PREDATION OF COTTON LEAFWORM 1ST INSTAR LARVAE, ALABAMA-ARGILLACEA [LEP, NOCTUIDAE]

Natural predation first instar larvae of the cotton leafworm (CLW) A. argillacea was studied in cotton fields in Jaboticabal, São Paulo State, Brazil, during 1986. The presence of naturally occurring arthropod predators showed a first instar larvae predation rate of 78.6 and 88.9% after 24 h and 48 h of exposure, respectively. A predator prey ratio of 1 : 1 (1 CLW key predator per 1 prey/plant) maintained a level of no more than 1 CLW small larvae per plant. The most evident arthropod predators in the studied fields were: beetles (Coleoptera: Coccinellidae), ants Pheidole sp. and Conomyrma sp.; Dermaptera Doru lineare (Eschs); Hemiptera Geocoris sp., and Orius insidiosus Say; and the spiders Theridion volubile, Chrysso pulcherrima, Misumenops sp., Chiracanthium sp., and Oxyopes salticus Hentz.

Winter aggregations, colony cycle, and seasonal phenotypic change in the paper wasp Polistes versicolor in subtropical Brazil

Social wasps from temperate zones have clear annual colony cycles, and the young queens hibernate during winter. In the subtropics, the only previously reported evidence for the existence of hibernation is the facultative winter aggregations of females during harsh climate conditions. As in temperate-zone species analyzed so far, we show in this study that in the paper wasp, Polistes versicolor, a subtropical species, body size increases as an unfavorable season approaches. Our morphological studies indicate that larger females come from winter aggregations-that is, they are new queens. Multivariate analyses indicate that size is the only variable analyzed that shows a relationship to the differences. Given the absence of a harsh climate, we suggest that the occurrence of winter aggregations in tropical P. versicolor functions to allow some females to wait for better environmental conditions to start a new nest, rather than all being obliged to start a new nest as soon as they emerge.

Comparative analysis of drilling frequencies in recent brachiopod-mollusk associations from the Southern Brazilian Shelf

Over 14,000 specimens-5,204 brachiopods, 9,137 bivalves, and 178 gastropods-acquired from 30 collecting stations (0 to 45 m depth) in the Ubatuba and Picinguaba bays, southern Brazil, were compared for drilling frequencies. Beveled (countersunk) circular-to-subcircular borings (Oichnus-like drill holes) were found in diverse bivalves but also in the rhynchonelliform brachiopod Bouchardia rosea-a small, semi-infaunal to epifaunal, free-lying species that dominates the brachiopod fauna of the southern Brazilian shelf. Drill holes in bivalve mollusks and brachiopods are comparable in their morphology, average diameter, and diameter range, indicating attacks by a single type of drilling organism. Drill holes in brachiopods were rare (0.4%) and found only at five sampling sites. Drillings in bivalves were over 10 times as frequent as in brachiopods, but the average drilling frequency was still low (5.6%) compared to typical boring frequencies of Cenozoic mollusks. Some common bivalve species, however, were drilled at frequencies up to 50 times higher than those observed for shells of B. rosea from the same samples. Due to scarcity of drilled brachiopods, it is not possible to evaluate if the driller displayed a nonrandom (stereotyped) site, size, or valve preference. Drilled brachiopods may record (1) naticid or muricid predation, (2) predation by other drillers, (3) parasitic drillings, and (4) mistaken or opportunistic attacks. Low drilling frequency in brachiopods is consistent with recent reports on ancient and modern examples. The scarcity of drilling in brachiopods, coupled with much higher drilling frequencies observed in sympatric bivalves, suggests that drilling in brachiopods may have been due to facultative or erroneous attacks. The drilling frequencies observed here for the brachiopod-bivalve assemblages are remarkably similar to those reported for Permian brachiopod-bivalves associations. This report adds to the growing evidence for an intriguing macroecological stasis: multiple meta-analytical surveys of present-day and fossil rhynchonelliform brachiopods conducted in recent years also point to persistent scarcity and low intensity of biotic interactions between brachiopods and drilling organisms throughout their evolutionary history.

Oviposition pattern and within-season spatial and temporal variation of pre-dispersal seed predation in a population of Mimosa bimucronata trees

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Increased corticosterone levels in mice subjected to the rat exposure test

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

ANTI-HERBIVORE PROTECTION BY MUTUALISTIC SPIDERS and THE ROLE of PLANT GLANDULAR TRICHOMES

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

The role of spatial and temporal descriptors for neotropical tadpole communities in southern Brazil

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

A new synonym, a new male description and new geographical records for three Ceraeochrysa species (Neuroptera: Chrysopidae)

Ceraeochrysa Adams is the largest genus in Chrysopini with 62 valid species distributed in the New World. The taxonomy of this group is complex and largely based on male genitalic characters. There are still serious complications, especially with the species that have been described solely from female specimens. The male of C. montoyana (Navas, 1913), unknown previously, is herein described for the first time, and compared with its closest relative, C. claveri (Navas, 1911). Ceraeochrysa acutipuppis Adams & Penny, 1985 is designated as a junior synonym of C. fairchildi (Banks, 1946) based on the evidence that both species share external morphological features uncommon in other species of the genus. The species C. claveri, C. fairchildi and C. montoyana are recorded from Venezuela for the first time. External morphology and genitalia of these insects are described and illustrated.

Direct and indirect top-down effects of previous contact with an enemy on the feeding behavior of blowfly larvae

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Predation potential and biology of Protogamasellopsis posnaniensis Wisniewski & Hirschmann (Acari: Rhodacaridae)

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

The ecological causes of individual specialisation

University of Tennessee, KnoxvilleNational Science Foundation (NSF)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Food-web composition affects cross-ecosystem interactions and subsidies

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Dinâmica espaço-temporal de taxocenoses de crisopídeos (Neuroptera: Chrysopidae) em ecossistemas naturais

In order to study the interactions of green lacewings toxocenosis on natural ecossystems, samplings were carried out in the Parque Ecologic Quedas do Rio Bonito, located in Lavras, Alto Rio Grande region, South of Minas Gerais, Brazil. The species inventory was accomplished in two vegetation types: semi-evergreen forest and open field formations, including areas of montane grassland, rocky montane grassland and "cerrado". Insects were captured with a butterfly net during 2h, walking through each vegetation formation. Sampling resulted in 1,948 specimens belonging to 30 species, of which 14 were Chrysopini and 16 Leucochrysini. Representatives of these tribes were observed both in forest and in open field formations. Species of the genera Ceraeochrysa, Chrysoperla, Chrysopodes, Plesiochrysa and Leucochrysa were found in forests and in open field formations, except for Plesiochrysa. The highest richness and diversity of species were observed in the forest. The similarity index among the communities of green lacewings in the studied areas was 27%.

Relationship between predation by Podisus nigrispinus and developmental phase and density of its prey, Plutella xylostella

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

A new genus of Neotropical Chrysopini (Neuroptera: Chrysopidae)

Titanochrysa Sosa & Freitas is a new genus of Neotropical Chrysopini (Chrysopidae: Chrysopinae) recorded from Costa Rica, Venezuela and Brazil. Titanochrysa gen. nov. shares several external and genitalic characters with Ceraeochrysa Adams, 1982; Chrysopodes Navas, 1913; Cryptochrysa Freitas & Penny, 2000; Parachrysopiella Brooks & Barnard, 1990 and Ungla Navas 1914. It may be distinguished from those genera by its very long sternite 8+9, sternites 2-8 usually with microtholi, male genitalia with the dorsal surface of the arcessus striated, gonosaccus well-developed, bearing elongate gonosetae and microsetae, and a spoon-like gonapsis. Herein, Titanochrysa circumfusa (Burmeister, 1939) [= Chrysopodes circumfusa (Burmeister)] comb. nov. and Titanochrysa pseudovaricosa (Penny) [= Ceraeochrysa pseudovaricosa Penny, 1998] comb. nov. were identified; Titanochrysa ferreirai Sosa & Freitas sp. nov. and Titanochrysa trespuntensis Sosa & Freitas sp. nov. were described. The external morphology, and male and female genitalia of all these species are described. Titanochrysa circumfusa (Burmeister, 1939) comb. nov. is recorded for the first time from Venezuela.