Couples in phoretic copulation, a tool for male-female association in highly dimorphic insects of the wasp genus Dissomphalus Ashmead (Hymenoptera: Bethylidae)

Abstract

ABSTRACT. It is difficult to make reliable sex associations in several species of Hymenoptera due to sexual dimorphism. Only a few species of the flat wasp genus Dissomphalus Ashmead, 1893 have had their sexes associated, since females are rarely collected and differ morphologically from their conspecific males. Collecting couples during their phoretic copula is difficult, but it is the most reliable way to associate the sexes in Dissomphalus. Herein, we associate the sexes and discuss the mating briefly discuss the genital structures used during phoretic copulation, analyzing the male and female genitalia in copulation.During copulation, the mating female is attached to the male only by the genitalia and is apparently grasped by muscles attached to the male's metasoma.

Opening Pandora's box of Pristocerinae: molecular and morphological phylogenies ofApenesia(Hymenoptera, Bethylidae) reveal several hidden genera

“…This species, which belonged to the dissomphaloides species group, was transferred to Dissomphalus by Azevedo et al . () based on genitalia morphology. The species of the dissomphaloides species group are characterized by having the mesonotum conspicuous below the margin of the mesosoma, and the mesopleuron callus in dorsal view and the metapectal‐propodeal complex with parallel sides.…”

“…Phoretic copulation has been reported for two genera of Pristocerinae, where the two sexes can be caught in copula in flight interception traps. Capture of these male–female pairs along with molecular tools is essential for credible sex association (Azevedo et al ., ).…”

Phoretic copulation in the velvet ant Sphaeropthalma pensylvanica (Lepeletier) (Hymenoptera, Mutillidae): A novel behavior for Sphaeropthalminae with a synthesis of mating strategies in Mutillidae

“…Within Mutillidae, this first subtype is known to occur in the myrmosine tribe Myrmosini and the subfamily Rhopalomutillinae (Table 1). "True phoretic copulation" also occurs in some subfamilies of Bethylidae and Thynnidae (Evans 1969;Osten 1999;Azevedo et al 2016). The other subtype is known to commonly occur in the subfamily Mutillinae (excluding Mutillini and Odontomutillini) and now in Sphaeropthalminae (S. pensylvanica) (Table 1), wherein the female is primarily supported by the male's mandibular clasp around her pronotal neck, and secondarily by his legs and terminalic union.…”

“…The female is carried by the male primarily by either grasping her around the pronotal neck with his mandibles or by their terminalic union. Phoretic copulation has been observed in three distantly-related families of aculeate Hymenoptera with apterous females: Bethylidae, Mutillidae, and Thynnidae (Evans 1969;Clausen 1976;Brothers 1989;Gordh 1990;Osten 1999;Azevedo et al 2016). Vivallo (2020) recently reviewed phoretic copulation in aculeate Hymenoptera as a whole with primary emphasis on Thynnidae and the biomechanical aspects of the behavior in that family.…”

A new genus and species of Pristocerinae (Hymenoptera, Bethylidae) from upper Eocene Baltic amber with a review of conspecific association from insect fossils

“…The subfamily is known for its remarkable sexual dimorphism, with males possessing robust bodies, wings, and conspicuous eyes and ocelli while females are wingless, lack ocelli, and have eyes that are extremely reduced or missing (Alencar et al 2018). The vast majority of Pristocerinae species are known from 'males-only' or 'females-only' and conspecific associations between males and females are rare, typically the result of collecting specimens copulating or rearing them from the same host (Azevedo et al 2016;Alencar et al 2018;Chen and Azevedo 2020).…”