Alimentação de quatro espécies de Leporinus (Characiformes, Anostomidae) durante a formação de um reservatório no sudeste do Brasil

The study reports the changes ocurred in feeding ecology of fish species during a tropical river reservoir formation. It was analysed the stomachal contents of 399 individuals belonging to four species of genus Leporinus (L. elongatus Valenciennes, 1849, n=157; L.friderici (Bloch, 1794), n=87; L. octofasciatus Steindachner, 1917, n=107; L.amblyrhynchus Garavello & Britski, 1987, n=48) during formation of Nova Ponte reservoir, State of Minas Gerais, Brazil, in 1993 and 1994. Specimens were separated by sampling period, according with the rate of filling of the reservoir, and standard lenght classes. The species had included in diet vegetal and animal items of autochtone and alochtone origin in several proportions. L. amblyrhynchus fed on basically dipterans in all the sampling periods and length classes. L. elongatus had presented a diverse diet, with predominance of dipterans and vegetal items, and changed the consumed items proportions along the sampling periods and between lenght classes. L. friderici diet was composed mainly by terrestrial insects during the rapid filling period, that were later substituted by fishes and vegetal items. Ontogenetic trophic changes were observed in this species. L. octofasciatus presented a well characterized herbivorous diet, without trophic ontogeny, but with a opportunistic character. Just three pair-species, L. amblyrhynchus-L. elongatus, L. friderici-L. octofasciatus and L. elongatus-L. octofasciatus, have presented some high value of trophic overlap in at least one sampling period. In spite of the fishes of the genus Leporinus being classified like omnivorous in a general way, the differences found between diets of these four species suggest that there is structuration of trophic niches in the reservoir.

Miridae (Heteroptera) fitófagos e predadores de Minas Gerais, Brasil, com ênfase em espécies com potencial econômico

A total of 296 species of Miridae belonging to 17 tribes were recorded from State of Minas Gerais, Brazil. New host plant records include 141 species of 43 orders and 69 families. Of this total, 98.5% of plants have some agricultural, pharmacological or ornamental importance; 29 orders and families of host plants have two or more mirid species.

Espécies novas e chave para as espécies de Callia (Coleoptera, Cerambycidae)

New species described: Callia marginata from Peru, C. punctata from Colombia, C. annulata from Ecuador, C. tristis from Bolivia, C. paraguaya from Paraguay; from Brazil: C. divisa and C. tomentosa (Mato Grosso), and C. lissonota (Rondônia). A key to the species of Callia is added.

Notas sobre Pseudevoplitus (Heteroptera, Pentatomidae) e descrição de duas espécies novas

Two new species of the Neotropical genus Pseudevoplitus Ruckes,1958 are described, P. amazonicus Grazia & Greve, sp. nov. and P. roraimensis Grazia & Greve, sp. nov. both from the Brazilian Amazonia, with emphasis on genital characters. Additions to the generic description and a new key to the species are presented.

Estolomimus (Coleoptera, Cerambycidae, Desmiphorini): novas espécies e chave

New species described from Brazil: Estolomimus maculatus (Minas Gerais and São Paulo), E. transversus (Espírito Santo), E. lichenophorus (São Paulo), and from Bolivia: E. abjunctus (Beni). A key to the species is added.

Novas espécies de Trichomyia (Diptera, Psychodidae) da Mata Atlântica da Bahia, nordeste do Brasil

Six new species of Trichomyia from Atlantic rain forest of Bahia, northeastern Brazil, are described: T. itabunensis, T. onorei, T. queirozi, T. silvatica, T. sulbaianensis and T. teimosensis. The first two have palpi with four segments, similar to the other Neotropical species. The other four species have palpi with three segments, similar to other species with wide world distribution.

Descrição de duas espécies novas de Opopaea do sul do Brasil (Oonopidae, Araneae)

Two new species, Opopaea viamao and O. ita, are described from the states of Rio Grande do Sul and Santa Catarina, Brazil, respectively. Both species present reduction or loss of posterior median eyes, a possible synapomorphic caracter.

Revisão taxonômica e relações filogenéticas das espécies de Roeboides grupo-microlepis (Ostariophysi, Characiformes, Characidae)

The Roeboides microlepis species-group is revised. Four species are recognized: R. myersii Gill, 1870 from the Amazon basin, R. microlepis (Reinhardt, 1851) from river Paraguay, middle and lower river Paraná, R. araguaito sp. nov. from the river Orinoco basin, and R. margareteae sp. nov. known only from Rio Parnaíba and Pindaré-Mearim, northeastern Brazil. The type-locality of R. microlepis is restricted to river Paraguay; R. bonariensis (Steindachner, 1879) is considered a synonym of R. microlepis. The phylogenetic analysis indicates that R. myersii and R. araguaito are most parsimoniously related and may be a sister group. These two species are here considered as sister group of the monophyletic lineage which includes R. microlepis and R. margareteae. A key to the microlepis species-group genus Roeboides is given.

Duas espécies novas de Lophoblatta (Blattaria, Blattelidae) do Brasil e descrição da genitália de cinco espécies conhecidas

New species described: Lophoblatta bromelicola and L. tingua both from Rio de Janeiro, Brazil. The male genitalia of five other species are illustrated and described. New records are given: L. petropolitana Rocha e Silva & Vasconcelos, 1987 to Espírito Santo and L. speerae Rocha e Silva-Albuquerque & Gurney, 1963 to Pernambuco, Goiás and Espírito Santo, Brazil. The genus is divided in four groups according as the male genitalia characters.

Espécies novas de Otiothops e Fernandezina do norte do Brasil (Araneae, Palpimanidae)

Otiothops lajeado sp. nov. and Fernandezina saira sp. nov., respectively from the states of Tocantins and Amazonas, Brazil, are described.

Dieta de espécies de Anostomidae (Teleostei, Characiformes) na área de influência do reservatório de Manso, Mato Grosso, Brasil

The diet of four species of Anostomidae (Leporinus friderici Bloch, 1794, L. striatus Kner, 1858, L. elongatus Valenciennes, 1849 and Leporinus sp.) were investigated in the Manso Reservoir, Mato Grosso State, Brazil. Fish were sampled in three sites: upriver, in the main body of the reservoir, and below the dam. Were analized 276 stomachs. The diet was evaluated using the frequency of ocorrence and volumetric methods. Leporinus friderici showed tendency to herbivory, mainly in the upriver site. In the reservoir and below the dam, it consumed large quantities of fish; Isoptera only in the reservoir. Leporinus striatus and L. elongatus have similar diets, consuming Chironomidae larvae (Diptera), whereas Leporinus sp. was more generalist, feeding similar proportions of vegetable, detritus and insect (Chironomidae and Ephemeroptera). The mouths of the species have different positions: terminal in L. friderici, subterminal in L. elongatus and intermediate in L. striatus and Leporinus sp. The diet overlap values were low, except for L. friderici and Leporinus sp. (0.7) in the upriver, and L. striatus and L. elongatus (0.6) below the dam.

Novas espécies do gênero Anomiopus, grupo smaragdinus (Coleoptera, Scarabaeidae)

Seven new species of Anomiopus Westwood, 1842 are added to smaragdinus group: from Brazil, A. caputipilus (Goiás), A. impartectus (São Paulo), A. paraensis (Pará), A. preissae (Minas Gerais, Espírito Santo, Rio de Janeiro), A. quadridentatus (Bahia) and A. soledari (Goiás e Distrito Federal); from Argentina, A. similis (Misiones). A key and illustrations of the species are added.

Abundância e flutuação populacional das espécies de Chrysomya (Diptera, Calliphoridae) em Pelotas, Rio Grande do Sul, Brasil

To estimate the populational fluctuation of Chrysomya Robineau-Desvoidy, 1830 species and the relation of populational abundance around, six wind oriented trap (WOT) were placed in three distinct ecological areas (urban, rural and wild) in Pelotas, Rio Grande do Sul, Brazil, from February/1993 to January/1995. The flies were weekly collected. Captured species were Chrysomya albiceps Wiedmann, 1819, C. megacephala Fabricius, 1794 and C. putoria Wiedmann, 1830 with respective abundance of 64.5%, 19.7% and 0.9%, representing a total of 85.0% of 409,920 specimens of Calliphoridae. The three species demonstrated similarity in the populational fluctuation, except in the abundance. The populational peak ocurred in autum when the temperature decreases. In the months of July to November no fly was collected, recomposing the population in December, when the temperature surpassed 20ºC.

Sinopse do gênero Cobelura (Coleoptera, Cerambycidae, Lamiinae, Acanthocinini), com descrição de três espécies novas

Eight species are considered for the genus Cobelura Erichson, 1847, three described herein: C. stockwelli sp. nov., from Panamá (Canal Zone, Darien), C. wappesi sp. nov., from Ecuador (Pichincha) and C. howdenorum sp. nov., from Colombia (Norte de Santander). The treatment of each new species includes information on its geographical distribution, photographs and a comparison with its most similar congenerics. A key to species of Cobelura is presented.

Exigências térmicas para o desenvolvimento de Palmistichus elaeisis (Hymenoptera, Eulophidae) em pupas de cinco espécies de lepidópteros

The thermal requirements of Palmistichus elaeisis Delvare & LaSalle, 1993 were determined by rearing this pupal parasitoid in the following lepidopteran hosts: Diatraea saccharalis (Fabricius, 1794) (Crambidae), Anticarsia gemmatalis (Hübner, 1818), Heliothis virescens (Fabricius, 1777), Spodoptera frugiperda (J.E. Smith, 1797) (Noctuidae) and Thyrinteina arnobia (Stoll, 1782) (Geometridae). The experiment was set in laboratory conditions (temperatures between 18ºC and 30ºC, RH=70 ± 10% and 14-hour photoperiod). The life cycle (egg-adult) ranged from 40.4 ± 0.63 days (18ºC, H. virescens) to 18.1 ± 0.13 days (28ºC, D. saccharalis). The thermal constant of the egg-adult period ranged from 353.1 (D. saccharalis) to 407.7 degree-days (S. frugiperda). The lowest thermal threshold ranged from 5.0ºC (A. gemmatalis) to 7.5ºC (D. saccharalis). At 30ºC, all prepupae died. These results suggest that P. elaeisis can be reared in laboratory on all the hosts tested.