Search

The widely distributed tropical species Psyllipsocus yucatan Gurney is recorded from several localities in Thailand. P. yongi New & Lee, previously only known from Peninsular Malaysia, is recorded from Thailand and its male is described for the first time. Four new species are described and illustrated: P. formosus Lienhard & Yoshizawa n. sp. (Peninsular Malaysia), P. sarawakensis Lienhard & Yoshizawa n. sp. (East Malaysia:Sarawak), P. siamensis Lienhard & Yoshizawa n. sp. (Thailand), P. hyalomarginatus Lienhard & Yoshizawa n. sp. (Thailand). A checklist of the 17 species of Psyllipsocus known from the Oriental Region is provided. The name of the Chinese species P. maculatus Li Fasheng, a junior homonym of the American P. maculatus Garcia Aldrete, is replaced by the new name P. apicosectus Lienhard & Yoshizawa n. nom.

A new species of the genus Trichadenotecnum (Psocodea: Psocidae) belonging to the corniculum species group,Trichadenotecnum okuyamai, was described from Awajishima Island, Japan. This is the 25th species of the genus and the third species of the corniculum group recorded from Japan.

We describe a new psocid genus and species, Burmesopsocus lienhardi Yoshizawa, based on a fossil specimen embedded in mid-Cretaceous Burmese (Kachin) amber. Phylogenetic analysis based on the morphological data strongly suggest that the species is a member of the suborder Psocomorpha and may belong to the infraorder Homilopsocidea. However, its familial placement could not be determined. Therefore, this species is treated here as incertae sedis within Homilopsocidea without assigning it to any known family. This is the oldest fossil record of Psocomorpha and represents the first occurrence of the suborder from Kachin amber. The present discovery of a mid-Cretaceous homilopsocid species will contribute greatly to calibrating the time tree of Psocodea.

Two species of psocids discovered from the Mid-Cretaceous Burmese amber, Latempheria kachinensis Li, Yoshizawa, and Yao, gen. et sp. nov. and Burmempheria curvatavena Li, Yoshizawa, and Yao, sp. nov., are described and assigned to the Empheriidae (Trogiomorpha: Atropetae) family. A phylogenetic analysis of the infraorder Atropetae is conducted based on 38 morphological characters of three outgroups and fifteen ingroups, which supported the monophyly of Atropetae including fossil and extant taxa. In the phylogenetic result, all the genera of fossil families Empheriidae and Archaeatropidae form a monophyletic group, sister to the extant members of Atropetae. The two fossil families also share a lot of similarities in morphology, locality, and geological period. Recently discovered fossil species exhibited combined morphological characters of both families. Based on these observations and the results of the phylogenetic analysis, Archaeatropidae is treated here as a new junior synonym of Empheriidae.

Five new species of the corniculum species group of the psocid genus Trichadenotecnum Enderlein, T. alfonsoi, T. lingens, T. palmula, T. affinifelix and T. separatum were described from Thailand. These species share a couple of male genital apomorphies with the other Oriental species of this species group recorded from China, Hong Kong, Malaysia, Singapore and Indonesia. The Japanese species of the corniculum group are considered to form a different clade placed to the sister of the Oriental species.

Supplementary Table. Comparisons of the result of the ancestral state reconstruction under different evolutionary models (one parameter Mk1 vs two parameter AsymmMK models): 1) presence or absence of the spermapore tubercule; 2) presence or absence of the basal shaft; 3) presence or absence of the muscle 5; and 4) presence or absence of the female penis.

Although the great genital diversity of the barklouse genus Trichadenotecnum has been described in previous studies, the specific function of the genital structures during the copulation process has received less investigative attention. We reconstructed 3D‐models of each structure of the male and female genitalia of Trichadenotecnum incognitum in copula and those of uncopulated male and female of Trichadenotecnum pseudomedium. By comparing the changes in male and female genital structures and related muscles in copulated and uncopulated states, the function of each genital structure can be described. During the copulation, we found that the female subgenital plate was hooked into the male body by the distal process on the male paraproct and was fixed by the male epiproct, hypandrium and phallosome. In addition, sexual coevolution was suggested by tightly contacting structures, that is, thorny male hypandrium and thickened membrane around the female spermapore plate. These results not only give us a new understanding copulation process of Trichadenotecnum, but also explain the reasons why genital structures are so divers in the genus.

The genus Neotrogla (Psocodea: Prinoglarididae) comprises four named species from Brazil. Females of this cave‐dwelling insect are characterized by a conspicuous penis‐like intromittent organ, termed a gynosome, which is inserted into the vagina‐like male genitalia during copulation. Another evolutionarily novel structure, the spermathecal plate, enables a female to simultaneously store two freshly deposited spermatophores (consisting of sperm and possibly nutritious substances) in her sperm storage organ (spermatheca). It is unknown whether the two spermatophores are derived from two different males. To investigate the mating ecology and population genetic structures of these insects with sex‐reversed genitalia, 16 novel highly polymorphic microsatellite loci were isolated and characterized based on ～2,275 Mbp genomic sequences from an undescribed Neotrogla species. Our first screening detected 99,888 candidate loci. Similar to other hemipteroid insects studied thus far, AAT motif microsatellites were conspicuously dominant. We further screened 99 sequences, for which 50 pairs of polymerase chain reaction primers were successfully designed. Sixteen of these primers successfully amplified products of the expected size in the 11 Neotrogla sp. individuals collected from two caves. The number of alleles per loci varied from two to nine, with no significant deviation from the Hardy–Weinberg equilibrium in either population. Although the caves sampled were only approximately 1 km apart, significant genetic differentiation was detected between the two populations. In total, 13, 12, 13 and 11 loci were cross‐amplified in N. aurora, N. brasiliensis, N. curvata and N. truncata, respectively, indicating the applicability of these microsatellite loci for metapopulation genetic studies in multiple Neotrogla species.