Pauesia species (Hymenoptera: Braconidae: Aphidiinae) attacking Eulachnini aphids (Hemiptera: Aphididae: Lachninae) on coniferous plants in Lithuania: ecological and mitochondrial COI diversity

Based on the original research data of 2018-2019, ten species of aphid parasitoids of the genus Pauesia (Hymenoptera: Braconidae: Aphidiinae) reared from 14 out of 27 available Eulachnini species (Hemiptera: Aphididae: Lachninae) are listed for Lithuanian fauna, seven species being recorded for the first time. No parasitoids were found in colonies of aphid genus Eulachnus, despite having inspected 24 colonies of four species of this genus. Parasitoids for aphid species Cinara (Cinara) hyperophila and C. (C.) piniphila were recorded for the first time. New parasitoid species were recorded for aphid host species C. (C.) brauni, C. (C.) neubergi, C. (C.) pinea, C. (C.) pini, and C. (C.) pruinosa. Summarized information on the distribution and host specificity of Pauesia species in Lithuania is presented. Partial sequences of the mitochondrial cytochrome c oxidase subunit 1 (COI) for 98 parasitoid individuals were analyzed. DNA-based species delimitation by means of Automatic Barcode Gap Discovery (ABGD), generalised mixed Yule-coalescent (GMYC) model, Poisson tree processes (PTP) model, and statistical parsimony network analysis (TCS) gave number of candidate species ranging from 11 to 15. The values of match ratio for each method were from 0.67 for PTP to 0.93 for GMYC. Maximum Likelihood, Maximum Parsimony, and Bayesian Inference analyses confirmed the paraphyly of the parasitoid subgenus Paraphidius. Sequence divergences (p-distances, %) between the parasitoid species Pauesia jezoensis, P. pinicollis, P. cupressobii, and P. goidanichi were on the intraspecific level (0.62-1.14%). Molecular delimitation methods indicate possible existence of three species new to science.

Automated summary

Based on original research data from Lithuania, this study documents ten species of aphid parasitoids of the genus Pauesia, with seven newly recorded. Analyses of DNA sequences suggest potential new species, indicating a high level of genetic diversity within these parasitoids. Further research is needed to fully understand the evolutionary relationships and diversity within this group.