A species-level association in Pheidole Westwood (Hymenoptera: Formicidae) ants with a parasitoid wasp of the genus Orasema Cameron (Hymenoptera: Eucharitidae) in Brazil

Abstract Eucharitid wasps are exclusive parasitoids of ants and certain groups of eucharitids have specific associations with their hosts. This type of specificity is widely documented in more inclusive groups (subfamilies and/or genus-groups). However, we do not know if this specificity occurs in less inclusive groups (such as species or populations) or if it is more strongly influenced by local and/or regional environmental constraints. We provide a new association record between Pheidole gibba Mayr, 1887 and Orasema chunpi Burks, Heraty & Dominguez, 2018, while expanding their known distribution to the Brazilian state of Bahia.

Hunting for Wasps In-between: the Use of the Winkler Extractor to Sample Leaf Litter Hymenoptera.

Soil ecosystems are considered biodiversity hotspots. Most of terrestrial organisms depend almost exclusively on soils at least during some part of their life cycle. Although there is an intensive effort to understand the dynamics involving communities of soil animals, most groups are unappreciated in faunal inventories, such as some parasitic Hymenoptera with soil or litter hosts (SLH Hymenoptera), which are considered one of the largest and most diverse groups of soil- or litter-dwelling animals. Contrasting with flight interception traps, techniques that sample soil and litter specimens normally present low costs and easy transportation, being easily replicated within a site. Among them, the Winkler extractor is a useful technique to sample cryptic species associated with leaf litter. The aim of the present work was to describe the SLH Hymenoptera fauna collected in a pool of samples, using a technique to sample leaf litter arthropods. In this work, we report a total of 600 specimens belonging to Hymenoptera (excluding ants), belonging to 15 families distributed within 24 subfamilies, in samples of leaf litter obtained using the Winkler extractor. We observed that this technique is promising for sampling SLH Hymenoptera and should be considered as a complement for inventories of the Hymenoptera fauna.

Further Ergatoid Gyne Records in the Ant Tribe Dacetini (Formicidae: Myrmicinae).

Variants of gynes and workers occur in a substantial number of ant species; however, dacetine ergatoid gynes have been recorded just once in the literature thus far. In the present paper, we provide abridged descriptions of five ergatoid female reproductives in five species of Neotropical dacetines belonging to two genera: Acanthognathus brevicornis Smith, Acanthognathus ocellatus Mayr, Acanthognathus rudis Brown & Kempf, Strumigenys cosmostela Kempf, and Strumigenys hindenburgi Forel. We also compare the ergatoids with conspecific gynes and workers.