A new species of the chalcid-wasp genus Ericydnus walker (Hymenoptera, Chalcidoidea, Encyrtidae) from West Siberia

A new species, Ericydnus novosibiricus sp. n., is described. The main characters differentiating the new species from the similar E. longicornis Dalman are as follows: female??fore wing noticeably shortened, with almost normally developed veins and rounded apex, marginal vein longer than postmarginal vein, 6th flagellar segment slightly longer than wide, club truncate; male??fore wing noticeably shortened, with almost normally developed veins and pointed apex, flagellar segments subsequently becoming wider toward antennal apex.     

Insights into the molecular mechanisms underlying diversified wing venation among insects

Insect wings are great resources for studying morphological diversities in nature as well as in fossil records. Among them, variation in wing venation is one of the most characteristic features of insect species. Venation is therefore, undeniably a key factor of species-specific functional traits of the wings; however, the mechanism underlying wing vein formation among insects largely remains unexplored. Our knowledge of the genetic basis of wing development is solely restricted to Drosophila melanogaster. A critical step in wing vein development in Drosophila is the activation of the decapentaplegic (Dpp)/bone morphogenetic protein (BMP) signalling pathway during pupal stages. A key mechanism is the directional transport of Dpp from the longitudinal veins into the posterior crossvein by BMP-binding proteins, resulting in redistribution of Dpp that reflects wing vein patterns. Recent works on the sawfly Athalia rosae, of the order Hymenoptera, also suggested that the Dpp transport system is required to specify fore- and hindwing vein patterns. Given that Dpp redistribution via transport is likely to be a key mechanism for establishing wing vein patterns, this raises the interesting possibility that distinct wing vein patterns are generated, based on where Dpp is transported. Experimental evidence in Drosophila suggests that the direction of Dpp transport is regulated by prepatterned positional information. These observations lead to the postulation that Dpp generates diversified insect wing vein patterns through species-specific positional information of its directional transport. Extension of these observations in some winged insects will provide further insights into the mechanisms underlying diversified wing venation among insects.     

A new anaxyelid wood wasp (Hymenoptera: ‘Symphyta’) from the mid-Cretaceous Burmese amber

A new genus and species of anaxyelid wasp is described and figured from the mid-Cretaceous Burmese amber as Curvitexis kopylovi gen. et sp. nov. The placement of this new genus within the Anaxyelidae is corroborated by its wing venation and the configuration of its mesosoma. This new genus differs from all other Syntexinae from the mid-Cretaceous Burmese amber biota, inter alia, owing to its forewing with the vein 1Rs curved and longer than 1M, the crossvein 1r-rs absent, the vein 2Rs + M present; the hind wing with the abscissa 2M + Cu present, the vein m-cu absent, and the cell r closed. The recently described Paraxiphydria resinata Gao et al., 2022 is transferred to Anaxyelidae: Syntexinae, and the subfamily Paraxiphydriinae Gao et al., 2022 is synonymized under Syntexinae.     

Dpp/BMP transport mechanism is required for wing venation in the sawfly Athalia rosae

The pattern of wing venation varies considerably among different groups of insects and has been used as a means of species-specific identification. However, little is known about how wing venation is established and diversified among insects. The decapentaplegic (Dpp)/bone morphogenetic protein (BMP) signaling pathway plays a critical role in wing vein formation during the pupal stages in Drosophila melanogaster. A key mechanism is BMP transport from the longitudinal veins (LVs) to the posterior crossvein (PCV) by the BMP-binding proteins, short gastrulation (Sog) and twisted gastrulation2/crossveinless (Tsg2/Cv). To investigate whether the BMP transport mechanism is utilized to specify insect wing vein patterns in other than Drosophila, we used the sawfly Athalia rosae as a model, which has distinct venation patterns in the fore- and hindwings. Here, we show that Ar-dpp is ubiquitously expressed in both the fore- and hindwings, but is required for localized BMP signaling that reflects distinct wing vein patterns between the fore- and hindwings. By isolating Ar-tsg/cv in the sawfly, we found that Ar-Tsg/Cv is also required for BMP signaling in wing vein formation and retains the ability to transport Dpp. These data suggest that the BMP transport system is widely used to redistribute Dpp to specify wing venation and may be a basal mechanism underlying diversified wing vein patterns among insects.     

A new genus and species of tettigarctid cicada from the early Miocene of New Zealand: Paratettigarcta zealandica (Hemiptera,Auchenorrhyncha, Tettigarctidae)

A new genus and species of primitive cicada (Hemiptera: Tettigarctidae) is described from the early Miocene of southern New Zealand. Paratettigarcta zealandica gen. et sp. n. is the first cicada (Cicadoidea) fossil from New Zealand and exhibits wing venation patterns typical for the subfamily Tettigarctinae. It differs from other fossil taxa and the extant genus Tettigarcta in the early divergence of CuA2 from the nodal line in the forewing, its parallel-sided subcostal cell, the early bifurcation of vein M and long apical cells of the hindwing, and in wing pigmentation patterns.     

Character displacement in the fighting colours of Hetaerina damselflies

Aggression between species is a seldom-considered but potentially widespread mechanism of character displacement in secondary sexual characters. Based on previous research showing that similarity in wing coloration directly influences interspecific territorial aggression in Hetaerina damselflies, we predicted that wing coloration would show a pattern of character displacement (divergence in sympatry). A geographical survey of four Hetaerina damselfly species in Mexico and Texas showed evidence for character displacement in both species pairs that regularly occurs sympatrically. Hetaerina titia, a species that typically has large black wing spots and small red wing spots, shifted to having even larger black spots and smaller red wing spots at sites where a congener with large red wing spots is numerically dominant (Hetaerina americana or Hetaerina occisa). Hetaerina americana showed the reverse pattern, shifting towards larger red wing spots where H. titia is numerically dominant. This pattern is consistent with the process of agonistic character displacement, but the ontogenetic basis of the shift remains to be demonstrated.     

World Catalogue of the Family Ratardidae (Lepidoptera,Cossoidea) with Description of a New Species from Thailand and Establishment of New Synonymy and a New Status for <Emphasis Type="Italic">Ratarda javanica</Emphasis> Roepke, 1937

An illustrated catalogue is given of the family Ratardidae in the world fauna which includes 10 species from 3 genera. A new species, Callosiope elenae Yakovlev sp. n., is described from Lampang Province, Thailand. Externally, the new species differs well from the type species of the genus, C. banghaasi. The fore wing of C. elenae sp. n. has a pattern of alternating wide black bands against pure white background (in C. banghaasi, the fore wing is strongly darkened, without bands). The hind wing of C. elenae sp. n. shows a pattern of large dropshaped black smears at the wing edge and a more or less expressed spotted pattern in the discal and postdiscal areas (in C. banghaasi, the hind wing is completely black, with no pattern). A new synonymy: Ratarda marmorata Moore, 1879 = Ratarda guttifera Hering, 1925 syn. n. and a new status: Ratarda mora javanica Roepke, 1937 stat. n., are established. Ratarda excellens (Strand, 1917) is recorded in the fauna of Thailand for the first time.     

Broad-complex functions in postembryonic development of the cockroach Blattella germanica shed new light on the evolution of insect metamorphosis

Background

Insect metamorphosis proceeds in two modes: hemimetaboly, gradual change along the life cycle; and holometaboly, abrupt change from larvae to adult mediated by a pupal stage. Both are regulated by 20-hydroxyecdysone (20E), which promotes molts, and juvenile hormone (JH), which represses adult morphogenesis. Expression of Broad-complex (BR-C) is induced by 20E and modulated by JH. In holometabolous species, like Drosophila melanogaster, BR-C expression is inhibited by JH in young larvae and enhanced in mature larvae, when JH declines and BR-C expression specifies the pupal stage.

Methods

Using Blattella germanica as a basal hemimetabolous model, we determined the patterns of expression of BR-C mRNAs using quantitative RT-PCR, and we studied the functions of BR-C factors using RNA interference approaches.

Results

We found that BR-C expression is enhanced by JH and correlates with JH hemolymph concentration. BR-C factors appear to be involved in cell division and wing pad growth, as well as wing vein patterning.

Conclusions

In B. germanica, expression of BR-C is enhanced by JH, and BR-C factors appear to promote wing growth to reach the right size, form and patterning, which contrast with the endocrine regulation and complex functions observed in holometabolous species.

General significance

Our results shed new light to the evolution from hemimetaboly to holometaboly regarding BR-C, whose regulation and functions were affected by two innovations: 1) a shift in JH action on BR-C expression during young stages, from stimulatory to inhibitory, and 2) an expansion of functions, from regulating wing development, to determining pupal morphogenesis.     

Discovery of the genus Iasvia Zalessky, 1934 in the Upper Permian of France (Lodève basin) (Orthoptera, Ensifera, Oedischiidae)

New material attributed to the species Iasvia reticulata ZALESSKY, 1934 and to a new species in this genus is described from the Salagou Formation (Saxonian Group, Lodève basin). Preamble to the taxonomic section, the wing venation pattern of Orthoptera is discussed. The numerous described specimens yield decisive information about variability of wing venation within the genus, previously based on a single specimen from the Russian Permian. I. reticulata is the first species from the Lodève basin that is already known from another site. The biostratigraphic implications are discussed.     

A hitchhiker’s guide to parasite transmission: The phoretic behaviour of feather lice

Transmission to new hosts is a fundamental challenge for parasites. Some species meet this challenge by hitchhiking on other, more mobile parasite species, a behaviour known as phoresis. For example, feather-feeding lice that parasitise birds disperse to new hosts by hitchhiking on parasitic louse flies, which fly between individual birds. Oddly, however, some species of feather lice do not engage in phoresis. For example, although Rock Pigeon (Columba livia) “wing” lice (Columbicola columbae) frequently move to new hosts phoretically on louse flies (Pseudolynchia canariensis), Rock Pigeon “body” lice (Campanulotes compar) do not. This difference in phoretic behaviour is puzzling because the two species of lice have very similar life cycles and are equally dependent on transmission to new hosts. We conducted a series of experiments designed to compare the orientation, locomotion and attachment capabilities of these two species of lice, in relation to louse flies. We show that wing lice use fly activity as a cue in orientation and locomotion, whereas body lice do not. We also show that wing lice are more capable of remaining attached to active flies that are walking, grooming or flying. The superior phoretic ability of wing lice may be related to morphological adaptations for life on wing feathers, compared to body feathers.     

Anchor negatively regulates BMP signalling to control Drosophila wing development

G protein-coupled receptors play particularly important roles in many organisms. The novel Drosophila gene anchor is an orthologue of vertebrate GPR155. However, the roles of anchor in molecular functions and biological processes, especially in wing development, remain unknown. Knockdown of anchor resulted in an increased wing size and additional and thickened veins. These abnormal wing phenotypes were similar to those observed in BMP signalling gain-of-function experiments. We observed that the BMP signalling indicator p-Mad was significantly increased in wing discs in which anchor RNAi was induced in larvae and accumulated abnormally in intervein regions in pupae. Furthermore, the expression of target genes of the BMP signalling pathway was examined using a lacZ reporter, and the results indicated that omb and sal were substantially increased in anchor-knockdown wing discs. An investigation of genetic interactions between Anchor and the BMP signalling pathway revealed that the thickened and ectopic vein tissues were rescued by knocking down BMP levels. These results suggested that Anchor functions to negatively regulate BMP signalling during wing development and vein formation.     

Lodetiella magnifica nov. gen. and nov. sp. (Insecta: Palaeodictyoptera; Permian), an extreme situation in wing morphology of palaeopterous insects

Based on published data and review of Mecynoptera splendida Handlirsch, 1904, a wing venation ground plan applicable to most taxa of the Palaeozoic superorder Palaeodictyopteroidea is proposed, where each major vein system has a simple anterior sector, and, primitively, a dichotomously branched posterior sector. Lodetiella magnifica nov. gen. and sp. is described, based on an isolated hind wing from the Salagou Formation (Middle to Late Permian; Hérault, France). The venation of Lodetiella magnifica conforms to the predicted ground plan, but differs by its simple posterior cubitus sector. This character is diagnostic of the family Calvertiellidae (Palaeodictyoptera), whose diagnosis is updated. Wing movement in flight is inferred from the peculiar wing vein organization of Lodetiella magnifica. Some ecological preferences might explain the relative rarity of calvertiellids in the fossil record.     

A new form of <Emphasis Type="Italic">Kailasius autocrator</Emphasis> (Lepidoptera,Papilionidae) from the eastern Pamirs

A new subspecies, Kailasius autocrator pshartanus, from the eastern Pamirs (the Muzkol Ridge, Sasyk River) is described. The new subspecies is distinguished from the nominative subspecies by the wing pattern and ecology. This subspecies has the most primitive wing pattern in the genus. The range of this species is considered to be the center of Kailasius genus origin.     

The fourth new species of the leafhopper genus Thaioneura Song,Li & Dietrich from China (Hemiptera,Cicadellidae, Typhlocybinae)

In this paper, one new species of the leafhopper genus Thaioneura Song, Li & Dietrich, 2016 from Guizhou Province, China are described and illustrated: Thaioneura huajiangensis sp. nov. And the female ovipositors are photographed and described. A key to distinguish all known species of the genus is provided. The hind wing venation of the new species are the same as the T. suphanburia and T. sinuata, and not common in the tribe Erythroneurini.