DNA barcoding is a popular tool for species identification of insect samples, with important applications for plant protection. However, Barcode of Life Database queries related to tachinid samples can produce ambiguous results due to contradictory species assignments. Therefore, we applied Bayesian phylogenetic inference to 811 Tachina Meigen, 1803 COI-5P sequences containing all contradictory species assignments of Tachina Barcode Index Numbers. Based on phylogenetic assignment, the assemble species by automatic partitioning (ASAP) analysis, the MonoPhy test and analyses of genetic divergence, we identified 805 sequences representing species of the Tachina genus, whereas six sequences were incorrectly assigned to Tachina. The dataset contained 21 described species and at least seven unidentified species. Additionally, we found that the described species Tachina marklini Zetterstedt, 1838, includes two cryptic species based on ASAP partitioning of sequences, phylogenetic inference and geographical metadata. Furthermore, we harmonized conflicting subgeneric classifications of the Palearctic and Nearctic by employing different subgenera assignments from both partitions. We aimed at monophyletic subgenera partitions. We largely confirmed the validity of the Palearctic Tachina subgenera and Nowickia as a subgenus of Tachina. However, Palearctic Nowickia species formerly allocated to the outdated genus Fabriciella appeared to constitute one monophyletic group with the subgenus Rhachogaster. We conclude that this set of bioinformatics tools is suitable for curating COI-5P-based DNA barcode libraries. Although, curation is limited due to possible species introgression, horizontal gene transfer, incomplete lineage sorting and human errors the resulting dataset enabled the revision of subgenera concepts and the unambiguous cryptic species detection.

The study of social parasitism faces numerous challenges arising from the intricate and intranidal host–parasite interactions and the rarity of parasites compared to their free-living counterparts. As a result, our understanding of the ecology and evolution of most social parasites remains limited. Using whole-genome and reduced-representation sequence data, we conducted a study to fill knowledge gaps on host use, colony social structure, and population genetics of the facultative dulotic ant Formica aserva Forel. Our study reveals the remarkable ability of F. aserva to exploit at least 20 different host species across its wide geographic distribution. In some cases, one social parasite colony exploits multiple hosts simultaneously, suggesting a high degree of generalization even at a local spatial scale. Approximately 80% of the colonies were monogyne (with a single queen), with many exhibiting higher rates of polyandry compared to most Formica ants. Although we identified a supergene on chromosome 3, its association with colony structure remains uncertain due to the rarity of polygyny in our sample. Population genetic analyses reveal substantial geographic population structure, with the greatest divergence between California populations and those from the rest of the range. Mitochondrial population structure differs from structure inferred from the nuclear genome on a broad geographic scale, suggesting a possible role of adaptive introgression or genetic drift.This study provides valuable insights into the ecology and evolution of F. aserva, underscoring the need for further research to decipher the complexities of host interactions and the genetic mechanisms that regulate social structure.

Pest management based on CRISPR/Cas9-mediated site-specific mutations is an effective and environmentally safer strategy to suppress the pest population. However, the potential of this approach is yet to be tested on many important agricultural pests such as Bactrocera dorsalis (Hendel) (Diptera: Tephritidae), a fit candidate for area-wide pest management. Therefore, in the present study, 2 spermatogenesis-related genes viz. Testis-specific zinc finger protein (topi) and Testis-specific serine protein kinase 1 (Tssk1) of B. dorsalis were edited to impart male sterility and its impact on further progeny. In this regard, topi and Tssk1 mutant populations deposited significantly fewer eggs per day (6.12 ± 0.36 and 3.60 ± 0.24, respectively) as compared to the control (11.16 ± 0.58 eggs per day). About the hatching rate, the above trend was observed, topi (44.51) and Tssk1 (30.04) as compared to the control (73.96). Furthermore, the total number of viable offspring for topi and Tssk1 populations decreased as a result of the cumulative progeny production ten days after the post-mating phase. It suggests that topi and Tssk1 from B. dorsalis could be potential targets for imparting male sterility in B. dorsalis.

Graphical Abstract