(Figs. 56–61)

Specimens examined. 2 males, Czech Republic, “ Moravia, mar. 30.5.1975, Konice u Znojma 11/75, Popicky vrch, 290 m, lgt. J. L. Stehlik ”, “ Collectio J. L. Stehlik Mor. museum, Brno”, “ Heterogaster urticae (Fabricius) det J.L. Stehlik 1976”, in VAIC.

Ashlock (1957) provided notes on the phallus of Heterogastridae without being able to successfully inflate the inflatable parts of the endosoma of representatives of the family. His notes were therefore based on Servedei (1951) who had described and figured the phallotheca and part of the inflatable portions of the endosoma of Heterogaster urticae (Fabricius). On close examination I find this figure, reproduced in Schuh & Weirauch (2020), rather inaccurate since it was based on an incompletely inflated portion of endosoma. Therefore, a detailed corrected figure and description of aedeagus of this species, along with those Parathyginus species included in the present contribution, are given as the first representatives of the family Heterogastridae.

Following Ashlock, Henry (1997) scored the character and states in his matrix table and interpreted “not inflatable conjunctiva” as derived, a major character grouping Heterogastridae with the family Pachygronthidae in his cladistic analysis of the Lygaeoidea. Considering the present study, the foresaid character needs to be reassessed and rescored, and its implications on the relationships of these and related families be reviewed.

In the present study, I successfully and fully inflated the endosoma (conjunctiva + vesica) to provide the following detailed description.

The basal plate (articulatory apparatus) (Fig. 56), only partly fused with the highly sclerotized and pigmented phallotheca (Fig. 57, ph). The phallotheca in upper view (Fig. 58), with antero-lateral margins of distal end produced to sclerotized arm like processes, area between the arms, where the conjunctiva attaches (Fig. 57, co), is slightly less pigmented in pattern seen in Fig. 58; in lateral view the phallotheca (Fig. 57, ph), lower surface (facing apodeme surface within pygophore) is uniformly but strongly curved, however the upper surface is rather bulbous and conspicuously constricted in distal 1/3. The conjunctiva (Fig. 57, co) is membranous, tubular and of slightly variable girth notably in distal half, extremely long about 4 times the length of phallotheca and about 5 times the length of vesica (Fig. 57, ve), sharply turned at a couple of places, the sharper turn seen at about half its length, and appears to have a pair of large membranous lobes (Fig. 59, cl), on its wall towards distal end, but lacking any processes. The seminal duct (ductus seminis) (Figs. 60, 61, sd) is not clearly visible through most of the length of the conjunctiva, but becomes distinct near ejaculatory reservoir (Fig. 60, er); ejaculatory reservoir is modified to heavily pigmented and sclerotized body and neck undifferentiated from vesical seminal duct, with traces of wings appearing to be distinct (Fig. 60); the seminal duct in vesica continues as a heavily pigmented and sclerotized narrow parallel sided plate that is gradually curved ventrally to end as a complex structure comprising gonoporal process and associated parts (Fig. 60, 61); vesica (Fig. 57, ve) short, tubular and appearing to possess one asymmetrical membranous lobe (Fig. 59, vl) near its base, but lacking any processes.

In summary, based on the dissections of Heterogaster urticae and the included species of Parathyginus the following comments may be made in relation to the aedeagal features. The conjunctiva is unusually long (about 5 times) compared to the vesica; the ejaculatory reservoir is highly modified and often greatly reduced; the vesica is short and tubular, with or without membranous lobes, but lacking any processes; and the vesical seminal duct is highly modified, gradually bending ventrally to end as a complex structure comprising gonoporal process and associated parts. A comprehensive review however of these unusual features in the family Heterogastridae and the related taxa is beyond the scope of this paper.