoma macropomum Cuvier, 1818 (tambaqui) kept in an intensive monobreeding system as well as the correlation among these parameters and the biometric data (total weight and standard length) were investigated. The mean value of the white blood cell count (WBC) in the peripheral blood of tambaqui was 2663.3±1288µl and in the differential count, the following means were observed: neutrophils (1566.2±754µl); lymphocytes (973.6±447µl); monocytes (86.7±123µl) and special granulocitic cells (7.8±144µl). The blood parameters studied were positively correlated among one another, but were negatively correlated with the standard length. However, no correlation was with the weigth of the animals was shown. The leukocytes in Colossoma macropomum kept in an intensive monobreeding system were morphologically similar to those of other Brazilian teleosts described in literature.

The borer beetle Hedypathes betulinus, plague of "erva-mate" (Ilex paraguariensis St. Hil., 1822), has been subject of study aiming its biological control. Larvae of this insect digs galleries in the stem and branches of this tree, difficulting its control. Labena fiorii sp.n. was found in branches of this tree, parasitizing larvae of Hedypathes betulinus in Teixeira Soares and in "aroeira" (Schinus sp.) in larvae of Chydarteres striatus (Fabricius, 1787) in Curitiba, Paraná, Brazil. Labena fiorii sp.n., from Paraná (Curitiba; Teixeira Soares) and Santa Catarina (Seara, Nova Teutônia) Brazil, is described.

A new species of Dasineura Rondani, 1840 (Diptera, Cecidomyiidae) which causes galls on Psidium cattleianum Sabine, 1821 is described and illustrated (larva, pupa, male, female). The gall is characterized and some biological notes are given.

Charidotis trifasciata sp.n. from Córdoba, Argentina, is described.

The diet and diel feeding pattern of the skate Raja agassizii were investigated through analysis of stomach contents. A total of 280 stomachs were collected by a series of hauls during a daily cycle in three periods, 8-10 January 1987, 22-24 July and 2-4 December 1988, from the inner continental shelf of the coastal ecosystem of Ubatuba, São Paulo State, Brazil (25º35'S; 45º00'W). According to the results of the stomach fullness and of the number of fresh prey, it is suggested that this species presents continuity in the feeding activity during a day. The stomach contents were mainly composed of crustaceans. Nematodes, polychaetes and fishes also occurred. No changes were observed in dietary composition between day and night.

Five new species of Eucerine bees from the genus Thygater Holmberg, 1884 are described: Thygater (Thygater) anae sp.n., Thygater (Thygater) armandoi sp.n. and Thygater (Thygater) minarum sp.n. from Brazil; Thygater (Thygater) ubirajarai sp.n. and Thygater (Thygater) laevis sp.n. from Venezuela.

The efficiency of insecticides against Sitophilus oryzae (Linnaeus, 1763) (Coleoptera, Curculionidae) and Rhyzopertha dominica (Fabricius, 1792) (Coleoptera, Bostrichidae) was determined exposing them to treated wheat in laboratory. Each plot, which was composed by 1.2 kg of wheat grain, was treated with 5 ml of the concentration/kg of wheat using a propelling air atomizer. Fifteen days after treatment 50 g samples of the grain were taken, from each plot, placed in plastic jars into which 10 adult insects of each species were released. This was repeated every 30 days until 165 days after treatment. The number of dead insects was counted 15 days after each infestation thus the evaluations were made at 30, 60, 90, 120, 150 and 180 days after the insecticide application. Esfenvalerate+fenitrothion+pyperonil butoxide (0,375+7,5+3,0 and 0,5+10,0+4,0 g a.i./t), fenitrothion+esfen-valerate (7,5+0,375 and 10,0+0,375 g a.i./t), fenitrothion+synergised deltamethrin (7,5+0,375 g a.i./t) and fenitrothion (7,5 g a.i./t) were effective against Sitophilus oryzae until 180 days after treatment. Esfenvalerate+fenitrothion+pyperonil butoxide (0,5+10,0+4,0 g a.i./t), fenitrothion+esfenvalerate (7,5+0,375 and 10,0+0,375 g a.i./t), fenitrothion+synergised deltamethrin (7,5+0,375 g a.i./t) were effective against R. dominica until 180 days after treatment. Synergised deltamethrin (0,375 g a.i./t) was effective against S. oryzae until 150 days and against R. dominica until 120 days after treatment. Esfenvalerate (0,5 g a.i./t) was ineffective against S. oryzae and effective until 60 days after treatment against R. dominica. Fenitrothion (7,5 g a.i./t) was ineffective against R. dominica. The use of mixtures of organophosphorus plus pyrethroids were more effective against S. oryzae and R. dominica when compared with these insecticides used alone.

The aim of this work is to describe the reprodutive cycle of the males of L. occipitalis from the coastal sand-dunes of Rio Grande do Sul State, Brazil. It was carried out between April/86 and March/88, at Jardim Atlântico Beach, Tramandaí, Rio Grande do Sul. These lizards showed reprodutive activity between September and December, with a retreat period during January and February. The seasonality of the reprodutive cycle became fully evident by the monthly variation of the testicular mass, showing an inverse relation with the temperature along the year.

Bethylopsis carinatus sp.n., and Epyris chilensis sp.n., from Chile are described and illustrated. Taxonomic data on Chilepyris herbsti Evans, Lytopsenella herbsti (Kieffer), Lytopsenella testaceicornis (Kieffer) and Pseudisobrachium erythrocephalum Evans are included. Male of Lytopsenella herbsti is recorded for the first time to genus and species.

The composition and structure of the edaphic macroarthropod community of these two sites were comparatively studied. The results obtained show that the total densities in the plantation of C. robusta can be higher than in the primary forest. Even though, contrarily to the observed in the forest, this community is characterized by the dominance of some non social groups and by the concentration of most of its individuals in the litter layers. As a consequence, the entire community is more susceptible to seasonal variations in density. Thus, these results emphasize the importance of the leaf litter in providing habitat, food as well as more stable microclimatic conditions for the macroarthropods community. For this reason it is importam to avoid any kind of land management that takes the litter from the soil.

The first official occurrence of the exotic species Clarias gariepinus (Burchell, 1822) in the Rio Paraopeba (São Francisco river basin), the Rio Grande (Paraná river basin), and the Rio Doce (Doce river basin), is reported, with comments on the possible ecological consequences and on the conservation of freshwater fish biodiversity due to non-native species introductions.

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