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Arthropods are hosts to a variety of parasitic fungi, including those within the order of Laboulbeniales (Ascomycota, Laboulbeniomycetes). Species in the genus Hesperomyces are specialized in growing on ladybirds (Coccinellidae). Recent studies have uncovered multiple cryptic species within the Hesperomyces virescens species complex. They found that these species are segregated not only by host, but also by a geographic component. Here, we describe two new species in this species complex, based on morphological, molecular phylogenetic, ecological, and geographical evidence: Hesperomyces chilocori-bipustulati sp. nov. on Chilocorus bipustulatus from the Mediterranean region, and He. coccinellae-transversalis sp. nov. on Coccinella transversalis from Peninsular Malaysia. Hesperomyces chilocori-bipustulati is the second species known to associate with a representative of the genus Chilocorus, after He. virescens sensu stricto which was described from Ch. stigma from the USA. The findings of this paper contribute to our understanding of the diversity, host specificity, and biogeographical distribution within the Hesperomyces virescens species complex and highlight the need for further integrative taxonomy approaches in Laboulbeniales. [ABSTRACT FROM AUTHOR]

This study investigates the attachment ability of harlequin ladybird, Harmonia axyridis (Pallas) (Coleoptera: Coccinellidae), focusing on the synergic action of opposite legs, the anisotropy of adhesive organs and sexual dimorphism. Contrary to expectations, experiments showed that beetles with fewer legs sometimes exhibited higher attachment forces, challenging the hypothesis that collective leg action enhances attachment. This result is attributed to differences in experimental set‐ups, where our centrifugal method highlighted the importance of pad orientation relative to external forces. The anisotropy of adhesive pads, characterized by the directional dependence of adhesion and friction, significantly influenced attachment performance. Results demonstrated that inward‐oriented legs enhanced attachment due to lower peeling angles, whereas outward orientation reduced effectiveness. Sexual dimorphism was evident in the structure of adhesive pads, with males possessing discoidal setae on fore‐ and midlegs. No significant difference in attachment was observed between intact males and females on smooth surfaces, although ablated males sometimes showed higher forces due to the presence of discoidal setae. These findings underscore that attachment strength in H. axyridis is not solely dependent on pad area but also on the orientation and anisotropic properties of adhesive organs, as well as the specific role of sexual dimorphism in leg morphology. [ABSTRACT FROM AUTHOR]

Multiple mating is a behaviour observed across various polyandrous insect species. It is suggested that, in ladybirds, this strategy of multiple copulations is used to enhance fecundity and fertility through sperm replenishment. Studies on sperm depletion need to correlate fertility with the presence of spermatozoa in the spermatheca. This study investigates the role of sperm replenishment in the ladybird Cryptolaemus montrouzieri . We hypothesised that females of this species exhibit fecundity and fertility rates proportional to the number of sperm replenishment opportunities (constant, periodic or absent). We observed oviposition behaviour and hatching rates over 30 days, and simultaneously tested for sperm depletion in females that copulated once. We dissected the spermathecae at four post-copulation moments to count spermatozoa under a microscope. Our results indicate that a single copulation suffices to maintain fertility for at least 30 days. Females with constant replenishment opportunities exhibited higher fecundity but lower fertility and increased mortality, suggesting a reproductive cost associated with frequent mating. Females with no replenishment during the experiment, exhibited the highest hatchability rate and lowest oviposition. Periodic copulation resulted in optimal female mating rate, with average fertility and fecundity. A plausible hypothesis would be that paired females choose to fertilise fewer eggs from a single male but are unable to control the effects of the oviposition stimulus induced by the male's presence. These findings have implications for the management and rearing of C. montrouzieri in biological control programmes, optimizing mating strategies for mass production.