Morphological redescription and morphometry of Aniara sepulchralis (Coleoptera: Cicindelidae) from Northeast Para, Brazil

Aniara sepulchralis specimens sampled at different locations (Belém and Bragantina microregions) show differences in size of some morphological structures such as head width, pronotum width, distance between eyes, pronotum base width, labral length, labral width, and spur of the third pair of legs. These changes may be due to biotic, abiotic, and structural factors peculiar to each environment. Differences in structures and morphological measurements of males and females of Aniara sepulchralis were observed, characterized as sexual dimorphism in relation to their teeth and labral-clypeal suture. Females present apical teeth and rectilinear suture, whereas males present a more rounded shape in both teeth and the labral-clypeal suture. Regarding measurements, females have greater body length, head width, eye distance, pronotum length, pronotum width, labral length, and pronotum base width than males.

Spatial and Temporal Distribution of Leafhoppers (Hemiptera: Cicadellidae) in a Corn Field.

Leafhoppers (Hemiptera: Cicadellidae) are phytophagous insects that transmit diseases and cause damage to this crop. Thus, the main goal of this study was to verify the spatiotemporal behavior of the leafhoppers Tapajosa ocellata (Osborn, 1926), Dechacona missionum (Berg, 1879), and Dalbulus maidis (DeLong, 1923) in a corn field in Igarapé-Açu, northeastern Pará, northern Brazil. An area of 1.0 ha was used for the development of the study. A mango agroecosystem, a pasture, and secondary forest fragment are adjacent to the experimental area. The sampling of leafhoppers occurred during the 2015 and 2016 harvests. For sampling, 10 random plants per plot were analyzed, totaling 1000 plants per sample. In order to verify the occurrence of leafhoppers, all aerial parts of the plants were analyzed visually. The spatiotemporal behavior of leafhoppers and influence of adjacent areas and phenological stages of corn were verified through geostatistics. From the composition of semivariograms, interpolation maps were constructed by kriging. The results showed that, in 2015, there was a higher incidence of D. maidis compared to the following year. In 2016, 352 individuals of T. ocellata and 66 of D. missionum were observed. Regarding the spatial distribution, it was found that the smallest area of influence of T. ocellata, D. missionum, and D. maidis was 0.09, 0.08, and 0.05 ha, respectively. The spatial distribution of leafhoppers showed an aggregate behavior concentrated close to adjacent areas with a predominance of grasses. Population fluctuation demonstrated that the highest incidence of leafhoppers occurs in the vegetative stages of corn.

Spatiotemporal analysis of distribution of pest and predator in corn crops

ABSTRACT Crop pests have negative impacts on yield. This paper proposes a spatiotemporal geostatistical modeling to compare data of adult Syrphidae fly count and corn leaf aphid Rhopalosiphum maidis (Fitch, 1856) colonies in corn crops. The use of a geostatistical model that allows the space-time variation makes the approach more interesting because it is a more complete model. Multiple regression was used to model the trend component for the variable response adult Syrphidae fly count and corn leaf aphid colonies, with the coordinates serving as covariates and the spatiotemporal variations around the deviation are described by a random spacetime residual field. Finally, the prediction map obtained by kriging may be a biological indicator of possible corn leaf aphid colonies in the corn crop. It was possible to verify that the occurrence of the pest provided a significant increase in adult predators and seminatural habitats may favor populations of natural enemies.

Spatiotemporal analysis of distribution of pest and predator in corn crops

Crop pests have negative impacts on yield. This paper proposes a spatiotemporal geostatistical modeling to compare data of adult Syrphidae fly count and corn leaf aphid Rhopalosiphum maidis (Fitch, 1856) colonies in corn crops. The use of a geostatistical model that allows the space-time variation makes the approach more interesting because it is a more complete model. Multiple regression was used to model the trend component for the variable response adult Syrphidae fly count and corn leaf aphid colonies, with the coordinates serving as covariates and the spatiotemporal variations around the deviation are described by a random spacetime residual field. Finally, the prediction map obtained by kriging may be a biological indicator of possible corn leaf aphid colonies in the corn crop. It was possible to verify that the occurrence of the pest provided a significant increase in adult predators and seminatural habitats may favor populations of natural enemies.

Revision of Hypoxys Amyot amp; Serville, 1843 stat. rest. (Heteroptera Pentatomidae).

Hypoxys is one of four subgenera of Edessa (Fabricius, 1787) together with Aceratodes (De Geer, 1773), Dorypleura (Lepeletier Serville, 1825) and Edessa (Fabricius, 1787). This taxon has a very confusing taxonomy due to incorrect use of the names available, imprecise descriptions, and large number of very similar species. To illustrate the confusion, Hypoxys potentially includes a large number of species of Edessa, but actually contains only the type species, according to the most recent catalogue. The name E. quadridens Fabricius, 1803, type species of Hypoxys, was used for more than a century as a label to identify a large group of similar species. In this work we continue revising Edessa elevating Hypoxys to genus based on the following morphological characters: proximal part of costal margin black; evaporatorium with a deep notch on lateral margin; anterior arms of metasternal process acuminate; pygophore longer than wide and subrectangular or barrel-shaped in dorsal view; dorsal rim of pygophore well-projected, almost reaching posterolateral angles and finishing in a small lobe; and posterolateral angles of pygophore not developed. Hypoxys is being divided in four species groups to include 17 species transferred from Edessa. H. quadridens group comprises: Hypoxys quadridens (Fabricius, 1803) (type species), H. boerneri (Breddin, 1904) comb. nov., H. claricolor (Breddin, 1907) comb. nov., H. dolosus (Breddin, 1907) comb. nov., H. eburatulus (Breddin, 1907) comb. nov., H. necopinatus (Breddin, 1907) comb. nov., H. offuscatus (Breddin, 1907) comb. nov. and H. trabeculus (Breddin, 1907) comb. nov. H. triangularis group comprises: H. triangularis (Dallas, 1851) comb. nov. (type species), H. capito (Breddin, 1904) comb. nov. and H. subrastratus (Bergroth, 1891) comb. nov. H. oxyacanthus group comprises: H. oxyacanthus (Breddin, 1904) comb. nov. (type species), H. brachyacanthus (Breddin, 1904) comb. nov., H. infulatus (Breddin, 1904) comb. nov., H. leptacanthus (Breddin, 1904) comb. nov. and H. tragelaphus (Breddin, 1903) comb. nov. H. balteatus group comprises only H. balteatus (Walker, 1868) comb. nov. These groups of species will be useful to organize the new species of Hypoxys that will be described in upcoming papers. Descriptions, measurements, photos of genitalia of both sexes; photos in dorsal and ventral views of the species; and distribution maps are provided. Males of H. capito, H. claricolor, H. eburatulus, H. infulatus, and H. subrastratus are described for the first time. Female of H. necopinatus is described for the first time. Edessa jugalis is considered a junior synonym of H. quadridens; E. rimata a junior synonym of H. offuscatus; E. scabriventris and E. leprosula junior synonyms of H. triangularis; E. pachyacantha a junior synonym of H. tragelaphus; E. orba a junior synonym of E. oxyacanthus. A key to the species of Hypoxys is also provided.