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Ponds are common freshwater habitats in the European landscape that substantially contribute to local and regional biodiversity. Chironomids often dominate invertebrate communities in ponds but are usually disregarded in ecological studies due to relatively complicated taxonomy and identification issues. We present a comprehensive overview of the chironomid diversity in 246 ponds spanning a wide range of conditions extending from the Pannonian Plain to the Carpathians. Altogether, we recorded 225 taxa including 192 species from six subfamilies (Podonominae, Tanypodinae, Diamesinae, Prodiamesinae, Orthocladiinae and Chironominae). However, the chironomid taxa inventory is far from complete and about 16% of the total diversity of pond‐dwelling chironomids remains undetected. Chironomid alpha diversity showed a significant unimodal pattern along the elevation gradient with the highest number of taxa per pond expected around 790 m a.s.l. Gamma diversity also peaked in mid‐elevations (600–800 m), and the common chironomid taxa partitioned the 2100‐m long altitudinal gradient relatively evenly. The heterogeneity of chironomid communities among ponds measured as beta diversity was significantly higher in elevations below 800 m. Temperature and the proportion of surrounding forests significantly influenced alpha diversity of chironomid communities, while urban land cover and pond size had no significant effect. Ponds with a mean annual air temperature of approximately 4.8°C and a low proportion of surrounding forests are expected to harbour the most diverse chironomid communities. Our study showed that chironomids represent a very diverse and often exceptionally rich group of pond‐dwelling macroinvertebrates. Given the high diversity and broad range of occupied niches, chironomids should not be overlooked in pond ecology studies. On the contrary, they should be considered a potential model group. [ABSTRACT FROM AUTHOR]

Six new species of Cryptochironomus Kieffer, 1918, C. absum Liu, sp. nov., C. beardi Liu, sp. nov., C. dentatus Liu, sp. nov., C. ferringtoni Liu, sp. nov., C. parallelus Liu, sp. nov. and C. taylorensis Liu, sp. nov., are described and illustrated based on adult males. The specimens were collected from various water systems in the United States and preserved by Dr. Leonard Charles Ferrington Jr. An updated key to adult males of all known Cryptochironomus species in the Nearctic region is also provided. [ABSTRACT FROM AUTHOR]

Specialized pollination systems frequently match a particular set of floral characteristics. Vincetoxicum spp. (Apocynaceae, Asclepiadoideae) have disk‐shaped flowers with open access to rewards and reproductive organs. Flowers with these traits are usually associated with generalized pollination. However, the highly modified androecium and gynoecium that characterize asclepiads are thought to be associated with specialized pollinators.In V. sangyojarniae, we investigated floral biology, pollination, and the degree of pollinator specialization in two localities in Thailand. We examined floral traits that target legitimate pollinators.Flowers of V. sangyojarniae opened only at night, emitted floral scents containing mainly (E)‐β‐ocimene, 1‐octen‐3‐ol, (E)‐4,8‐dimethyl‐1,3,7‐nonatriene (E‐DMNT) and N‐(3‐methylbutyl)acetamide, and provided sucrose‐dominated nectar openly to insect visitors. Assessment of pollinator effectiveness indicated that V. sangyojarniae is functionally specialized for pollination by cecidomyiid flies. Although various insects, particularly cockroaches, frequently visited flowers, they did not carry pollinaria.Our results suggest that V. sangyojarniae attracts its fly pollinators by emitting floral volatiles bearing olfactory notes associated with the presence of fungi or, less likely, of prey captured by predatory arthropods (food sources of its pollinators) but offers a nectar reward upon insect arrival. Hence, there is a mismatch between the advertisement and the actual reward. Our results also suggest that the size of floral parts constitutes a mechanical filter where reciprocal fit between flower and insect structures ensures that only suitable pollinators can extract the pollinaria, a prerequisite for successful pollination. [ABSTRACT FROM AUTHOR]

Abstract Ponds are common freshwater habitats in the European landscape that substantially contribute to local and regional biodiversity. Chironomids often dominate invertebrate communities in ponds but are usually disregarded in ecological studies due to relatively complicated taxonomy and identification issues. We present a comprehensive overview of the chironomid diversity in 246 ponds spanning a wide range of conditions extending from the Pannonian Plain to the Carpathians. Altogether, we recorded 225 taxa including 192 species from six subfamilies (Podonominae, Tanypodinae, Diamesinae, Prodiamesinae, Orthocladiinae and Chironominae). However, the chironomid taxa inventory is far from complete and about 16% of the total diversity of pond‐dwelling chironomids remains undetected. Chironomid alpha diversity showed a significant unimodal pattern along the elevation gradient with the highest number of taxa per pond expected around 790 m a.s.l. Gamma diversity also peaked in mid‐elevations (600–800 m), and the common chironomid taxa partitioned the 2100‐m long altitudinal gradient relatively evenly. The heterogeneity of chironomid communities among ponds measured as beta diversity was significantly higher in elevations below 800 m. Temperature and the proportion of surrounding forests significantly influenced alpha diversity of chironomid communities, while urban land cover and pond size had no significant effect. Ponds with a mean annual air temperature of approximately 4.8°C and a low proportion of surrounding forests are expected to harbour the most diverse chironomid communities. Our study showed that chironomids represent a very diverse and often exceptionally rich group of pond‐dwelling macroinvertebrates. Given the high diversity and broad range of occupied niches, chironomids should not be overlooked in pond ecology studies. On the contrary, they should be considered a potential model group.

The level of resistance to radiation and the developmental and molecular responses can vary between species, and even between developmental stages of one species. For flies (order: Diptera), prior studies concluded that the fungus gnat Bradysia (Sciara) coprophila (sub-order: Nematocera) is more resistant to irradiation-induced mutations that cause visible phenotypes than the fruit fly Drosophila melanogaster (sub-order: Brachycera). Therefore, we characterized the effects of and level of resistance to ionizing radiation on B. coprophila throughout its life cycle. Our data show that B. coprophila embryos are highly sensitive to even low doses of gamma-irradiation, whereas late-stage larvae can tolerate up to 80 Gy (compared to 40 Gy for D. melanogaster) and still retain their ability to develop to adulthood, though with a developmental delay. To survey the genes involved in the early transcriptional response to irradiation of B. coprophila larvae, we compared larval RNA-seq profiles with and without radiation treatment. The up-regulated genes were enriched for DNA damage response genes, including those involved in DNA repair, cell cycle arrest, and apoptosis, whereas the down-regulated genes were enriched for developmental regulators, consistent with the developmental delay of irradiated larvae. Interestingly, members of the PARP and AGO families were highly up-regulated in the B. coprophila radiation response. We compared the transcriptome responses in B. coprophila to the transcriptome responses in D. melanogaster from 3 previous studies: whereas pathway responses are highly conserved, specific gene responses are less so. Our study lays the groundwork for future work on the radiation responses in Diptera., Competing Interests: Conflicts of interest The author(s) declare no conflicts of interest., (© The Author(s) 2023. Published by Oxford University Press on behalf of The Genetics Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Background: Insect glutathione S-transferases (GSTs), a multifunctional protein family, play a crucial role in detoxification of plant defensive compounds. However, they have been rarely investigated in Sitodiplosis mosellana, a destructive pest of wheat worldwide. In this study, we characterized for the first time a delta (SmGSTd1) and two epsilon GST genes (SmGSTe1 and SmGSTe2) and analyzed their expression patterns and functions associated with adaptation to host plant defense in this species., Results: Expression of these SmGST genes greatly increased in S. mosellana larvae feeding on resistant wheat varieties Kenong1006, Shanmai139 and Jinmai47 which contain higher tannin and ferulic acid, the major defensive compounds of wheat against this pest, compared with those feeding on susceptible varieties Xinong822, Xinong88 and Xiaoyan22. Their expression was also tissue-specific, most predominant in larval midgut. Recombinant SmGSTs expressed in Escherichia coli could catalyze the conjugation of 1-chloro-2,4-dinitrobenzene, with activity peak at pH around 7.0 and temperature between 30 and 40 °C. Notably, they could metabolize tannin and ferulic acid, with the strongest metabolic ability by SmGSTe2 against two compounds, followed by SmGSTd1 on tannin, and SmGSTe1 on ferulic acid., Conclusion: The results suggest that these SmGSTs are important in metabolizing wheat defensive chemicals during feeding, which may be related to host plant adaptation of S. mosellana. Our study has provided information for future investigation and development of strategies such as host-induced gene silencing of insect-detoxifying genes for managing pest adaptation. © 2023 Society of Chemical Industry., (© 2023 Society of Chemical Industry.)

First Upper Triassic dipterans (Nematocera) are described based on isolated wings from Fuchsberg near Seinstedt (Sevatian, uppermost Norian of Lower Saxony, Germany): Crivoptychoptera nebrias gen. et sp. nov. (Psychodomorpha, Ptychopteridae), Ptychopteridae incertae sedis, Dohloboyia triassica gen. et sp. nov. (Bibionomorpha, Boholdoyidae) and Chironomidae incertae sedis (Culicomorpha). All taxa under discussion present the oldest occurrences of their families. Geological background and composition of the Upper Triassic insect fauna of Seinstedt are briefly discussed.

The paper presents very rare fossil record of crane flies. Inclusions in Baltic amber have documented the second evidence of the existence of the genus Tasiocera (Diptera: Limoniidae: Chioneinae) in ancient epochs of Earth's history. Hypotheses were also introduced regarding the environmental preferences of fossil Dasymolopilus in relation to modern representatives of the subgenus. The genus is numerous in species and widespread in the modern fauna, while only one species, Tasiocera (Dasymolophilus) circumcincta, has been known from the fossil record to date. The paper presents an additional description and graphic documentation of this species based on new materials. The discovery of two other species Tasiocera (Dasymolophilus) gorskii sp. nov. and Tasiocera (Dasymolophilus) baltica sp. nov. in Eocene resins documents the occurence of Tasiocera since Eocene. Interestingly, only subgenus Dasymolophilus is represented both in extinct and extant fauna while subgenus Tasiocera is not known from the fossil record. The new discovery is very significant, and the result of the study adds a brick to our understanding of the evolution of this group of insects and their habitat., (© 2024. The Author(s).)