Evolving longer for a mate: A new scorpionfly (Mecoptera: Panorpoidea: Panorpidae) with exaggeratedly elongated male abdominal segments.

Male scorpionflies often evolve exaggeratedly elongated abdominal segments (EEAS) that are used as a sexual display to the females, and a combat weapon in intra-sexual disputes. EEAS have independently evolved several times since the Jurassic till the present day in at least eight genera and four families. In this paper, Neopanorpa exaggerata sp. n. with EEAS is described from Yunnan Province, China. Through comparisons among extinct and extant species, our current knowledge is summarized for the evolution, copulatory mechanism, and biogeography of the scorpionflies with EEAS. Also discussed are the trade-offs between the benefits of "looking sexy" and the negative impacts associated with a long abdomen. Additionally, further clarification is provided on the multiple origins of EEAS in Panorpoidea.

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.

Taxonomy of the Panorpa guttata group (Mecoptera: Panorpidae), with descriptions of fourteen new species from China.

Panorpa Linnaeus, 1758 is the largest genus in the scorpionfly family Panorpidae. It is considered a paraphyletic taxon and needs further revisions. In this paper, we present a taxonomic study of the Panorpa guttata group, including 23 closely related species, with fourteen species new to science: Panorpa caoweii Wang, sp. n., Panorpa dali Wang, sp. n., Panorpa duanyu Wang Gong, sp. n., Panorpa hani Wang, sp. n., Panorpa hirundo Wang, sp. n., Panorpa huangguiqiangi Wang, sp. n., Panorpa jiangrixini Wang, sp. n., Panorpa jinfoshana Wang, sp. n., Panorpa latiloba Wang, sp. n., Panorpa nanzhao Wang, sp. n., Panorpa stella Wang, sp. n., Panorpa substricta Wang, sp. n., Panorpa xiaofeng Wang Gong, sp. n., and Panorpa xuzhu Wang Gong, sp. n. We also provide a distributional map, keys to species, and discussions regarding the taxonomic implications and biological information of the P. guttata group.

Discovery of the genus Dioedus LeConte, 1862 from China, with description of a new species (Coleoptera: Tenebrionidae).

The genus Dioedus LeConte, 1862 (Coleoptera: Tenebrionidae: Phrenapatinae: Penetini) is recorded from China for the first time. A new species Dioedus liuhaoyii Jiang, Wang Wang sp. nov. is described from Henan Province, China. Habitus and diagnostic features of the adult of the new species are described and illustrated.

First Report of Necrophilia in the Form of Necrocoitus among Insects, Involving Two Male Cryptotympana atrata (Fabricius, 1775) Cicadas.

The unusual case of a male Cryptotympana atrata cicada from China attempting to mate with a dead male conspecific is described and illustrated. Although hitherto unreported, necrophilic behaviour in the form of an attempted necrocoitus, involving dead male or female corpses, may not be as isolated a case as has been previously assumed, but it does not seem to have been mentioned earlier in the entomological literature. Although the described behaviour could have been an expression of a lack of opportunity to locate a cooperative female, several other possibilities, referred to in the Discussion, exist and should not be dismissed.

Two new species of the genus Panorpa (Mecoptera, Panorpidae) from eastern China and a new synonym.

Panorpa Linnaeus, 1758 is the largest genus in the scorpionfly family Panorpidae. Herein we describe two new species from eastern China, Panorpa jinhuaensis sp. nov. from Jinhua, Zhejiang Province and Panorpa menqiuleii sp. nov. from Yuexi and Huoshan, Anhui Province. Panorpa wrightae Cheng, 1957 from Mount Mogan, Zhejiang Province is considered to be a junior subjective synonym of Panorpa mokansana Cheng, 1957 from the same locality. Panorpa mokansana Cheng, 1957 is redescribed and illustrated in detail. A key to species of Panorpa from eastern China is also provided.

Molecular phylogeny of the scorpionflies Panorpidae (Insecta: Mecoptera) and chromosomal evolution.

Panorpidae is the most species-rich family in Mecoptera with ca. 470 species in the Northern Hemisphere. However, the intergeneric phylogenetic relationships of Panorpidae remain unsatisfactorily resolved to date. Here, we used molecular and cytogenetic approaches to determine the phylogenetic relationships of Panorpidae in the evolutionary scenario of chromosomes, and estimated their divergence times using fossil-calibrated Bayesian analysis. In total, 89 species representing all seven genera of Panorpidae were used to reconstruct the phylogenetic trees using maximum parsimony, maximum likelihood and Bayesian inference based on the nuclear 28S rRNA and mitochondrial cox1 and cox2 genes. The results reveal that Panorpidae is a well-supported monophyletic group that can be categorized into two major clades. Major Clade I comprises Neopanorpa and Leptopanorpa, and Major Clade II consists of all the other genera (Cerapanorpa, Dicerapanorpa, Furcatopanorpa, Panorpa and Sinopanorpa). Neopanorpa and Cerapanorpa are regarded as paraphyletic groups for the first time. BEAST analysis indicates that Panorpidae originated in the Lower Cretaceous approximately 122.5 Ma (96.8-149.3 Ma), and that most diversification occurred from the Selandian (59.8 Ma) to the Middle Pleistocene (0.6 Ma) in the Cenozoic. Cytogenetic data plotted on the cladogram show that the lineage differentiation of Panorpidae is closely related to the chromosomal evolution, especially the reduction of chromosome number. Our study suggests that a taxonomic revision of Panorpidae is urgently needed at the generic level.

Two new species of the genus Panorpa Linnaeus (Mecoptera, Panorpidae) from Yunnan, China.

Two new scorpionfly species, Panorpa reflexa sp. n. and Panorpa parallela sp. n., are described and illustrated from Yunnan Province, China. Panorpa reflexa can be readily differentiated from its congeners by the 3-shaped parameres in male genitalia. Panorpa parallela is unique for its parallel parameres in male genitalia. The number of Panorpa species is raised to four in Yunnan Province, and to 113 throughout China.