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The taxonomy of Merodon dobrogensis Bradescu, 1982 (Diptera: Syrphidae) species subgroup was reviewed. Multiple data sources (morphology, geometric morphometry of wings and surstylus, molecular data, and distributional data) were used to investigate the species subgroup in the manner of integrative taxonomy. Merodon dobrogensis Bradescu, 1982 and M. puniceus Vujić, Radenković, and Pérez-Bañón, 2011 are supported as distinct species belonging to the M. dobrogensis species complex within the M. dobrogensis species subgroup. Additionally, evidence is presented for the description of a new species, M. rojoi Radenković and Vujić new species , with a distribution in mainland Greece, the Greek island Euboea, and the Peloponnese. A short diagnosis is provided for the M. aureus species group, the M. dobrogensis species subgroup, and the newly defined M. dobrogensis species complex, in addition to a description of the new species, with drawings and photographs of adult morphology. [ABSTRACT FROM AUTHOR]

Quantitative genetics aims at untangling the genetic and environmental effects on phenotypic variation. Trait heritability, which summarizes the relative importance of genetic effects, is estimated at the intraspecific level, but theory predicts that heritability could influence long-term evolution of quantitative traits. The phylogenetic signal concept bears resemblance to heritability and it has often been called species-level heritability. Under certain conditions, such as trait neutrality or contribution to phylogenesis, within-species heritability and between-species phylogenetic signal should be correlated. Here, we investigate the potential relationship between these two concepts by examining the evolution of multiple morphological traits for which heritability has been estimated in Drosophila melanogaster. Specifically, we analysed 42 morphological traits in both sexes on a phylogeny inferred from 22 nuclear genes for nine species of the melanogaster subgroup. We used Pagel's λ as a measurement of phylogenetic signal because it is the least influenced by the number of analysed taxa. Pigmentation traits showed the strongest concordance with the phylogeny, but no correlation was found between phylogenetic signal and heritability estimates mined from the literature. We obtained data for multiple climatic variables inferred from the geographical distribution of each species. Phylogenetic regression of quantitative traits on climatic variables showed a significantly positive correlation with heritability. Convergent selection, the response to which depends on the trait heritability, may have led to the null association between phylogenetic signal and heritability for morphological traits in Drosophila. We discuss the possible causes of discrepancy between both statistics and caution against their confusion in evolutionary biology. [ABSTRACT FROM AUTHOR]

The Aleiodes bakeri (Brues) species subgroup of the A. seriatus species group is defined based on two previously described species, A. bakeri and A. nigristemmaticum (Enderlein), and is greatly expanded in this paper with an identification key, descriptions, and illustrations of 18 new species from the Neotropical Region: A. andinus Shaw & Shimbori, sp. nov.; angustus Shimbori & Shaw, sp. nov.; asenjoi Shimbori & Shaw, sp. nov.; bahiensis Shimbori & Shaw, sp. nov.; barrosi Shimbori & Shaw, sp. nov.; brevicarina Shimbori & Shaw, sp. nov.; coariensis Shimbori & Shaw, sp. nov.; goiasensis Shimbori & Shaw, sp. nov.; gonodontivorus Shaw & Shimbori, sp. nov.; hyalinus Shimbori & Shaw, sp. nov.; inga Shimbori & Shaw, sp. nov.; joaquimi Shimbori & Shaw, sp. nov.; lidiae Shimbori & Shaw, sp. nov.; mabelae Shimbori & Shaw, sp. nov.; maculosus Shimbori & Shaw, sp. nov.; ovatus Shimbori & Shaw, sp. nov.; santarosensis Shaw & Shimbori, sp. nov.; and taurus Shimbori & Penteado-Dias, sp. nov. It is hypothesized that the A. bakeri species subgroup is a monophyletic lineage within the larger and probably artificial A. seriatus species group (those Aleiodes with a comb of flat setae at the apex of the hind tibia), and can be distinguished from other members of the seriatus group by having the hind wing vein r present, although weakly indicated; the hind wing marginal cell suddenly widened at junction of veins RS and r; the subbasal cell of the fore wing mostly glabrous but often with two rows of short setae subapically; glabrous regions of the wings also commonly found in the first subdiscal, discal, and basal cells of the fore wing, and the basal cell of hind wing; ocelli quite large, with the width of a lateral ocellus being distinctly larger than the ocellarocular distance; and being relatively large Aleiodes species with body almost entirely brownish yellow or reddish brown. In addition, a new replacement name, Aleiodes buntikae Shimbori & Shaw, nom. nov., is proposed for the species formerly called Aleiodes (Hemigyroneuron) bakeri Butcher & Quicke, 2011. [ABSTRACT FROM AUTHOR]

Introgression, the exchange of alleles between species, is a common event in nature. This transfer of alleles between species must happen through fertile hybrids. Characterizing the traits that cause defects in hybrids illuminates how and when gene flow is expected to occur. Inviability and sterility are extreme examples of fitness reductions but are not the only type of defects in hybrids. Some traits specific to hybrids are more subtle but are important to determine their fitness. In this report, we study whether F1 hybrids between two species pairs of Drosophila are as attractive as the parental species. We find that in both species pairs, the sexual attractiveness of the F1 hybrids is reduced and that pure species discriminate strongly against them. We also find that the cuticular hydrocarbon (CHC) profile of the female hybrids is intermediate between the parental species. Perfuming experiments show that modifying the CHC profile of the female hybrids to resemble pure species improves their chances of mating. Our results show that behavioral discrimination against hybrids might be an important component of the persistence of species that can hybridize. [ABSTRACT FROM AUTHOR]

Leptus (Leptus) hajiqanbari sp. nov. (Acari: Erythraeidae), detached from unknown Noctuidae (Insecta: Lepidoptera) from Jahrom City, Fars Province, Iran, is described and illustrated based on the larva. This species belongs to the anomalus species group and iguacuicus species subgroup which can be identified based on the characters as follows: Palpal femur with one seta, palpal genu with two setae, four setae between coxae II and III and sensillary setae setulose throughout the length. A key to species of iguacuicus species subgroup is presented. [ABSTRACT FROM AUTHOR]

Heat‐shock (HS) assays to understand the connection between standing inversion variation and evolutionary response to climate change in Drosophila subobscura found that "warm‐climate" inversion O3+4 exhibits non‐HS levels of Hsp70 protein like those of "cold‐climate" OST after HS induction. This was unexpected, as overexpression of Hsp70 can incur multiple fitness costs. To understand the genetic basis of this finding, we have determined the genomic sequence organization of the Hsp70 family in four different inversions, including OST, O3+4, O3+4+8 and O3+4+16, using as outgroups the remainder of the subobscura species subgroup, namely Drosophila madeirensis and Drosophila guanche. We found (i) in all the assayed lines, the Hsp70 family resides in cytological locus 94A and consists of only two genes, each with four HS elements (HSEs) and three GAGA sites on its promoter. Yet, in OST, the family is comparatively more compact; (ii) the two Hsp70 copies evolve in concert through gene conversion, except in D. guanche; (iii) within D. subobscura, the rate of concerted evolution is strongly structured by inversion, being higher in OST than in O3+4; and (iv) in D. guanche, the two copies accumulated multiple differences, including a newly evolved "gap‐type" HSE2. The absence of concerted evolution in this species may be related to a long‐gone‐unnoticed observation that it lacks Hsp70 HS response, perhaps because it has evolved within a narrow thermal range in an oceanic island. Our results point to a previously unrealized link between inversions and concerted evolution, with potentially major implications for understanding genome evolution. [ABSTRACT FROM AUTHOR]

Eumerus Meigen (Diptera, Syrphidae) is one of the most speciose hoverfly genera in Europe, with several species groups recognized within. As part of the tricolor group of species, a subgroup of long-legged representatives stands out. We name it Eumerus binominatus subgroup and provide descriptions for two new European species which belong to this subgroup: E. grallator sp. nov. from mainland Spain and E. tenuitarsis sp. nov. from Lesvos and Evros, Greece. A key for all five recognized species of the binominatus subgroup is provided. [ABSTRACT FROM AUTHOR]

To investigate the phylogenetic relationships and molecular evolution of α-amylase (Amy) genes in the Drosophila montium species subgroup, we constructed the phylogenetic tree of the Amy genes from 40 species from the montium subgroup. On our tree the sequences of the auraria, kikkawai, and jambulina complexes formed distinct tight clusters. However, there were a few inconsistencies between the clustering pattern of the sequences and taxonomic classification in the kikkawai and jambulina complexes. Sequences of species from other complexes (bocqueti, bakoue, nikananu, and serrata) often did not cluster with their respective taxonomic groups. This suggests that relationships among the Amy genes may be different from those among species due to their particular evolution. Alternatively, the current taxonomy of the investigated species is unreliable. Two types of divergent paralogous Amy genes, the so-called Amy1- and Amy3-type genes, previously identified in the D. kikkawai complex, were common in the montium subgroup, suggesting that the duplication event from which these genes originate is as ancient as the subgroup or it could even predate its differentiation. Thc Amy1-type genes were closer to the Amy genes of D. melanogaster and D. pseudoobscura than to the Amy3-type genes. In the Amy1-type genes, the loss of the ancestral intron occurred independently in the auraria complex and in several Afrotropical species. The GC content at synonymous third codon positions (GC3s) of the Amy1-type genes was higher than that of the Amy3-type genes. Furthermore, the Amy1-type genes had more biased codon usage than the Amy3-type genes. The correlations between GC3s and GC content in the introns (GCi) differed between these two Amy-type genes. These findings suggest that the evolutionary forces that have affected silent sites of the two Amy-type genes in the montium species subgroup may differ. [ABSTRACT FROM AUTHOR]

Although molecular and phenotypic evolution have been studied extensively in Drosophila melanogaster and its close relatives, phylogenetic relationships within the D. melanogaster species subgroup remain unresolved. In particular, recent molecular studies have not converged on the branching orders of the D. yakuba–D. teissieri and D. erecta–D. orena species pairs relative to the D. melanogaster–D. simulans–D. mauritiana–D. sechellia species complex. Here, we reconstruct the phylogeny of the melanogaster species subgroup using DNA sequence data from four nuclear genes. We have employed “vectorette PCR” to obtain sequence data for orthologous regions of the Alcohol dehydrogenase (Adh), Alcohol dehydrogenase related (Adhr), Glucose dehydrogenase (Gld), and rosy (ry) genes (totaling 7164 bp) from six melanogaster subgroup species (D. melanogaster, D. simulans, D. teissieri, D. yakuba, D. erecta, and D. orena) and three species from subgroups outside the melanogaster species subgroup [D. eugracilis (eugracilis subgroup), D. mimetica (suzukii subgroup), and D. lutescens (takahashii subgroup)]. Relationships within the D. simulans complex are not addressed. Phylogenetic analyses employing maximum parsimony, neighbor-joining, and maximum likelihood methods strongly support a D. yakuba–D. teissieri and D. erecta–D. orena clade within the melanogaster species subgroup. D. eugracilis is grouped closer to the melanogaster subgroup than a D. mimetica–D. lutescens clade. This tree topology is supported by reconstructions employing simple (single parameter) and more complex (nonreversible) substitution models. [ABSTRACT FROM AUTHOR]

Genes involved in male fertility are potential targets for sexual selection, and their evolution may play a role in reproductive isolation and speciation. Here we describe a new Drosophila melanogaster gene, ocnus (ocn), that encodes a protein abundant in testes nuclear extracts. RT-PCR indicates that ocn transcription is limited to males and is specific to testes. ocn shares homology with another testis-specific gene, janusB (janB), and is located just distal to janB on chromosome 3. The two genes also share homology with the adjacent janusA (janA) gene, suggesting that multiple duplication events have occurred within this region of the genome. We cloned and sequenced these three genes from species of the D. melanogaster species subgroup. Phylogenetic analysis based on protein-encoding sequences predicts a duplication pattern of janA → janA janB → janA janB ocn, with the latter event occurring after the divergence of the D. melanogaster and Drosophila obscura species groups. We found significant heterogeneity in the rates of evolution among the three genes within the D. melanogaster species subgroup as measured by the ratio of nonsynonymous to synonymous substitutions, suggesting that diversification of gene function followed each duplication event and that each gene evolved under different selective constraints. All three genes showed faster rates of evolution than genes encoding proteins with metabolic function. These results are consistent with previous studies that have detected an increased rate of evolution in genes with reproductive function. [ABSTRACT FROM PUBLISHER]

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The polytene chromosomes of two new species of Drosophila, D. sechellia and D. orena, both members of the melanogaster species subgroup, are described. The chromosomes of D. sechellia, a species endemic to certain islands in the Seychelles, are homosequential with those of D. simulans and D. mauritiana. The chromosomes of D. orena, a species from the mountains of west Africa, are very similar to those of D. erecta. We discuss the interrelationships of the eight known species of the melanogaster species subgroup, based upon an analysis of their chromosome banding patterns. [ABSTRACT FROM AUTHOR]

We determined the nucleotide sequences of two regions in the A+T-rich region of mitochondrial DNA (mtDNA) in the siI and siII types of D. simulans, the maII type of D. mauritiana, and D. sechellia. The sequences were aligned with those of the corresponding regions of siIII of D. simulans and maI of D. mauritiana, D. melanogaster, and D. yakuba. The type I and type II elements and the T-stretches were detected in all eight of the mtDNA types compared, indicating that the three elements are essential in the A+T-rich region of this species subgroup. The alignment revealed several short repetitive sequences and relatively large deletions in the central portions of the region. In the highly conserved sequence elements in the type II elements, the substitution rates were not uniform among lineages and acceleration in the substitution rate might have been due to loss of functional constraint in the stem–loop-forming sequences predicted in the type II elements. Patterns of nucleotide substitutions observed in the A+T-rich region were further compared with those in the coding regions and in the intergenic regions of mtDNA. Substitutions between A and T were particularly repressed in the highly conserved sequence elements and in the intergenic regions compared with those in the A+T-rich region excluding the highly conserved sequence elements and in the fourfold degenerate sites in the coding regions. The functional and structural characteristics of the A+T-rich region that might be involved in this substitutional bias are discussed. [ABSTRACT FROM AUTHOR]

The Odysseus ( OdsH) gene was duplicated from its ancestral neuron-expressed gene, unc-4, and then evolved very rapidly under strong positive Darwinian selection as a speciation gene causing hybrid-male sterility between closely related species of the Drosophila simulans clade. Has OdsH also experienced similar positive selection between Drosophila sibling species other than those of the simulans clade? We cloned and sequenced OdsH and unc-4 from two clades of the Drosophila montium species subgroup, the Drosophila lini and the Drosophila kikkawai clades. The ratios of Ka/Ks for OdsH were remarkably low between sibling species of these two clades, suggesting that OdsH has been subjected to strong purifying selection in these two clades. [ABSTRACT FROM AUTHOR]

Molecular domestication of a transposable element is defined as its functional recruitment by the host genome. To date, two independent events of molecular domestication of the P transposable element have been described: in the Drosophila obscura species group and in the Drosophila montium species subgroup. These P neogenes consist of stationary, nonrepeated sequences, potentially encoding 66-kDa repressor-like (RL) proteins. Here we investigate the function of the montium P neogenes. We provide evidence for the presence of RL proteins in two montium species ( D. tsacasi and D. bocqueti) specifically expressed in adult and larval brain and gonads. We tested the hypothesis that the montium P neogenes’ function is related to the repression of the transposition of distantly related mobile P elements which coexist in the genome. Our results strongly suggest that the montium P neogenes are not recruited to downregulate the P element transposition. Given that all the proteins encoded by mobile or stationary P homologous sequences show a strong conservation of the DNA binding domain, we tested the capacity of the RL proteins to bind DNA in vivo. Immunostaining of polytene chromosomes in D. melanogaster transgenic lines strongly suggests that montium P neogenes encode proteins that bind DNA in vivo. RL proteins show multiple binding to the chromosomes. We suggest that the property recruited in the case of the montium P neoproteins is their DNA binding property. The possible functions of these neogenes are discussed. [ABSTRACT FROM AUTHOR]

We have analyzed ∼18 kb of DNA in and upstream of the defective chorion-1 (dec-1) locus of the eight known species of the melanogaster species subgroup of Drosophila. The restriction maps of D. simulans, D. mauritiana, D. sechellia, D. erecta, and D. orena are shown to have basically the restriction map of D. melanogaster, whereas the maps of D. teissieri and D. yakuba were more difficult to align. However, the basic amount of DNA and sequence arrangement appear to have been conserved in these species. A small deletion of varying length (65-200 bp) is found in a repeated sequence of the central transcribed region of D. melanogaster, D. simulans, and D. erecta. Restriction site mapping indicated that the dec-1 gene is highly conserved in the melanogaster species subgroup. However, sequence comparison revealed that the amount of nucleotide and amino acid substitution in the repeated region is much larger than in the 5′ translated region. The 5′ flanking region showed noticeable restriction site polymorphisms between species. Based on calculations from the restriction maps a dendrogram was derived that supports earlier published phylogenetic relationships within the melanogaster species subgroup except that the erecta-orena pair is placed closer to the melanogaster complex than to D. teissieri and D. yakuba. [ABSTRACT FROM AUTHOR]

Detailed restriction maps (40 cleavage sites on average) of mitochondrial DNAs (mtDNAs) from the eight species of the melanogaster species subgroup of Drosophila were established. Comparison of the cleavage sites allowed us to build a phylogenetic tree based on the matrix of nucleotide distances and to select the most parsimonious network. The two methods led to similar results, which were compared with those in the literature obtained from nuclear characters. The three chromosomally homosequential species D. simulans, D. mauritiana, and D. sechellia are mitochondrially very related, but exhibit complex phylogenetic relationships. D. melanogaster is their closest relative, and the four species form a monophyletic group (the D. melanogaster complex), which is confirmed by the shared unusual length of their mt genomes (18-19 kb). The other four species of the subgroup ( D. yakuba, D. teissieri, D. erecta, and D. orena) are characterized by a much shorter mt genome (16-16.5 kb). The monophyletic character of the D. yakuba complex, however, is questionable. Two species of this complex, D. yakuba and D. teissieri, are mitochondrially indistinguishable (at the level of our investigation) in spite of their noticeable allozymic and chromosomal divergence. Finally, mtDNA distances were compared with the nuclear-DNA distances thus far established. These sequences seem to evolve at rather similar rates, the mtDNA rate being barely double that of nuclear DNA. [ABSTRACT FROM AUTHOR]

A new species of the genus Leptus, L. (L.) brevitarsus sp. n., is described and illustrated from ectoparasitic larvae collected from grasshoppers (Orthoptera: Acrididae) in Australia. The new species belongs to the phalangii species group and torresianus species subgroup. An updated key to species of torresianus species subgroup is presented. [ABSTRACT FROM AUTHOR]

The testis specific X-linked genes whose evolution is traced here in the melanogaster species subgroup are thought to undergo fast rate of diversification. The CK2ßtes and NACbtes gene families encode the diverged regulatory b-subunits of protein kinase CK2 and the homologs of b-subunit of nascent peptide associated complex, respectively. We annotated the CK2btes-like genes related to CK2ßtes family in the D. simulans and D. sechellia genomes. The ancestor CK2btes-like genes preserved in D. simulans and D. sechellia are considered to be intermediates in the emergence of the D. melanogaster specific Stellate genes related to the CK2ßtes family. The CK2ßtes-like genes are more similar to the unique autosomal CK2ßtes gene than to Stellates, taking into account their peculiarities of polymorphism. The formation of a variant the CK2ßtes gene Stellate in D. melanogaster as a result of illegitimate recombination between a NACßtes promoter and a distinct polymorphic variant of CK2ßtes-like ancestor copy was traced. We found a close nonrandom proximity between the dispersed defective copies of DINE-1 transposons, the members of Helitron family, and the CK2btes and NACbtes genes, suggesting an involvement of DINE-1 elements in duplication and amplification of these genes. [ABSTRACT FROM AUTHOR]

Chromosome localization of sequences homologous to λ20p1.4 of the Drosophila melanogaster nuclear lamina DNA (nlDNA) was established by in situ hybridization in species of the melanogastersubgroup. DNA of the λ20p1.4 clone was shown to be located in the chromocenter in all the species examined. Laboratory strains of D. simulans, D. mauritiana, and D. sechellia exhibited interspecific differences in localization of λ20p1.4 nlDNA on chromosome arms. In eight natural populations, intraspecific polymorphism of λ20p1.4 nlDNA chromosome localization was shown to be present in D. simulans but absent in D. melanogaster. The possible participation of transposable elements in λ20p1.4 nlDNA relocation is discussed. [ABSTRACT FROM AUTHOR]

In contrast to male genitalia that typically exhibit patterns of rapid and divergent evolution among internally fertilizing animals, female genitalia have been less well studied and are generally thought to evolve slowly among closely-related species. As a result, few cases of male-female genital coevolution have been documented. In Drosophila, female copulatory structures have been claimed to be mostly invariant compared to male structures. Here, we re-examined male and female genitalia in the nine species of the D. melanogaster subgroup. We describe several new species-specific female genital structures that appear to coevolve with male genital structures, and provide evidence that the coevolving structures contact each other during copulation. Several female structures might be defensive shields against apparently harmful male structures, such as cercal teeth, phallic hooks and spines. Evidence for male-female morphological coevolution in Drosophila has previously been shown at the post-copulatory level (e.g., sperm length and sperm storage organ size), and our results provide support for male-female coevolution at the copulatory level. [ABSTRACT FROM AUTHOR]

The intragenomic distribution of five retrotransposon families ( 297, 1731, copia, mdg1 and roo) in the species of the melanogaster complex was studied by comparing results of the Southern blotting technique in males and females with those of in situ hybridization. The degree of structural polymorphism of each family in the different species was also investigated by restriction enzyme analysis. It was found that genomic distribution is a trait that depends on the family and species. The distribution of roo is mainly euchromatic in the four species and 1731 is heterochromatic, but the distribution of families 297, copia and mdg1 is markedly different in the melanogaster and simulans clades. These families were mainly euchromatic in D. melanogaster but heterochromatic in its sibling species. In the simulans clade most copia and mdg1 elements are located on chromosome Y. Differences in genomic distribution are unrelated with structural conservation. The relation of intragenomic distribution to phylogeny, transpositional activity and the role of the host genome are discussed. [ABSTRACT FROM AUTHOR]

The relationship between the net charge ofmolecules and their mobility on electrophoresis wasanalyzed for Drosophila alpha-amylases. Most ofthe differences in electrophoretic mobility, 98.2%, canbe explained by the charge state. Therefore fivereference amino acid sites, which are informativeresidues for charge differences among amylase isozymes,were considered for the evolution of the isozymes in Drosophila melanogaster. Theamylase isozymes in D. melanogaster can beclassified into three groups, I (AMY1,AMY2, and AMY3-A), II(AMY3-B and AMY4), and III(AMY5, AMY6-A, andAMY6-B), based on the differences in the reference sites. The mostprimitive amylase in D. melanogaster was foundto belong to Group I, most likely the AMY2isozyme. Groups II and III could have been derived fromGroup I. These results were confirmed by the analysis of 38amino acid sites with charge differences in Drosophila. [ABSTRACT FROM AUTHOR]

Drosophila ( Sophophora) subpulchrella Takamori and Watabe, sp. nov., of the D. suzukii subgroup in the D. melanogaster species group, is described from Japan and southern China, and compared with its sibling species, D. pulchrella Tan et al. distributed in the Yun-Gui Highland, south-western China. The results of cross-experiments show a complete pre-mating isolation between D. subpulchrella and D. pulchrella. [ABSTRACT FROM AUTHOR]

The Drosophila melanogasterspecies subgroup is a closely-knit collection of eight sibling species whose relationships are well defined. These species are too close for most evolutionary studies of euchromatic genes but are ideal to investigate the major changes that occur to DNA in heterochromatin over short periods during evolution. For example, it is not known whether the locations of genes in heterochromatin are conserved over this time. The 18S and 28S ribosomal RNA genes can be considered as genuine heterochromatic genes. In D. melanogasterthe rRNA genes are located at two sites, one each on the X and Y chromosome. In the other seven sibling species, rRNA genes are also located on the sex chromosomes but the positions often vary significantly, particularly on the Y. Furthermore, rDNA has been lost from the Y chromosome of both D. simulansand D. sechellia, presumably after separation of the line leading to present-day D. mauritiana.We conclude that changes to chromosomal position and copy number of rDNA arrays occur over much shorter evolutionary timespans than previously thought. In these respects the rDNA behaves more like the tandemly repeated satellite DNAs than euchromatic genes. [ABSTRACT FROM AUTHOR]

A new species of Leptus, L. baspinarisp. nov., is described and illustrated from larvae collected via pitfall traps (off-host) from Akçaova (Seferler) reservoir, Gökbel mountain, Aydin Province, Türkiye. The new species belongs to phalangii species group and killingtoni species subgroup. Leptus dubius Paoli and L. pouryayevalii Hakimitabar, Saboori & Fadaei are reported for the first time from Türkiye, and L. dubius Paoli is redescribed and illustrated based on Turkish specimens. New metric data are given for L. pouryayevalii. Keys to killingtoni, torresianus, dubius, and hospeticus species subgroups are presented, and definitions of dubius, bogoriacus and pasopaicus species subgroups are corrected. [ABSTRACT FROM AUTHOR]

In this study, the region corresponding to the Thr–Gly region of the period ( per) gene in the Drosophila nasuta subgroup of species was sequenced. The results showed that this region was highly conserved in the D. nasuta subgroup. There were only nine variable sites found in this 300-bp-long region, all located in two small regions highly variable among Drosophila species. No length variation was observed either within this subgroup or in the Yunnan (YN) population of D. albomicans. The deduced amino acid sequences were identical for all 14 taxa in the D. nasuta subgroup, and a stretch of alternating Thr–Gly pairs was not observed in this subgroup. A phylogenetic tree was constructed. The clustering of some species was in general agreement with previous works, but it also raised some question on the phylogenetic relationship between the nasuta species. The data did not implicate the Thr–Gly region playing a role in behavioral isolation in this subgroup of Drosophila. [ABSTRACT FROM AUTHOR]

A striking diversity of compound eye size and shape has evolved among insects. The number of ommatidia and their size are major determinants of the visual sensitivity and acuity of the compound eye. Each ommatidium is composed of eight photoreceptor cells that facilitate the discrimination of different colours via the expression of various light sensitive Rhodopsin proteins. It follows that variation in eye size, shape, and opsin composition is likely to directly influence vision. We analyzed variation in these three traits in D. melanogaster, D. simulans and D. mauritiana. We show that D. mauritiana generally has larger eyes than its sibling species, which is due to a combination of larger ommatidia and more ommatidia. In addition, intra- and inter-specific differences in eye size among D. simulans and D. melanogaster strains are mainly caused by variation in ommatidia number. By applying a geometric morphometrics approach to assess whether the formation of larger eyes influences other parts of the head capsule, we found that an increase in eye size is associated with a reduction in the adjacent face cuticle. Our shape analysis also demonstrates that D. mauritiana eyes are specifically enlarged in the dorsal region. Intriguingly, this dorsal enlargement is associated with enhanced expression of rhodopsin 3 in D. mauritiana. In summary, our data suggests that the morphology and functional properties of the compound eyes vary considerably within and among these closely related Drosophila species and may be part of coordinated morphological changes affecting the head capsule. [ABSTRACT FROM AUTHOR]

Zaprionus is an important drosophilid genus in the Afrotropical region. Here, two new species, Z. burlai n. sp. and Z. tsacasi n. sp., are described from Tanzania and São Tomé, respectively. The two species show incomplete reproductive isolation with Z. tuberculatus Malloch and Z. sepsoides Duda, respectively, with intercrosses producing fertile females but sterile males. The latter two have long been considered sibling species and together with three other species (Z. mascariensis Tsacas & David, Z. kolodkinae Chassagnard & Tsacas, and Z. verruca Chassagnard & McEvey) form the tuberculatus subgroup. The phylogenetic relationships of these seven species of the subgroup were revised in light of mitochondrial (COII) gene sequences and wing morphometrics. Mitochondrial DNA firmly distinguished most of the species, except for a triad of Z. tuberculatus, Z. verruca, and Z. burlai. Wing morphometrics was able to distinguish between closely related species and also indicated the altitudinal origin of each species. Most species can be identified through internal anatomy of the reproductive system (testis and seminal receptacle lengths), and the discovery of the new species with incomplete reproductive isolation may help in understanding the genetic basis of this variation through interspecific hybridization. The molecular phylogeny reconfirmed the Malagasy origin of the subgroup during the Late Pliocene. Colonization of Africa probably involved two independent events during the Pleistocene. [ABSTRACT FROM AUTHOR]

We report the results of a phylogenetic survey of the retrotransposon copia in the melanogaster subgroup of the Drosophila genus. The polymerase chain reaction was used to amplify the copia 5' long terminal repeat and the adjacent untranslated leader region from representative melanogaster subgroup species. Restriction and sequence analyses of this region reveal discrete classes of copia size variants within the melanogaster subgroup. Phylogenetic comparisons of copia sequence data indicate that the size variants represent different copia subfamilies which diverged prior to their distribution in the melanogaster subgroup. Our results also suggest that copia elements have been subject to horizontal and vertical transmission during their evolution. [ABSTRACT FROM PUBLISHER]

Fractionation of total adult DNA of five of the seven species of the melanogaster species sub-group of Drosophila in actinomycin D and distamycin A caesium density gradients has revealed the presence of three main-band DNA components, common to all species, and ten satellite DNAs that are distributed between the species. Satellite DNAs are either unique to a species or common to two or more species. The abundance of a common satellite DNA varies between species. There is no simple relationship between the presence of a satellite DNA and a branch point of phylogenetic divergence; nevertheless the arrangement of the species in a phylogeny that is based on the numbers of satellites held in common accurately reflects the pattern of relationships between the same species based on differences in inversions of polytene chromosomes. The species can be similarly arranged according to the compositions of their mitochondrial DNAs. It is possible that the same basic set of sequences, each of low frequency, is common to all species with arbitrary or selected amplification of particular sequences to differing extents in individual species. The conservation of satellites in the group and the close parallel between the distributions of satellites and inversions between the species suggests that either the processes that operate to change both chromosomal phenomena are similarly time-dependent and occurring at relatively low rates or that their rates of change are restricted according to some undetermined functions of these aspects of the genome. [ABSTRACT FROM AUTHOR]

The Threonine-Glycine (Thr-Gly) region of the period gene ( per) in Drosophila was compared in the eight species of the D. melanogaster subgroup. This region can be divided into a diverged variable-length segment which is flanked by more conserved sequences. The number of amino acids encoded in the variable-length region ranges from 40 in D. teissieri to 69 in D. mauritiana. This is similar to the range found within natural populations of D. melanogaster. It was possible to derive a Thr-Gly 'allele' of one species from that of another by invoking hypothetical Thr-Gly intermediates. A phylogeny based on the more conserved flanking sequences was produced. The results highlighted some of the problems which are encountered when highly polymorphic genes are used to infer phylogenies of closely related species. [ABSTRACT FROM AUTHOR]

Mitochondrial DNA (mtDNA) restriction site maps for nine species of the Drosophila obscura subgroup and for Drosophila melanogaster were established. Taking into account all restriction enzymes (12) and strains (45) analyzed, a total of 105 different sites were detected, which corresponds to a sample of 3.49% of the mtDNA genome. Based on nucleotide divergences, two phylogenetic trees were constructed assuming either constant or variable rates of evolution. Both methods led to the same relationships. Five differentiated clusters were found for the obscura subgroup species, one Nearctic, represented by Drosophila pseudoobscura, and four Palearctic, two grouping the related triads of species Drosophila subobscura, Drosophila madeirensis, Drosophila guanche, and Drosophila ambigua, Drosophila obscura, Drosophila subsilvestris, and two more represented by one species each, Drosophila bifasciata, and Drosophila tristis. The different Palearctic clusters are as distant between themselves as with the Nearctic one. For the related species D. subobscura, D. madeirensis, and D. guanche, the pair D. subobscura-D. madeirensis is the closest one. The relationships found by nucleotide divergence were confirmed by differences in mitochondrial genome size, with related species sharing similar genome lengths and differing from the distant ones. The total mtDNA size range for the obscura subgroup species was from 15.5 kb for D. pseudoobscura to 17.1 for D. tristis. [ABSTRACT FROM AUTHOR]

Three new species of predatory mites belonging to the genus Amblyseius Berlese (Acari: Phytoseiidae), A. latisetosussp. nov., A. unodentatussp. nov., and A. altaiensissp. nov. are described based on the material collected from Altai Republic, Russia. The new species are assigned to the obtusus species group and andersoni species subgroup by having setae J2 and Z1, short and minute setae z4, sub-pentagonal ventrianal shield, and bell-shaped calyx of spermatheca. All new species were compared with each other and all other Amblyseius species known to date. The main diagnostic characters of these species are measurements of prominent dorsal setae, ventral setae JV5 and macrosetae on leg IV, cheliceral dentition, number of setae on genu II as well as small rounded and distinct pre-anal pores on ventrianal shield. [ABSTRACT FROM AUTHOR]

Background: Paenibacillus polymyxa is a bacterial species of high interest, as suggested by the increased number of publications on its functions in the past years. Accordingly, the number of described strains and sequenced genomes is also on the rise. While functional diversity of P. polymyxa has been suggested before, the available genomic data is now sufficient for robust comparative genomics analyses. Results: Using 157 genomes, we found significant disparities among strains currently affiliated to P. polymyxa. Multiple taxonomic groups were identified with conserved predicted functions putatively impacting their respective ecology. As strains of this species have been reported to exhibit considerable potential in agriculture, medicine, and bioremediation, it is preferable to clarify their taxonomic organization to facilitate reliable and durable approval as active ingredients. Conclusions: Strains currently affiliated to P. polymyxa can be separated into two major species groups with differential potential in nitrogen fixation, plant interaction, secondary metabolism, and antimicrobial resistance, as inferred from genomic data. [ABSTRACT FROM AUTHOR]

Leptus (Leptus) pouryayevalii sp. nov. (Acari: Erythraeidae), collected by shaking the leaves of weeds on white tray (off host) from Koushk Bala village, Chalous road, Alborz Province, Iran, is described and illustrated based on larva. This species belongs to the sudanensis species group and hospeticus species subgroup which can be identified based on the following characters: TFe I without solenidion, Ge I with two solenidia. [ABSTRACT FROM AUTHOR]

The satyr of Greek mythology was half‐man, half‐goat, with an animal persona signifying immoderate sexual appetites. In biology, satyrization is the disruption of reproduction in matings between closely related species. Interestingly, its effects are often reciprocally asymmetric, manifesting more strongly in one direction of heterospecific mating than the other. Heterospecific matings are well known to result in female fitness costs due to the production of sterile or inviable hybrid offspring and can also occur due to reduced female sexual receptivity, lowering the likelihood of any subsequent conspecific matings. Here we investigated the costs and mechanisms of satyrization in the Drosophila melanogaster species subgroup of fruitflies. The results showed that D. simulans females experienced higher fitness costs from a loss of remating opportunities due to significantly reduced post‐mating sexual receptivity than did D. melanogaster females, as a result of reciprocal heterospecific matings. Reciprocal tests of the effects of male reproductive accessory gland protein (Acp) injections on female receptivity in pairwise comparisons between D. melanogaster and five other species within the melanogaster species subgroup revealed significant post‐mating receptivity asymmetries. This was due to variation in the effects of heterospecific Acps within species with which D. melanogaster can mate, and significant but nonasymmetric Acp effects in species with which it cannot. We conclude that asymmetric satyrization due to post‐mating effects of Acps may be common among diverging and hybridising species. The findings are of interest in understanding the evolution of reproductive isolation and species divergence. [ABSTRACT FROM AUTHOR]

Four new species, Abrolophus quadrapexicis Xu & Jin sp. nov., Grandjeanella dianensis Xu & Jin sp. nov., Leptus (Leptus) trisolenidionus Xu & Jin sp. nov. and Hirstiosoma tibetensis Xu & Jin sp. nov. are described and illustrated based on larvae. The species Hirstiosoma sadafae (Amin, Khanjani & Nadri) comb. nov. is transferred from the genus Sphaerotarsus to Hirstiosoma based on gnathosoma with two pairs barbed hypostomalae (as and bs), as and bs almost equal in length. H. tibetensissp. nov. and G. dianensissp. nov. are from the Tibetan Plateau (Qinghai-Tibet Plateau), a unique geographical unit of the highest altitude in the world. The described H. tibetensissp. nov. from the Tibetan Plateau represents a newly recorded subfamily from China, namely Hirstiosomatinae (Smarididae) with the genus Hirstiosoma. The genus Grandjeanella including six species distributed in Australia, New Zealand and Indonesia (Sulawesi), is new to China and the Eurasian continent as G. dianensissp. nov. found in the southern Tibetan Plateau (Gaoligongshan National Natural Reserve). In China Abrolophus has been known from the Oriental realm, A. quadrapexicissp. nov. makes it cover both the Palaearctic and Oriental realm of China. L. (L.) trisolenidionussp. nov. belongs to the phalangii species group and torresianus species subgroup, which contains three species previously known in Oceania (Australia) and South America (French Guiana) and here is the first report in Asia (China). [ABSTRACT FROM AUTHOR]

In the present paper on the Western European Trichoptera we revise or overview the Platyphylax and Simaphylax limnephiline genera, as well as establish and/or overview the Drusus chapmani, Chaetopteryx gessneri and C. gonospina species complexes based on the principles and procedures of our fine phenomics. Having collected a new Drusus chrysotus (Rambur, 1842) specimen we have reconfirmed its delineation from its eastern sibling species Drusus lapos Oláh, 2017. By the paraproct, the Drusus spelaeus siblings in the Drusus mixtus species group are related to the Drusus siveci species complex in the Drusus discolor species group. Our discovery of a population of Drusus spelaeus with paramere structure similar to that of the Drusus discolor species group indicates further the importance of chimeric processes in species integrative organisation. Due to contradictory drawings published we have re-examined and redescribed the female of Drusus spelaeus. After surveying the recent taxonomic history of the Allogamus auricollis species subgroup we have raised the subspecies status to species rank of Allogamus auricollis bauerii (Kolenati, 1859); A. brauerii stat. nov. Chaetopteryx gessneri tomaszewski Moretti, 1991 was elevated to species rank: Ch. tomaszewski stat. nov. and Chaetopteryx kimera Oláh & Vinçon, 2021, a rather unique chimeric species having several character states of different origin was transferred to Consorophylax genus: C. kimera (Oláh & Vinçon, 2021) comb. nov. Furthermore, 17 new species were described: Wormaldia ariega, W. ligurica, W. maritima, Drusus alethes, D. italiano, Chaetopteryx tompula, C. cantabrica, C. decampsi, C. pyrenaica, Consorophylax cairos, C. lagoverde, C. livek, C. seolan, Platyphylax vinconi, Simaphylax coppai, S. andorricus and S. ariegeus spp. nov. Among them, ten were collected in France, five in Italy, one in Slovenia and one in Spain. Moreover, we report for the first time Potamophylax spinulifer Moretti, 1994 and Beraeamyia gudrunae Malicky, 2002 from France and Simaphylax altuspyrenaicus from Spain. [ABSTRACT FROM AUTHOR]

The number and location of crossovers across genomes are highly regulated during meiosis, yet the key components controlling them are fast evolving, hindering our understanding of the mechanistic causes and evolutionary consequences of changes in crossover rates. Drosophila melanogaster has been a model species to study meiosis for more than a century, with an available high-resolution crossover map that is, nonetheless, missing for closely related species, thus preventing evolutionary context. Here, we applied a novel and highly efficient approach to generate whole-genome high-resolution crossover maps in D. yakuba to tackle multiple questions that benefit from being addressed collectively within an appropriate phylogenetic framework, in our case the D. melanogaster species subgroup. The genotyping of more than 1,600 individual meiotic events allowed us to identify several key distinct properties relative to D. melanogaster. We show that D. yakuba, in addition to higher crossover rates than D. melanogaster, has a stronger centromere effect and crossover assurance than any Drosophila species analyzed to date. We also report the presence of an active crossover-associated meiotic drive mechanism for the X chromosome that results in the preferential inclusion in oocytes of chromatids with crossovers. Our evolutionary and genomic analyses suggest that the genome-wide landscape of crossover rates in D. yakuba has been fairly stable and captures a significant signal of the ancestral crossover landscape for the whole D. melanogaster subgroup, even informative for the D. melanogaster lineage. Contemporary crossover rates in D. melanogaster, on the other hand, do not recapitulate ancestral crossovers landscapes. As a result, the temporal stability of crossover landscapes observed in D. yakuba makes this species an ideal system for applying population genetic models of selection and linkage, given that these models assume temporal constancy in linkage effects. Our studies emphasize the importance of generating multiple high-resolution crossover rate maps within a coherent phylogenetic context to broaden our understanding of crossover control during meiosis and to improve studies on the evolutionary consequences of variable crossover rates across genomes and time. Author summary: Meiotic recombination is a fundamental cellular process required for the formation of gametes in most eukaryotic organisms. Recombination also plays a fundamental role in evolution, increasing rates of adaptation. Paradoxically for such an essential process, key components evolve fast, and model organisms differ vastly in number of recombination events and distribution across chromosomes. This variation has limited our understanding of how recombination is controlled or why it can vary according to environmental cues. D. melanogaster has been a model species to study meiosis and recombination for more than a century and, in this study, we applied a new and highly efficient whole-genome genotyping scheme to identify recombination properties for a closely related species, D. yakuba, thus providing an informative counterpoint and needed phylogenetic context. Our results describe important differences relative to D. melanogaster, including the first description of a mechanism favoring the segregation of recombinant chromatids to the functional egg pole under benign conditions. We argue that such a mechanism may also be active in other species. Moreover, our studies suggest that D. yakuba has maintained its recombination landscape for a longer time than D. melanogaster, indicating that the former species may be more adequate for evolutionary analyses. Combined, we show the importance of tackling the current siloed approach that focuses on model species with a more comprehensive analysis that requires the inclusion of closely related species when studying the causes and consequences of recombination variation. [ABSTRACT FROM AUTHOR]

A comprehensive taxonomic assessment of the most agriculturally important and highly diverse spider mite genus, Oligonychus Berlese (Acari: Tetranychidae) was performed. The sub-generic division, species groups, doubtful species, species complexes and the interpretation of a key generic character are discussed. Based on the orientation of the male aedeagus, only two subgenera, namely Oligonychus Berlese (aedeagus downturned) and Reckiella Tuttle & Baker (aedeagus upturned), are valid in the genus Oligonychus. The subgenera Homonychus Wainstein, Metatetranychoides Wainstein, and Wainsteiniella Tuttle & Baker are considered to be synonyms of the subgenus Oligonychus, whereas the subgenus Pritchardinychus Wainstein is proposed as a synonym of the subgenus Reckiella. Moreover, based on female morphological characters, four species groups (coffeae, exsiccator, iseilemae, and peruvianus) and 11 species subgroups (aceris, biharensis, coffeae, comptus, exsiccator, gossypii, iseilemae, peruvianus, pritchardi, smithi, and subnudus) are suggested in the subgenera Oligonychus and Reckiella. Fourteen Oligonychus species are proposed as species inquirendae, and potential cryptic species complexes in the genus Oligonychus are briefly highlighted. It is agreed that the clunal seta h1 is always absent, while the para-anal setae h2 and h3 are always present in the genus Oligonychus. A key to subgenera, species groups, and species subgroups of the genus Oligonychus is provided. [ABSTRACT FROM AUTHOR]

This paper describes a new species of athecate earthworm belonging to the illotus species-group of the genus Amynthas Kinberg from Taiwan. It is Amynthas hohuanmontis sp. nov. from Mt Hohuan at an elevation of 3000 m in the Central Mountain Range. The athecate earthworm Amynthas pusillus (Ohfuchi) from Ishigaki Island, Riukiu is found to be synonymous with Amynthas assacceus (Chen) from Hainan Island, China. Accordingly, the A. illotus species-group currently consists of A. hohuanmontis sp. nov. from Taiwan, A. illotus (Gates) from Yunnan and Riukiu, A. assacceus (Chen) of Hainan and Riukiu, A. sheni (Chen) from Hong Kong and A. oyuensis (Ohfuchi) from Japan. Based on characters of particularly the porophore structure, the five species are divided into two species-subgroups: the sheni species-subgroup of A. sheni and A. hohuanmontis , and the assacceus species-subgroup of A. illotus, A. assacceus and A. oyuensis. The two subgroups might have differentiated from two independent ancestors. The five species show an arc-shaped distribution in the peripheral regions of the East Asian continent (Yunnan, Hainan, Hong Kong, Taiwan, Riukiu and Japan), suggesting them to be survivors from the Pleistocene ice ages. [ABSTRACT FROM AUTHOR]

The Saturniidae is one of the most emblematic families of moths, comprising nearly 3000 species distributed globally. In this study, DNA barcode analysis and comparative morphology were combined to describe three new species within the genus Automeris, which is the most diverse genus in the family. Automeris llaneros Decaëns, Rougerie & Bonilla, sp. nov., Automeris mineros Decaëns, Rougerie & Bonilla, sp. nov., and Automeris belemensis Decaëns, Rougerie & Bénéluz, sp. nov. are described from the Colombian Orinoco watershed, the Colombian Eastern Cordillera, and the area of endemism of Belém in the Brazilian Amazonia, respectively. They all belong to the Automeris bilinea (Walker, 1855) species subgroup, which comprises a number of species that are sometimes difficult to distinguish from each other using morphology alone. Here, the description of these three new species is based on significant differences from their closest relatives, either in terms of wing patterns, genitalia, DNA barcodes or a combination of these features. [ABSTRACT FROM AUTHOR]

Background: Brucellosis caused by Brucella (B. abortus) and Brucella melitensis (B. melitensis) poses a significant threat to human and animal populations. The World Health Organization (WHO) recommends rifampin and cotrimoxazole as first-line treatments for pediatric brucellosis. However, emerging resistance to these antibiotics raises concerns regarding their continued efficacy. This systematic review and meta-analysis aimed to quantitatively assess the prevalence of rifampin and cotrimoxazole resistance in B. abortus and B. melitensis. Methods: Eligible studies were identified by systematically searching various databases, such as Scopus, PubMed, Web of Science, and EMBASE databases, using specified search terms until 18 June 2024. The inclusion criteria required studies in English to report the resistance proportion with sample size details. The meta-analysis utilized a random-effects model to assess heterogeneity using the Q-test and I2 statistic. Meta-regression and subgroup analyses explored temporal, geographical, and guideline-related variations in resistance prevalence. Results: Among the 905 records, 59 studies spanning 21 countries (1976 to 2024) met the inclusion criteria. The prevalence of cotrimoxazole resistance, based on 3,756 isolates, was 0.034 (95% CI, 0.017, 0.068), with increasing trends over time, especially in B. melitensis. Rifampin resistance, involving 3,938 isolates, had a prevalence of 0.046 (95% CI, 0.027, 0.077), showing temporal and species-specific increases. Subgroup analyses revealed significant variations in resistance based on temporal, geographical, and guideline-related factors. Conclusions: This systematic review and meta-analysis highlighted an alarming rise in cotrimoxazole and rifampin resistance in B. abortus and B. melitensis, particularly in pediatric brucellosis. Temporal, geographical, and species-specific variations underscore the dynamic nature of antibiotic resistance, emphasizing the need for targeted interventions, surveillance, and global collaboration to preserve the efficacy of essential antibiotics in brucellosis treatment. The limitations include potential biases and the retrospective nature of the included studies, emphasizing the urgent need for standardized surveillance methodologies and robust reporting mechanisms. [ABSTRACT FROM AUTHOR]

Centromeres reside in rapidly evolving, repeat-rich genomic regions, despite their essential function in chromosome segregation. Across organisms, centromeres are rich in selfish genetic elements such as transposable elements and satellite DNAs that can bias their transmission through meiosis. However, these elements still need to cooperate at some level and contribute to, or avoid interfering with, centromere function. To gain insight into the balance between conflict and cooperation at centromeric DNA, we take advantage of the close evolutionary relationships within the Drosophila simulans clade—D. simulans, D. sechellia, and D. mauritiana—and their relative, D. melanogaster. Using chromatin profiling combined with high-resolution fluorescence in situ hybridization on stretched chromatin fibers, we characterize all centromeres across these species. We discovered dramatic centromere reorganization involving recurrent shifts between retroelements and satellite DNAs over short evolutionary timescales. We also reveal the recent origin (<240 Kya) of telocentric chromosomes in D. sechellia, where the X and fourth centromeres now sit on telomere-specific retroelements. Finally, the Y chromosome centromeres, which are the only chromosomes that do not experience female meiosis, do not show dynamic cycling between satDNA and TEs. The patterns of rapid centromere turnover in these species are consistent with genetic conflicts in the female germline and have implications for centromeric DNA function and karyotype evolution. Regardless of the evolutionary forces driving this turnover, the rapid reorganization of centromeric sequences over short evolutionary timescales highlights their potential as hotspots for evolutionary innovation. Centromeres reside in rapidly evolving, repeat-rich genomic regions, despite their essential function in chromosome segregation. This study of centromere evolution over short evolutionary timescales in Drosophila reveals dramatic centromere reorganization involving recurrent shifts between retroelements and satellite DNAs. [ABSTRACT FROM AUTHOR]