Genetic relationships of three species of black flies (Diptera: Simuliidae) in Taiwan.

As an island about 150 km from the mainland, Taiwan would be expected to have endemic species. About 64 % of its 36 species of black flies are considered endemic, more than twice the level of endemicity that has been recorded for all insects on the island. To begin assessing the validity of the high level of endemism for the Simuliidae, we used giant chromosome banding patterns and cytochrome c oxidase I (COI) sequences, against a well-defined morphological backdrop, to evaluate three of Taiwan's black flies, Simulium chungi Takaoka & Huang, S. pingtungense Huang & Takaoka, and S. sakishimaense Takaoka. Molecular data revealed high similarity of populations of S. sakishimaense in Taiwan and at the type locality on Ishigaki Island, Japan, about 180 km to the east. Thus, populations referred to as S. sakishimaense in Taiwan are conspecific with typical S. sakishimaense in Japan, confirming their non-endemicity in Taiwan. Simulium sakishimaense might have reached Ishigaki by island hopping via Taiwan from the Chinese mainland. Chromosomes and the COI gene agree with morphology that S. sakishimaense is a member of the S. multistriatum species group although the chromosomal banding patterns do not indicate that it is distinct from S. fenestratum Edwards on the mainland. Although molecular sequences indicate S. sakishimaense is monophyletic, this taxon falls within the same Operational Taxonomic Unit as nine other members of the S. multistriatum group, including S. fenestratum. Simulium pingtungense, in agreement with morphology, is molecularly distinct from the 10 other analyzed members of the S. striatum species group, tentatively suggesting that it is endemic to Taiwan, pending analysis of samples from mainland China. Simulium chungi in Taiwan is chromosomally and molecularly unique, with larvae resembling those of S. saskishimaense. It is not, however, a member of either the S. multistriatum or S. striatum species groups. For now, the S. chungi species group remains a legitimate taxon consisting of two species. Strengthening the case for endemic taxa in Taiwan awaits analysis of key samples from the Chinese mainland.

Wild-caught adult black flies (Diptera: Simuliidae) from various ecological landscapes in Malaysia.

Most studies on black flies focus on the taxonomy and ecology of their aquatic stages. Despite posing a public health threat, the adults remain poorly studied in many countries, including Malaysia. The present study represents the first investigation of the distribution of wild-caught black flies from various ecological landscapes and climatic conditions in Malaysia. CO2-baited Malaise traps were set randomly at 41 sampling sites across Peninsular Malaysia from 2020 to 2023. In total, 532 black flies belonging to 14 species of four subgenera were captured. To ensure taxonomic rigor, specimens were identified to species morphologically and molecularly. The subgenus Gomphostilbia was the most abundant (71.43 %), followed by Simulium (14.28 %) and Davieselleum and Nevermannia each representing 7.14 % of the total captures. These species represented 14.74 % of the total species recorded from Malaysia. The most frequently collected species were Simulium roslihashimi (24.39 %), followed by S. aureohirtum, S. vanluni, and S. (Gomphostilbia) sp. 1 with 7.32 % each. The highest relative abundance was found for S. vanluni (86.09 %) and S. roslihashimi (7.14 %). Most species were found at elevation below 300 m (78.57 %); fewer were at elevation higher than 1,000 m (21.43 %). Two principal components accounted for 85.3 % of the total intersite variance. Simulium roslihashimi was found at almost every site, with a maximum relative humidity of 90 %. Simulium aureohirtum and S. vanluni were found at sites with relative humidity up to 73 %, but S. aureohirtum was found at higher temperatures (31 °C) compared with S. roslihashimi (28 °C) and S. vanluni (29 °C). The present study establishes the groundwork for further studies of wild adults in Malaysia and identifies the need to use more traps over the range of seasons and environmental conditions, particularly near breeding sites.

Flexural rigidity of hawkmoth antennae depends on the bending direction.

To probe its environment, the flying insect controllably flexes, twists, and maneuvers its antennae by coupling mechanical deformations with the sensory output. We question how the materials properties of insect antennae could influence their performance. A comparative study was conducted on four hawkmoth species: Manduca sexta, Ceratomia catalpae, Manduca quinquemaculata, and Xylophanes tersa. The morphology of the antennae of three hawkmoths that hover while feeding and one putatively non-nectar-feeding hawkmoth (Ceratomia catalpa) do not fundamentally differ, and all the antennae are comb-like (i.e., pectinate), markedly in males but weakly in females. Applying different weights to the free end of extracted cantilevered antennae, we discovered anisotropy in flexural rigidity when the antenna is forced to bend dorsally versus ventrally. The flexural rigidity of male antennae was less than that of females. Compared with the hawkmoths that hover while feeding, Ceratomia catalpae has almost two orders of magnitude lower flexural rigidity. Tensile tests showed that the stiffness of male and female antennae is almost the same. Therefore, the differences in flexural rigidity are explained by the distinct shapes of the antennal pectination. Like bristles in a comb, the pectinations provide extra rigidity to the antenna. We discuss the biological implications of these discoveries in relation to the flight habits of hawkmoths. Flexural anisotropy of antennae is expected in other groups of insects, but the targeted outcome may differ. Our work offers promising new applications of shaped fibers as mechanical sensors. STATEMENT OF SIGNIFICANCE: Insect antennae are blood-filled, segmented fibers with muscles in the two basal segments. The long terminal segment is muscle-free but can be flexed. Our comparative analysis of mechanical properties of hawkmoth antennae revealed a new feature: antenna resistance to bending depends on the bending direction. Our discovery replaces the conventional textbook scenario considering hawkmoth antennae as rigid rods. We showed that the pectinate antennae of hawkmoths behave as a comb in which the bristles resist bending when they come together. This anisotropy of flexural resistance offers a new mode of environmental sensing that has never been explored. The principles we found apply to other insects with non-axisymmetric antennae. Our work offers new applications for shaped fibers that could be designed to sense the flows.

Discovery of the Larvae and Pupae of the Black Fly Simulium (Gomphostilbia) khelangense and Breeding Habitats of Potential Pest Species of the S. (G.) chumpornense Subgroup (Simuliidae).

Two species of black flies (Simuliidae) in Thailand, Simulium chumpornense Takaoka and Kuvangkadilok, 2000, and S. khelangense Takaoka, Srisuka & Saeung, 2022, are potent vectors of avian blood protozoa of the genera Leucocytozoon and Trypanosoma and are pests of domestic avian species. Although the adults are abundant throughout Thailand, information on their breeding habitats is limited, and the immature stages of S. khelangense are unknown. We collected the larvae and pupae of S. khelangense from the Mekong River, the first-ever record of Simuliidae from this large continental river. Mitochondrial cytochrome c oxidase I and internal transcribed spacer 2 were used to associate the larvae and pupae with known adults. Both genetic markers strongly supported their identity as S. khelangense. The larvae and pupa of S. khelangense are described. The pupal gill filaments, larval abdominal protuberances, and setae distinguish this species from other members of the S. varicorne species group. The immature stages of S. chumpornense inhabit a wide variety of flowing waters, from small streams (3 m wide) to enormous continental rivers (400 m wide); thus, S. chumpornense is a habitat generalist. In contrast, S. khelangense was found only in the large Mekong River and is, therefore, a habitat specialist. Both species can exploit their principal habitats and produce abundant adult populations.

Molecular detection of blood protozoa and identification of black flies of the Simulium varicorne species group (Diptera: Simuliidae) in Thailand.

Species of the Simulium varicorne group in Thailand have veterinary significance as vectors of haemosporidian parasites. Accurate identification is, therefore, critical to the study of vectors and parasites. We used morphology and molecular markers to investigate cryptic genetic lineages in samples identified as Simulium chumpornense Takaoka & Kuvangkadilok, 2000. We also tested the efficiency of the nuclear internal transcribed spacer 2 (ITS2) marker for the identification of species in this group. Morphological examinations revealed that S. chumpornense lineage A is most similar to S. khelangense Takaoka, Srisuka & Saeung, 2022, with minor morphological differences. They are also genetically similar based on mitochondrial cytochrome c oxidase I (COI) sequences. Geographically, the sampling site where paratypes of S. khelangense were originally collected is <50 km from where S. chumpornense lineage A was collected. We concluded that cryptic lineage A of S. chumpornense is actually S. khelangense. COI sequences could not differentiate S. kuvangkadilokae Pramual and Tangkawanit, 2008 from S. chumpornense and S. khelangense. In contrast, ITS2 sequences provided perfect accuracy in the identification of these species. Molecular analyses of the blood protozoa Leucocytozoon and Trypanosoma demonstrated that S. khelangense carries L. shoutedeni, Leucocytozoon sp., and Trypanosoma avium. The Leucocytozoon sp. in S. khelangense differs genetically from that in S. asakoae Takaoka & Davies, 1995, signaling the possibility of vector-parasite specificity.

North African Endemism: A New Species of Black Fly (Diptera: Simuliidae) from the Djurdjura Mountains of Algeria.

Discoveries of endemic species highlight areas of biogeographic and conservation interest. Endemic species, however, are often morphologically disguised as more common and widespread species. The larval polytene chromosomes revealed a new species of black fly, Prosimulium fungiforme, from the Djurdjura Mountains of northern Algeria, and its female, male, pupa, and larva are described. The species is chromosomally unique; none of its 11 chromosomal rearrangements are shared with other species. Although the new species structurally resembles Prosimulium rufipes (Meigen) with which it previously has been confused, it can be distinguished from all other known species of Prosimulium in the Western Palearctic based on at least one character in each described life stage. Symbiotic organisms included two species of microsporidia, at least one of which is probably undescribed, one unknown protozoan pathogen novel in simuliids, and the trichomycete fungus Harpella melusinae Léger and Duboscq. Associated simuliid species included at least one new species of the genus Helodon. The new species of Prosimulium is tentatively considered endemic to the mountains of northern Algeria but might be expected in the mountains of eastern Morocco and northern Tunisia and perhaps in Sicily. If its endemic status holds, it would be the only nominal species of black fly unique to Algeria.

Integrated taxonomy of black flies (Diptera: Simuliidae) reveals unexpected diversity in the most arid ecosystem of Europe.

The family Simuliidae includes more than 2000 species of black flies worldwide. Their morphological uniformity creates difficulty for species identification, which limits our knowledge of their ecology and vectorial role. We investigated the systematics of black flies in a semi-arid area of the Iberian Peninsula, an ecologically harsh environment for these organisms. Sampling adult black flies in three different habitats (by means of CDC traps) and in avian nest boxes and collecting immature stages in high-salinity rills provided a representative sample of the component species. A combination of approaches, including morphological, chromosomal, and molecular (based on the mitochondrial cytochrome C oxidase subunit I (COI) and internal transcribed spacer 2 (ITS2) genes) revealed five species: four common species (Simulium intermedium, S. petricolum, S. pseudequinum, and S. rubzovianum) and the first European record for S. mellah. Barcoding gap and phylogenetic analyses revealed that ITS2 is a key marker to identify the species, whereas the COI marker does not provide enough resolution to identify some species or infer their phylogenetic relationships. Morphological and chromosomal features are also provided to identify S. mellah unequivocally. Our study highlights the need for integrated studies of black flies in ecologically extreme habitats to increase our knowledge of their distribution, ecology, and potential risks for public health.

First report of filarial nematodes in the genus Onchocerca infecting black flies (Diptera: Simuliidae) in Iran.

Black flies are blood-sucking insects of public health importance, and they are effective vectors of pathogens and parasites, such as filarial nematodes of the genus Onchocerca. Our previous surveys have shown that individuals of Simulium turgaicum are annoying pests of humans and livestock in the Aras River Basin of Iran. In the present study, adult black flies of S. turgaicum were trapped from different ecotopes of five villages in Khoda-Afarin County, Iran. By using a sensitive nested PCR assay and targeting the nuclear 18S rDNA-ITS1 marker, filarial infections were found in 38 (1.89%) of 2005 black flies. Homology exploration of 360 bp of the sequences indicated that the filarial worms are members of the family Onchocercidae, with maximum alignment scores of 93-95%. Phylogenetic analysis showed that two Iranian Onchocerca isolates were clustered in the O. fasciata-O. volvulus lineage and were well separated from other filarial nematodes. Both the entomological evidence (empty abdomen of the specimens) and climatologic data (adequate accumulated degree days for development) suggest that the filarial DNA was probably that of infective larvae of vertebrates. This is the first report of an infection by Onchocerca species in S. turgaicum and the first record of onchocercids in black flies in Iran; however, more research is required to demonstrate transmission of these filarial worms by black flies in nature.

Wettability and morphology of proboscises interweave with hawkmoth evolutionary history.

Hovering hawkmoths expend significant energy while feeding, which should select for greater feeding efficiency. Although increased feeding efficiency has been implicitly assumed, it has never been assessed. We hypothesized that hawkmoths have proboscises specialized for gathering nectar passively. Using contact angle and capillary pressure to evaluate capillary action of the proboscis, we conducted a comparative analysis of wetting and absorption properties for 13 species of hawkmoths. We showed that all 13 species have a hydrophilic proboscis. In contradistinction, the proboscises of all other tested lepidopteran species have a wetting dichotomy with only the distal ∼10% hydrophilic. Longer proboscises are more wettable, suggesting that species of hawkmoths with long proboscises are more efficient at acquiring nectar by the proboscis surface than are species with shorter proboscises. All hawkmoth species also show strong capillary pressure, which, together with the feeding behaviors we observed, ensures that nectar will be delivered to the food canal efficiently. The patterns we found suggest that different subfamilies of hawkmoths use different feeding strategies. Our comparative approach reveals that hawkmoths are unique among Lepidoptera and highlights the importance of considering the physical characteristics of the proboscis to understand the evolution and diversification of hawkmoths.

From bites to barcodes: uncovering the hidden diversity of black flies (Diptera: Simuliidae) in Vietnam.

BACKGROUND: Prompt and precise identification of black flies (Simuliidae) is crucial, given their biting behaviour and significant impact on human and animal health. To address the challenges presented by morphology and chromosomes in black fly taxonomy, along with the limited availability of molecular data pertaining to the black fly fauna in Vietnam, this study employed DNA-based approaches. Specifically, we used mitochondrial and nuclear-encoded genes to distinguish nominal species of black flies in Vietnam. METHODS: In this study, 135 mitochondrial cytochrome c oxidase subunit I (COI) sequences were established for 45 species in the genus Simulium in Vietnam, encompassing three subgenera (Gomphostilbia, Nevermannia, and Simulium), with 64 paratypes of 27 species and 16 topotypes of six species. Of these COI sequences, 71, representing 27 species, are reported for the first time. RESULTS: Combined with GenBank sequences of specimens from Malaysia, Myanmar, Thailand, and Vietnam, a total of 234 DNA barcodes of 53 nominal species resulted in a 71% success rate for species identification. Species from the non-monophyletic Simulium asakoae, S. feuerborni, S. multistriatum, S. striatum, S. tuberosum, and S. variegatum species groups were associated with ambiguous or incorrect identifications. Pairwise distances, phylogenetics, and species delimitation analyses revealed a high level of cryptic diversity, with discovery of 15 cryptic taxa. The current study also revealed the limited utility of a fast-evolving nuclear gene, big zinc finger (BZF), in discriminating closely related, morphologically similar nominal species of the S. asakoae species group. CONCLUSION: This study represents the first comprehensive molecular genetic analysis of the black fly fauna in Vietnam to our knowledge, providing a foundation for future research. DNA barcoding exhibits varying levels of differentiating efficiency across species groups but is valuable in the discovery of cryptic diversity.

DNA barcoding of black flies (Diptera: Simuliidae) in Indonesia.

BACKGROUND: DNA barcoding is a valuable taxonomic tool for rapid and accurate species identification and cryptic species discovery in black flies. Indonesia has 143 nominal species of black flies, but information on their biological aspects, including vectorial capacity and biting habits, remains underreported, in part because of identification problems. The current study represents the first comprehensive DNA barcoding of Indonesian black flies using mitochondrial cytochrome c oxidase subunit I (COI) gene sequences. METHODS: Genomic DNA of Indonesian black fly samples were extracted and sequenced, producing 86 COI sequences in total. Two hundred four COI sequences, including 118 GenBank sequences, were analysed. Maximum likelihood (ML) and Bayesian inference (BI) trees were constructed and species delimitation analyses, including ASAP, GMYC and single PTP, were performed to determine whether the species of Indonesian black flies could be delineated. Intra- and interspecific genetic distances were also calculated and the efficacy of COI sequences for species identification was tested. RESULTS: The DNA barcodes successfully distinguished most morphologically distinct species (> 80% of sampled taxa). Nonetheless, high maximum intraspecific distances (3.32-13.94%) in 11 species suggested cryptic diversity. Notably, populations of the common taxa Simulium (Gomphostilbia) cheongi, S. (Gomphostilbia) sheilae, S. (Nevermannia) feuerborni and S. (Simulium) tani in the islands of Indonesia were genetically distinct from those on the Southeast Asian mainland (Malaysia and Thailand). Integrated morphological, cytogenetic and nuclear DNA studies are warranted to clarify the taxonomic status of these more complex taxa. CONCLUSIONS: The findings showed that COI barcoding is a promising taxonomic tool for Indonesian black flies. The DNA barcodes will aid in correct identification and genetic study of Indonesian black flies, which will be helpful in the control and management of potential vector species.

Fast-evolving nuclear genes as barcoding markers for black flies (Diptera: Simuliidae) in Thailand.

Rapid and accurate identification is a prerequisite for the study of all aspects of species, particularly for pests and vectors. Black flies are economically significant blood-sucking insects, as many species are pests and vectors that transmit parasites to humans and other animals. We examined the efficiency of two fast-evolving nuclear genes, elongator complex protein 1 (ECP1) and big zinc finger (BZF), for identifying 13 nominal species in three species-groups of black flies, the Simulium multistriatum, S. striatum, and S. tuberosum groups, in Thailand where the mitochondrial cytochrome c oxidase I (COI) gene has not been successful for differentiating many nominal species. ECP1 gene sequences were highly effective for identification, with >96% (181 of 188) of the specimens correctly identified. Unsuccessful identifications based on ECP1 were between S. nakhonense and S. chiangmaiense, which are members of the S. striatum species-group, whereas all identifications of nominal species of the S. multistriatum and S. tuberosum species-groups were successful. In contrast, BZF had successful rates for the S. striatum species-group, with >93% (71 of 76) of the specimens correctly identified. This gene also successfully assigned unknown larvae of the S. striatum group to species. Phylogenetic analyses and molecular species delimitations based on the BZF gene uncovered cryptic diversity in two nominal species, S. nakhonense and S. wangkwaiense, which will require resolution through further study.

Haemolymph viscosity in hawkmoths and its implications for hovering flight.

Viscosity determines the resistance of haemolymph flow through the insect body. For flying insects, viscosity is a major physiological parameter limiting flight performance by controlling the flow rate of fuel to the flight muscles, circulating nutrients and rapidly removing metabolic waste products. The more viscous the haemolymph, the greater the metabolic energy needed to pump it through confined spaces. By employing magnetic rotational spectroscopy with nickel nanorods, we showed that viscosity of haemolymph in resting hawkmoths (Sphingidae) depends on wing size non-monotonically. Viscosity increases for small hawkmoths with high wingbeat frequencies, reaches a maximum for middle-sized hawkmoths with moderate wingbeat frequencies, and decreases in large hawkmoths with slower wingbeat frequencies but greater lift. Accordingly, hawkmoths with small and large wings have viscosities approaching that of water, whereas hawkmoths with mid-sized wings have more than twofold greater viscosity. The metabolic demands of flight correlate with significant changes in circulatory strategies via modulation of haemolymph viscosity. Thus, the evolution of hovering flight would require fine-tuned viscosity adjustments to balance the need for the haemolymph to carry more fuel to the flight muscles while decreasing the viscous dissipation associated with its circulation.

Chromosomes as Barcodes: Discovery of a New Species of Black Fly (Diptera: Simuliidae) from California, USA.

One of the most popular tools for species discovery and resolution is the DNA barcode, typically based on the cytochrome c oxidase I (COI) gene. However, other non-genic barcodes are available for Diptera. The banding sequence of polytene chromosomes in some dipteran cells, particularly of the larval silk glands, can provide a unique species barcode. We used the sequence of bands to reveal a new species of black fly in the Simulium (Boreosimulium) annulus species group from California, USA. To further characterize the species and provide more integrated taxonomy, we morphologically described all life stages above the egg, formally named the species Simulium ustulatum n. sp., and provided a conventional COI barcode. The COI barcode confirmed the chromosomal and morphological evidence that the species is a new member of the S. annulus group, and enabled identification of the larva and female, which are structurally similar to those of other species. The chromosomal barcode shows that this species has the most rearranged complement, compared with the eight other North American members of its species group, with up to 12 times the number of fixed rearrangements. Up to six chromosomal rearrangements, including autosomal polymorphisms and sex-linked phenomena, are shared with other members of the group. The most unique and conspicuous chromosomal feature of this new species is a large, pale-staining chromocenter from which the six chromosomal arms radiate. The distribution of this univoltine species in lowland rivers of California's Central Valley could make it vulnerable, given climate change and increasing land development.

Insect antennae: Coupling blood pressure with cuticle deformation to control movement.

Insect antennae are hollow, blood-filled fibers with complex shape. Muscles in the two basal segments control antennal movement, but the rest (flagellum) is muscle-free. The insect can controllably flex, twist, and maneuver its antennae laterally. To explain this behavior, we performed a comparative study of structural and tensile properties of the antennae of Periplaneta americana (American cockroach), Manduca sexta (Carolina hawkmoth), and Vanessa cardui (painted lady butterfly). These antennae demonstrate a range of distinguishable tensile properties, responding either as brittle or strain-adaptive fibers that stiffen when stretched. Scanning electron microscopy and high-speed imaging of antennal breakup during stretching revealed complex coupling of blood pressure and cuticle deformation in antennae. A generalized Lamé theory of solid mechanics was developed to include the force-driven deformation of blood-filled antennal tubes. We validated the theory against experiments with artificial antennae with no adjustable parameters. Blood pressure increased when the insect inflated its antennae or decreased below ambient pressure when an external tensile load was applied to the antenna. The pressure-cuticle coupling can be controlled through changes of the blood volume in the antennal lumen. In insects that do not fill the antennal lumen with blood, this blood pressure control is lacking, and the antennae react only by muscular activation. We suggest that the principles we have discovered for insect antennae apply to other appendages that share a leg-derived ancestry. Our work offers promising new applications for multifunctional fiber-based microfluidics that could transport fluids and be manipulated by the same fluid on demand. STATEMENT OF SIGNIFICANCE: Insect antennae are blood-filled, segmented fibers with muscles in the two basal segments. The long terminal segment is muscle-free but can be flexed. To explain this behavior, we examined structure-function relationships of antennae of cockroaches, hawkmoths, and butterflies. Hawkmoth antennae behaved as brittle fibers, but butterfly and cockroach antennae showed strain-adaptive behavior like fibers that stiffen when stretched. Videomicroscopy of antennal breakup during stretching revealed complex coupling of blood pressure and cuticle deformation. Our solid mechanics model explains this behavior. Because antennae are leg-derived appendages, we suggest that the principles we found apply to other appendages of leg-derived ancestry. Our work offers new applications for multifunctional fiber-based microfluidics that could transport fluids and be manipulated by the fluid on demand.

Natural infections and distributions of parasitic mermithids (Nematoda: Mermithidae) infecting larval black flies (Diptera: Simuliidae) in tropical streams of Malaysia.

Mermithids are parasites of black flies that cause host mortality along with physical and behavioural changes in infected hosts. However, there is a lack of knowledge on the distribution of mermithids infecting black fly larvae and the factors that influence these distributions in Asia, including Malaysia. A total of 13,116 mid- to late-instar black fly larvae belonging to 42 species were collected from 138 streams across East and West Malaysia and screened for the presence of mermithid parasites. Overall, 121 mermithids were obtained from 107 (0.82%) larvae of nine (21.4%) black fly species. The average number of mermithids per black fly host was 1.10 ± 0.04 (SE), ranging from one to three mermithids per host. Mermithid infection was highest in Simulium trangense, with a frequency of occurrence of 6.5%, followed by S. cheongi (5.8%) and S. angulistylum complex (2.9%). Infection was lowest in S. brevipar and S. tahanense, with a frequency of occurrence of 0.7% each. Regression analysis indicated that mermithid infections in larval black flies were significantly associated with cooler and shallower streams with more canopy cover, dense riparian vegetation, high dissolved oxygen, and lower conductivity and complete pH. Forward logistic regression further indicated that infections in S. cheongi were associated with shaded, cooler, slightly acidic streams with higher conductivity and dissolved oxygen. These findings suggest that mermithid infections in larval black flies in Malaysia are not randomly distributed and are influenced by the breeding habitat of their hosts.

A new species in the Simulium vernum group from the Northern Limestone Alps of Austria: Simulium hasekei (Diptera: Simuliidae).

Simulium hasekei new species is described from the Alps of Austria. It is characterized by a broad trapezoidal ventral plate in the male, long straight arms of the genital fork in the female, a well-developed anterodorsal projection on the weakly woven cocoon, and a deep rounded postgenal cleft and strong paralateral hypostomal teeth in the larva. The species is chromosomally most similar to the Holarctic S. bicorne Dorogostaisky, Rubtsov Vlasenko and S. fontinale Radzivilovskaya and the Nearctic S. craigi Adler Currie. It is known from one small ponor brook, in association with S. aureum (Fries) s. s., S. beltukovae (Rubtsov), and Simulium vernum Macquart s. s.

Morphological and genetic revision of cytoform 'L' of the Simulium (Simulium) tani complex from Taiwan, and cytoform 'D' of the S. (S.) suzukii complex (Diptera: Simuliidae) from the Nansei Islands, Japan.

The species status of two cytoforms of two species complexes in the Simulium (Simulium) tuberosum species-group, which are almost indistinguishable in the pupal stage, was morphologically and genetically evaluated. Cytoform 'L' of the S. (S.) tani Takaoka & Davies complex, previously recognized as S. (S.) suzukii Rubtsov in Taiwan, is described as a new species, S. (S.) jianshiense. It is morphologically distinguishable as adults from two members of the S. (S.) suzukii complex: cytoform 'C' from Hokkaido, selected to represent the type of S. (S.) suzukii sensu stricto, and cytoform 'D' from Okinawa Island and, based on our chromosomal analysis, also from Amami Island. This new species is genetically separated from both cytoforms of the S. (S.) suzukii complex with a genetic distance of 5.31-6.67%. Cytoform 'D' is distinguished from cytoform 'C' by the color of the male forecoxa and relative length of the female sensory vesicle to the third maxillary palpomere. Accordingly, the name S. (S.) ryukyuense Ogata, once regarded as a synonym of S. (S.) suzukii, is revalidated and applied to cytoform 'D'. The genetic distance between S. (S.) ryukyuense and S. (S.) suzukii sensu stricto is 1.24-1.60%.

Chromosomal and Molecular Diversity in the Simulium ornatum Group (Diptera: Simuliidae) in the Western Tian Shan Range of Central Asia.

By any measure, such as abundance, species diversity or geographic range, the Simulium ornatum species group is one of the most successful Palearctic taxa of black flies. To explore potential diversity in this group in the Tian Shan range of Central Asia, we focused on Kyrgyzstan, in which three nominal morphospecies have been recorded. Among our samples, we morphologically identified S. mesasiaticum Rubtsov and a second possible species tentatively identified as S. ferganicum Rubtsov. By analyzing banding patterns of the larval polytene chromosomes, we discovered two fixed inversions, two sex-linked rearrangements, and 19 autosomal rearrangements, including supernumerary B chromosomes. The chromosomal data indicate minimal diversity of only one or two species across the surveyed area of nearly 50,000 km2. Mitochondrial DNA (CO1) sequences fell into three distinct clusters, possibly representing separate species. The chromosomal, molecular, and morphological data indicate that Kyrgyz populations are unique within the S. ornatum group, but the data sets are not entirely congruent. Thus, reconciling data sets and assigning existing names is tentative. Simulium mesasiaticum is linked with undifferentiated sex chromosomes, one of the three CO1 clades, and higher elevations, whereas S. ferganicum is tenuously associated with differentiated sex chromosomes, a separate CO1 clade, and lower elevations. These associations leave one Kyrgyz larva, which is in a third CO1 clade, unlinked to a formal species name. Our analyses also indicate that S. ornatum Meigen sensu stricto, contrary to previous reports, does not occur in Kyrgyzstan and should be deleted from the country's faunal list.

Elastocapillary effect in self-repair of proboscises of butterflies and moths.

HYPOTHESIS: Self-repair in living organisms, without tissue regeneration or regrowth, is rare. Recent discovery that butterflies can self-repair the proboscis after the two halves (galeae) have been separated raised a question about the physical mechanism allowing them to reunite the parts. We discovered that butterflies pump saliva during repair of their proboscises. We then hypothesized that saliva spreading along the food canal of the proboscis would create capillary forces capable of bringing the galeae together. EXPERIMENT: To test the hypothesis, we distinguished capillary forces from muscular action of the galeae by sedating butterflies and video tracking retraction of the saliva menisci during galeal separation. To theoretically show capillary adhesion, the elastic moduli of the galeae were measured, and the galeal profiles were extracted from videos as a function of time. The values were then fitted with a mathematical model based on an augmented Euler-Bernoulli beam theory whereby each galea was treated as a beam bent by capillary forces due to saliva. We also evaluated friction forces that prevented disjoining of the galea at the tip of their separation. FINDINGS: The results showed that butterflies use saliva to repair their proboscises via capillary adhesion, and theoretically supported the role of saliva in providing the necessary capillary forces to bring the galeae together. Tangential shear forces acting parallel to the galea at the tip of their separation are caused primarily by friction between the cuticular linking structures.