RESUMO

Parasitoid wasps are known to be among the most abundant and species-rich on Earth and thus considered an ecologically important group of arthropods. Braconid wasps play a key role in regulating the populations of Lepidoptera, Coleoptera, and Diptera. However, the biology and taxonomy of numerous parasitoid species remain poorly known. In Mexico, only 17 species of the subfamily Cheloninae have been described. A new species of Pseudophanerotoma Zettel, 1990 (Hymenoptera, Braconidae), P.huichol sp. nov., is described from Nayarit, Mexico. The tortricid moth Cryptaspasmaperseana Gilligan & Brown, 2011 is reported as the host of this parasitoid wasp. Detailed taxonomic and barcoding information are provided.

RESUMO

The family Scoliidae is represented by approximately 560 species worldwide. Of these, 64 species are known to occur in the New World. The greatest diversity of these wasps is concentrated in the Pantropical region. However, both the biology and the taxonomy of Scoliidae has remained understudied over the last six decades in the Americas. Taxonomic keys for the New World species are limited to certain regions of North and South America, showing ambiguous descriptions and unillustrated specimens. This situation has largely restricted aspects such as the species richness, ecology, and thus conservation status of these wasps, especially in Mexico, where there are no taxonomic revisions. In this work, the Scoliidae species from Mexico were revised from 12 entomological collections to update and homologize the list of species. In total, we examined 747 specimens from 23 morphospecies and 9 genera. The diagnosis of each species is presented, including their distribution, and a species checklist is provided. Moreover, the first taxonomic key for the Mexican species is presented. Stygocampsomeris servillei Guérin is a new record for the country. Also, two new Nearctic and four Neotropical records are added. The occurrence records are now expanded to 30 Mexican states. Most species (41.6%) occur in both Nearctic and Neotropical regions. The species Scolia fuscipennis Bartlett is still known from a single sex. This work is the first attempt towards the taxonomy and biogeography of the Mexican Scoliidae; thus, it could be an important baseline for faunistic, ecological, and conservation purposes. Overall, the family Scoliidae has been overlooked and poorly represented in Mexican collections. The specimens were scarce and frequently in bad condition, and none of them include biological or ecological attributes. Systematic sampling and appropriate curation of specimens would help to conduct future revisions, as well as the possible integration of barcoding information allowing integrative taxonomic approaches.

Assuntos

RESUMO

Species within the same trophic level show different strategies to avoid competition. Among these mechanisms, differences in body size, spatio-temporal segregation, and diet preference often leads to a niche partitioning. Nonetheless, little attention on coexisting predatory insects and their network interactions has been paid. In this study, we analyzed the strategies to avoid competition among three sympatric mud-daubing wasps of the genus Trypoxylon (Hymenoptera: Crabronidae) in oases and their surrounding xeric area from the Baja California peninsula, Mexico. We compared the prey richness, composition and proportion of spider guilds that were captured by the wasps. We tested whether the differences in wasp body size explained the niche breadth, niche overlap and the size of spider prey. We assessed the spider-wasp interactions through a network analysis. With the use of trap-nests, we collected 52 spider species captured by the wasps. Both the guild and species composition of preyed spiders was different between the three wasp species. Differential proportions in the capture of spider guilds and a little diet overlap were found among the wasp species. We found that the wasp body size was positively correlated with prey size, but it was not a proxy of niche breadth. Moreover, the largest wasp species was able to nest in both mesic and xeric habitats, while the two smaller species were restricted to the oases. This study reveals that the diversity of spiders in oases of Baja California peninsula is crucial to maintain highly specialized oasis-dependent wasp species. The niche partitioning between mud-daubing wasps can be shaped by their inherent body size limitations and hunting strategies through foraging specialization for specific spider guilds. Food selection and slight differences in body size reduce competition and allow the coexistence of sympatric wasps. Our study is the first approach exploring the interaction networks between mud-daubing wasps and their spider preys, highlighting new insights into the morphological and ecological factors that shape antagonistic interactions, and allow the coexistence of predators in deserts.

Assuntos