Evolution of sexual conflict in scorpionflies.

Sexual conflict - opposite reproductive/genetic interests between sexes - can be a significant driver of insect evolution. Scorpionflies (Insecta: Mecoptera) are models in sexual conflict research due to their large variety of mating practices, including coercive behaviour and nuptial gift provisioning. However, the role of palaeontology in sexual conflict studies remains negligible, namely due to the paucity of well-preserved fossils. Here, we describe three male scorpionflies from Cretaceous and Eocene ambers. The structure of notal and postnotal organs is analysed in extant and extinct forms; a depression below the base of the notal organ in different panorpid species spatially matches the anterior fold of the female's wing. Based on disparate abdominal configurations and correlations in extant relatives, we posit that each new fossil taxon had a different mating approach along a nuptial gifting-coercive spectrum. The Eocene specimen possesses extreme female clamping abdominal armature, suggesting a degree of sexual coercion greater than in any other known scorpionfly, extinct or extant. The fossil record of abdominal modifications in male scorpionflies documents a relatively late evolution (Eocene) of long notal organs indicating oppressive behaviour toward a female during mating. Our findings reveal a wider array of mating-related morphological specialisations among extinct Panorpoidea, likely reflecting more diversified past mating strategies and behaviours in this group, and represent first steps towards gaining a deep-time perspective on the evolution of sexual conflict over mating among insects.

Diversity of the Fossil Genus Palaeoglaesum Wagner (Diptera, Psychodidae) in the Upper Cretaceous Amber of Myanmar.

Cretaceous Myanmar amber is abundant in inclusions belonging to the genus Palaeoglaesum. In addition, a significant morphological diversity among representatives of Palaeoglaesum can be observed. However, none of its representatives have been found in other fossil materials. Herein three new species: P. stebneri sp. nov., Skibinska and Krzeminski P. teres sp. nov. Skibinska and Albrycht, and P. pilosus sp. nov. Skibinska, Krzeminski and Zhang from Cretaceous Myanmar amber are described and illustrated. The very small size and characters of male hypopygium with aedeagus strongly bent and apically forked are pertinent to diagnosing the genus and species. New materials show that this genus and the whole subfamily Bruchomyiinae were probably more abundant and more diverse than the presently known extant fauna.

A Peculiar New Genus of Bibionomorpha (Diptera) with Brachycera-Like Modification of Antennae from Mid-Cretaceous Amber of Myanmar.

A new fossil genus of Bibionidae (Diptera: Bibionomorpha), Burmahesperinus gen. nov., from the mid-Cretaceous Burmese amber, is described and illustrated (type species Burmahesperinus antennatus sp. nov., the other two species included are B. conicus sp. nov. and B. pedicellatus sp. nov.). The new genus is tentatively placed in a new subfamily, Burmahesperininae subfam. nov. of the family Bibionidae. Its possible phylogenetic position is briefly discussed. The new genus, as well as the subfamily, possesses the wing venation similar to the recent genus Hesperinus Walker, 1848, in combination with Brachycera-like modification of both the male and female antenna and the overall habitus typical of fungus gnats (Sciaroidea).

Paleotelmatoscopus, a proposed new genus for some fossil moth flies (Diptera, Psychodidae, Psychodinae) in Eocene Baltic amber, with description of a new species.

Few species of Baltic amber Psychodinae have been described to date. Some were incorrectly classified in Pericoma Walker based on an early, broad definition of the genus and holotypes were not specified. We examined approximately 50 specimens of Baltic amber Psychodinae in addition to reviewing the original series studied by Fernand Meunier. Lectotypes for Pericoma formosa Meunier and P. speciosa Meunier are designated and Paleotelmatoscopus gen. nov. is proposed to include P. formosa and P. madrizi sp. nov. Characters included in the diagnosis of this new genus and species have implications for future descriptions of Baltic amber Psychodinae. Parts of the head capsule, such as antennae, are often well-preserved and visible, and can be useful for separating species. However, these character complexes are prone to homoplasy and should not be used alone to define genera. Since it is impossible to view internal genitalic characters in fossil species, refinement of generic and species diagnoses based on external morphology is a critical factor in describing the amber fauna.

Extant Genus in the Mesozoic: Paleoplatyura Meunier (Diptera: Keroplatidae) Found in the Cretaceous Amber of Myanmar.

Three new species of Paleoplatyura Meunier, 1899, i.e., Paleoplatyura agnieszkae sp. nov., P. miae sp. nov., and P. magnifica sp. nov., are described and figured. The concept of the genus is briefly discussed, and its systematic position is clarified. A key to fossil species is provided. The genus Paleoplatyura is described from the Eocene Baltic amber. It is concluded that, in Baltic amber, this group is represented only by the type species, and the identity of the other two species is problematic. No additional specimens have been found so far in this amber. Therefore, the presence of as many as three new species in Burmese amber, certainly belonging to Paleoplatyura, is a confirmation of its occurrence already in the Mesozoic.

A new species of Bruchomyiinae (Diptera: Psychodidae) from Baltic amber.

Bruchomyiinae is one of seven subfamilies of Psychodidae. This small group comprises fewer than 60 extant species distributed mainly in tropical and sub-tropical regions (Wagner Stuckenberg 2016). All life stages of these flies are closely tied to forest environment (Fairchild 1952; Stuckenberg 1962) and as a result, bruchomyiines are frequently preserved in fossil resins. The first fossil member of this subfamily was described from Baltic amber (45 Ma) (Meunier 1905) and Burmese amber (100 Ma) is the oldest fossil resin in which representatives of Bruchomyiinae have been found (Stebner et al. 2015; Wagner 2017; Skibinska et al. 2019). Due to the relative scarcity of this subfamily in Baltic amber, any new specimens are of great interest. Up till now, there are only 12 bruchomyiine species described from Baltic amber. Wagner (2017) completed a revision of fossil Bruchomyiinae and proposed the genus Hoffeinsodes to include the species having male genitalia with gonocoxites fused with hypandrium. In this genus, he classified six species reported exclusively from Eocene Baltic amber: H. bifida Wagner, 2017, H. cubicula Wagner, 2017, H. longicauda Wagner, 2017, H. obtusa Wagner, 2017, H. reducta Wagner, 2017 and H. hoffeinsi (Wagner, 2006) transferred from Nemopalpus (Wagner, 2006). Here, we describe a new species belonging to this genus.

Intriguing and Beautiful: Adamacrocera adami gen. et sp. nov. from the Upper Cretaceous Amber of Myanmar Represents a New Subfamily of Keroplatidae (Diptera: Bibionomorpha).

A new fossil genus and species of Keroplatidae (Diptera, Bibionomorpha, Sciaroidea), Adamacrocera adami gen. et sp. nov., from the Upper Cretaceous Burmese amber is described and illustrated. Based on morphological evidence, it is placed in a new subfamily Adamacrocerinae subfam. nov. The new genus, as well as the subfamily, possesses the wing venation characteristic of the genera of some Sciaroidea incertae sedis, as well as that of the fossil families Archizelmiridae, Antefungivoridae and Mesosciophilidae, in combination with macrocerine-like habitus and male terminalia.

Discovery of the most ancient member of family Tanyderidae (Diptera) from the Lower Jurassic (Sinemurian) of England.

Nannotanyderus oliviae sp. nov. from the Lower Jurassic (Sinemurian) of England, the oldest representative of family Tanyderidae, is described and illustrated.