Uncovering the Male Presence in Parthenogenetic Marchalina hellenica (Hemiptera: Marchalinidae): Insights into Its mtDNA Divergence and Reproduction Strategy

Simple Summary Marchalina hellenica (Hemiptera: Marchalinidae) is a significant contributor to annual honey production in Greece and Turkey, where it is endemic. It was initially described as parthenogenetic, producing only females. The exact reproduction strategy of this species remains unknown. For this reason, we studied the emergence pattern of male individuals in Greece for two consecutive years (2021 and 2022). Furthermore, we examined the genetic variation among 15 geographically distant populations of M. hellenica in Greece using a mitochondrial DNA marker and compared the results with data from Turkey. This study documents the existence of an additional M. hellenica population in its native range that repeatedly produces males, suggesting a previously unknown role for males in the species' reproduction. The Greek and Turkish populations exhibited a strong genetic affinity, while the genetic pattern in Greece seems to have been obscured by human-aided dispersal. Marchalina hellenica (Hemiptera: Marchalinidae), an endemic species in Greece and Turkey, is a major contributor to the annual honey production in its native range. However, in the areas that it invades, lacking natural enemies, it has detrimental effects on pine trees and potentially contributes to tree mortality. Although it was originally reported as thelytokous, males were later reported in Turkey and on several of the islands of Greece. To further disambiguate the exact parthenogenetic reproduction strategy of M. hellenica, we studied the emergence pattern of male individuals in Greece for two consecutive years (2021 and 2022). Furthermore, we examined the genetic variation among 15 geographically distant populations of M. hellenica in Greece using a mitochondrial DNA marker and compared the results with data from Turkey. The findings of this study document the existence of an additional M. hellenica population in its native range that repeatedly produces males, apart from the areas of Greece and Turkey in which they were initially reported, suggesting that males play a major, so far unknown role in the reproduction of this species. The populations in Greece and Turkey exhibited a strong genetic affinity, while human-aided dispersal seems to have obscured the genetic pattern acquired.