Phylogenetic and Comparative Genomics Study of Papilionidae Based on Mitochondrial Genomes.

Most species of Papilionidae are large and beautiful ornamental butterflies. They are recognized as model organisms in ecology, evolutionary biology, genetics, and conservation biology but present numerous unresolved phylogenetic problems. Complete mitochondrial genomes (mitogenomes) have been widely used in phylogenetic studies of butterflies, but mitogenome knowledge within the family Papilionidae is limited, and its phylogeny is far from resolved. In this study, we first report the mitogenome of Byasa confusa from the subfamily Papilioninae of Papilionidae. The mitogenome of B. confusa is 15,135 bp in length and contains 13 protein-coding genes, 22 transfer RNA genes, 2 ribosomal RNA genes, and an AT-rich control region (CR), closely mirroring the genomic structure observed in related butterfly species. Comparative analysis of 77 Papilionidae mitogenomes shows gene composition and order to be identical to that of an ancestral insect, and the AT bias, Ka/Ks, and relative synonymous codon usage (RSCU) are all consistent with that of other reported butterfly mitogenomes. We conducted phylogenetic analyses using maximum-likelihood (ML) and Bayesian-inference (BI) methods, with 77 Papilionidae species as ingroups and two species of Nymphalidae and Lycaenidae as outgroups. The phylogenetic analysis indicated that B. confusa were clustered within Byasa. The phylogenetic trees show the monophyly of the subfamily Papilioninae and the tribes Leptocircini, Papilionini, and Troidini. The data supported the following relationships in tribe level on Papilioninae: (((Troidini + Papilionini) + Teinopalpini) + Leptocircini). The divergence time analysis suggests that Papilionidae originated in the late Creataceous. Overall, utilizing the largest number of Papilionidae mitogenomes sequenced to date, with the current first exploration in a phylogenetic analysis on Papilionidae (including four subfamilies), this study comprehensively reveals the mitogenome characteristics and mitogenome-based phylogeny, providing information for further studies on the mitogenome, phylogeny, evolution, and taxonomic revision of the Papilionidae family.

Museomics help resolving the phylogeny of snowfinches (Aves, Passeridae, Montifringilla and allies).

Historical specimens from museum collections provide a valuable source of material also from remote areas or regions of conflict that are not easily accessible to scientists today. With this study, we are providing a taxon-complete phylogeny of snowfinches using historical DNA from whole skins of an endemic species from Afghanistan, the Afghan snowfinch, Pyrgilauda theresae. To resolve the strong conflict between previous phylogenetic hypotheses, we generated novel mitogenome sequences for selected taxa and genome-wide SNP data using ddRAD sequencing for all extant snowfinch species endemic to the Qinghai-Tibet Plateau (QTP) and for an extended intraspecific sampling of the sole Central and Western Palearctic snowfinch species (Montifringilla nivalis). Our phylogenetic reconstructions unanimously refuted the previously suggested paraphyly of genus Pyrgilauda. Misplacement of one species-level taxon (Onychostruthus tazcanowskii) in previous snowfinch phylogenies was undoubtedly inferred from chimeric mitogenomes that included heterospecific sequence information. Furthermore, comparison of novel and previously generated sequence data showed that the presumed sister-group relationship between M. nivalis and the QTP endemic M. henrici was suggested based on flawed taxonomy. Our phylogenetic reconstructions based on genome-wide SNP data and on mitogenomes were largely congruent and supported reciprocal monophyly of genera Montifringilla and Pyrgilauda with monotypic Onychostruthus being sister to the latter. The Afghan endemic P. theresae likely originated from a rather ancient Pliocene out-of-Tibet dispersal probably from a common ancestor with P. ruficollis. Our extended trans-Palearctic sampling for the white-winged snowfinch, M. nivalis, confirmed strong lineage divergence between an Asian and a European clade dated to 1.5 - 2.7 million years ago (mya). Genome-wide SNP data suggested subtle divergence among European samples from the Alps and from the Cantabrian mountains.

Mitogenomic phylogeny, biogeography, and cryptic divergence of the genus Silurus (Siluriformes: Siluridae).

The genus Silurus, an important group of catfish, exhibits heterogeneous distribution in Eurasian freshwater systems. This group includes economically important and endangered species, thereby attracting considerable scientific interest. Despite this interest, the lack of a comprehensive phylogenetic framework impedes our understanding of the mechanisms underlying the extensive diversity found within this genus. Herein, we analyzed 89 newly sequenced and 20 previously published mitochondrial genomes (mitogenomes) from 13 morphological species to reconstruct the phylogenetic relationships, biogeographic history, and species diversity of Silurus. Our phylogenetic reconstructions identified eight clades, supported by both maximum-likelihood and Bayesian inference. Sequence-based species delimitation analyses yielded multiple molecular operational taxonomic units (MOTUs) in several taxa, including the Silurus asotus complex (four MOTUs) and Silurus microdorsalis (two MOTUs), suggesting that species diversity is underestimated in the genus. A reconstructed time-calibrated tree of Silurus species provided an age estimate of the most recent common ancestor of approximately 37.61 million years ago (Ma), with divergences among clades within the genus occurring between 11.56 Ma and 29.44 Ma, and divergences among MOTUs within species occurring between 3.71 Ma and 11.56 Ma. Biogeographic reconstructions suggested that the ancestral area for the genus likely encompassed China and the Korean Peninsula, with multiple inferred dispersal events to Europe and Central and Western Asia between 21.78 Ma and 26.67 Ma and to Japan between 2.51 Ma and 18.42 Ma. Key factors such as the Eocene-Oligocene extinction event, onset and intensification of the monsoon system, and glacial cycles associated with sea-level fluctuations have likely played significant roles in shaping the evolutionary history of the genus Silurus.

Complete Mitogenome sequencing of the fish louse Argulus japonicus (Crustacea: Branchiura): Comparative analyses and phylogenetic implications.

The fish louse Argulus japonicus, a branchiuran crustacean of the Argulidae family, is attracting increasing attention because of its parasitic tendencies and significant health threats to global fish farming. The mitogenomes can yield a foundation for studying epidemiology, genetic diversity, and molecular ecology and therefore may be used to assist in the surveillance and control of A. japonicus. In this study, we sequenced and assembled the complete mitogenome of A. japonicus to shed light on its genetic and evolutionary blueprint. Our investigation indicated that the 15,045-bp circular genome of A. japonicus encodes 13 protein-coding genes (PCGs), 22 transfer RNAs (tRNAs), and 2 ribosomal RNAs (rRNAs) with significant AT and GC skews. Comparative genomics provided an evolutionary scenario for the genetic diversity of 13 PCGs: all were under purifying selection, with cox1 and nad6 having the lowest and highest evolutionary rates, respectively. Genome-wide phylogenetic trees established a close relationship between species of the families Argulidae (Arguloida) and Armilliferidae (Porocephalida) within Crustacea, and further, A. japonicus and Argulus americanus were determined to be more closely related to each other than to others within the family Argulidae. Single PCG-based phylogenies supported nad1 and nad6 as the best genetic markers for evolutionary and phylogenetic studies for branchiuran crustaceans due to their similar phylogenetic topologies with those of genome-based phylogenetic analyses. To sum up, these comprehensive mitogenomic data of A. japonicus and related species refine valuable marker resources and should contribute to molecular diagnostic methods, epidemiological investigations, and ecological studies of the fish ectoparasites in Crustacea.

Boring systematics: A genome skimmed phylogeny of ctenostome bryozoans and their endolithic family Penetrantiidae with the description of one new species.

Ctenostomes are a group of gymnolaemate bryozoans with an uncalcified chitinous body wall having few external, skeletal characters. Hence, species identification is challenging and their systematics remain poorly understood, even more so when they exhibit an endolithic (boring) lifestyle. Currently, there are four Recent families of endolithic bryozoans that live inside mineralized substrates like mollusk shells. In particular, Penetrantiidae Silén, 1946 has received considerable attention and its systematic affinity to either cheilostomes or ctenostomes has been debated. Species delimitation of penetrantiids remains difficult, owing to a high degree of colonial and zooidal plasticity. Consequently, an additional molecular approach is essential to unravel the systematics of penetrantiids, their phylogenetic placement and their species diversity. We therefore sequenced the mitochondrial (mt) genomes and two nuclear markers of 27 ctenostome species including nine penetrantiids. Our phylogeny supports the Penetrantiidae as a monophyletic group placed as sister taxon to the remaining ctenostomes alongside paludicellids, arachnidioids and terebriporids. The boring family Terebriporidae d'Orbigny, 1847 were previously considered to be among vesicularioids, but our results suggest an arachnidioid affinity instead. Ctenostome paraphyly is supported by our data, as the cheilostomes nest within them. A Multiporata clade is also well supported, including the former victorelloid genus Sundanella. Altogether, this study provides new insights into ctenostome systematics, assists with species delimitation and contributes to our understanding of the bryozoan tree of life.

Comparative Analysis of the Complete Mitochondrial Genomes of Three Sisoridae (Osteichthyes, Siluriformes) and the Phylogenetic Relationships of Sisoridae.

The family Sisoridae is one of the largest and most diverse Asiatic catfish families, with most species occurring in the water systems of the Qinhai-Tibetan Plateau and East Himalayas. At present, the phylogenetic relationship of the Sisoridae is relatively chaotic. In this study, the mitochondrial genomes (mitogenomes) of three species Creteuchiloglanis kamengensis, Glaridoglanis andersonii, and Exostoma sp. were systematically investigated, the phylogenetic relationships of the family were reconstructed and to determine the phylogenetic position of Exostoma sp. within Sisoridae. The lengths of the mitogenomes' sequences of C. kamengensis, G. andersonii, and Exostoma sp. were 16,589 bp, 16,531 bp, and 16,529 bp, respectively. They all contained one identical control region (D-loop), two ribosomal RNAs (rRNAs), 13 protein-coding genes (PCGs) and 22 transfer RNA (tRNA) genes. We applied two approaches, Bayesian Inference (BI) and Maximum Likelihood (ML), to construct phylogenetic trees. Our findings revealed that the topological structure of both ML and BI trees exhibited significant congruence. Specifically, the phylogenetic tree strongly supports the monophyly of Sisorinae and Glyptosternoids and provides new molecular biological data to support the reconstruction of phylogenetic relationships with Sisoridae. This study is of great scientific value for phylogenetic and genetic variation studies of the Sisoridae.

Comparative mitogenomic analysis of subterranean and surface amphipods (Crustacea, Amphipoda) with special reference to the family Crangonyctidae.

Mitochondrial genomes play important roles in studying genome evolution, phylogenetic analyses, and species identification. Amphipods (Class Malacostraca, Order Amphipoda) are one of the most ecologically diverse crustacean groups occurring in a diverse array of aquatic and terrestrial environments globally, from freshwater streams and lakes to groundwater aquifers and the deep sea, but we have a limited understanding of how habitat influences the molecular evolution of mitochondrial energy metabolism. Subterranean amphipods likely experience different evolutionary pressures on energy management compared to surface-dwelling taxa that generally encounter higher levels of predation and energy resources and live in more variable environments. In this study, we compared the mitogenomes, including the 13 protein-coding genes involved in the oxidative phosphorylation (OXPHOS) pathway, of surface and subterranean amphipods to uncover potentially different molecular signals of energy metabolism between surface and subterranean environments in this diverse crustacean group. We compared base composition, codon usage, gene order rearrangement, conducted comparative mitogenomic and phylogenomic analyses, and examined evolutionary signals of 35 amphipod mitogenomes representing 13 families, with an emphasis on Crangonyctidae. Mitogenome size, AT content, GC-skew, gene order, uncommon start codons, location of putative control region (CR), length of rrnL and intergenic spacers differed between surface and subterranean amphipods. Among crangonyctid amphipods, the spring-dwelling Crangonyx forbesi exhibited a unique gene order, a long nad5 locus, longer rrnL and rrnS loci, and unconventional start codons. Evidence of directional selection was detected in several protein-encoding genes of the OXPHOS pathway in the mitogenomes of surface amphipods, while a signal of purifying selection was more prominent in subterranean species, which is consistent with the hypothesis that the mitogenome of surface-adapted species has evolved in response to a more energy demanding environment compared to subterranean amphipods. Overall, gene order, locations of non-coding regions, and base-substitution rates points to habitat as an important factor influencing the evolution of amphipod mitogenomes.

The effect of missing data on evolutionary analysis of sequence capture bycatch, with application to an agricultural pest.

Sequence capture is a genomic technique that selectively enriches target sequences before high throughput next-generation sequencing, to generate specific sequences of interest. Off-target or 'bycatch' data are often discarded from capture experiments, but can be leveraged to address evolutionary questions under some circumstances. Here, we investigated the effects of missing data on a variety of evolutionary analyses using bycatch from an exon capture experiment on the global pest moth, Helicoverpa armigera. We added > 200 new samples from across Australia in the form of mitogenomes obtained as bycatch from targeted sequence capture, and combined these into an additional larger dataset to total > 1000 mitochondrial cytochrome c oxidase subunit I (COI) sequences across the species' global distribution. Using discriminant analysis of principal components and Bayesian coalescent analyses, we showed that mitogenomes assembled from bycatch with up to 75% missing data were able to return evolutionary inferences consistent with higher coverage datasets and the broader literature surrounding H. armigera. For example, low-coverage sequences broadly supported the delineation of two H. armigera subspecies and also provided new insights into the potential for geographic turnover among these subspecies. However, we also identified key effects of dataset coverage and composition on our results. Thus, low-coverage bycatch data can offer valuable information for population genetic and phylodynamic analyses, but caution is required to ensure the reduced information does not introduce confounding factors, such as sampling biases, that drive inference. We encourage more researchers to consider maximizing the potential of the targeted sequence approach by examining evolutionary questions with their off-target bycatch where possible-especially in cases where no previous mitochondrial data exists-but recommend stratifying data at different genome coverage thresholds to separate sampling effects from genuine genomic signals, and to understand their implications for evolutionary research.

Mitogenome-based phylogeny of mosquitoes (Diptera: Culicidae).

Mosquitoes are of great medical significance as vectors of many deadly diseases. Mitogenomes have been widely used in phylogenetic studies, but mitogenome knowledge within the family Culicidae is limited, and Culicidae phylogeny is far from resolved. In this study, we surveyed the mitogenomes of 149 Culicidae species, including 7 newly sequenced species. Comparative analysis of 149 mosquito mitogenomes shows gene composition and order to be identical to that of an ancestral insect, and the AT bias, length variation, and codon usage are all consistent with that of other reported Dipteran mitogenomes. Phylogenetic analyses based on the DNA sequences of the 13 protein-coding genes from the 149 species robustly support the monophyly of the subfamily Anophelinae and the tribes Aedini, Culicini, Mansoniini, Sabethini, and Toxorhynchitini. To resolve ambiguous relationships between clades within the subfamily Culicinae, we performed topological tests and show that Aedini is a sister to Culicini and that Uranotaeniini is a sister to (Mansoniini + (Toxorhynchitini + Sabethini)). In addition, we estimated divergence times using a Bayesian relaxation clock based on the sequence data and 3 fossil calibration points. The results show mosquitoes diverged during the Early Jurassic with massive Culicinae radiations during the Cretaceous, coincident with the emergence of angiosperms and the burst of mammals and birds. Overall, this study, which uses the largest number of Culicidae mitogenomes sequenced to date, comprehensively reveals the mitogenome characteristics and mitogenome-based phylogeny and divergence times of Culicidae, providing information for further studies on the mitogenome, phylogeny, evolution, and taxonomic revision of Culicidae.

Mitophylogeny of Pangasiid Catfishes and its Taxonomic Implications for Pangasiidae and the Suborder Siluroidei.

Pangasiidae (catfish order: Siluriformes) comprises 30 valid catfish species in four genera: Pangasius, Pangasianodon, Helicophagus, and Pseudolais. Their systematics are frequently revised due to the addition of newly described species. Although Pangasiidae is known to be a monophyletic family, the generic and phylogenetic relationships among the taxa are poorly resolved. This study characterized three newly obtained complete mitogenomes of Mekong River catfishes from Vietnam (Pangasius mekongensis, Pangasius krempfi, and Pangasianodon hypophthalmus), as well as the inter-and intrafamilial relationships of the Pangasiidae and catfish families in Siluroidei. The genomic features of their mitogenomes were similar to those of previously reported pangasiids, including all regulatory elements, extended terminal associated sequences (ETAS), and conserved sequence blocks (CSBs) (CSB-1, CSB-2, CSB-3, and CSBs, A to F) in the control region. A comprehensive phylogeny constructed from datasets of multiple 13 PCG sequences from 117 complete mitogenomes of 32 recognized siluriform families established Pangasiidae as monophyletic and a sister group of Austroglanididae. The [Pangasiidae + Austroglanididae] + (Ictaluridae + Cranoglanididae) + Ariidae] clade is a sister to the "Big Africa" major clade of Siluriformes. Furthermore, both phylogenies constructed from the single barcodes (83 partial cox1 and 80 partial cytB, respectively) clearly indicate genus relationships within Pangasiidae. Pangasianodon was monophyletic and a sister to the (Pangasius + Helicophagus + Pseudolais) group. Within the genus Pangasius, P. mekongensis was placed as a sister taxon to P. pangasius. Pangasius sanitwongsei was found to be related to and grouped with Pangasianodon, but in single-gene phylogenies, it was assigned to the Pangasius + Helicophagus + Pseudolais group. The datasets in this study are useful for studying pangasiid systematics, taxonomy and evolution.

Characterization of complete mitochondrial genome of three Horse flies of the genus Tabanus (Diptera: Tabanidae): comparative analysis.

BACKGROUND: Tabanidae (Horse-Flies or Deer-Flies) are one of the most economically important as well as medically significant haematophagous insect family within the order Diptera. Members of this group are also responsible for the mortality of substantial number of live-stock every year. Due to their pathogen transmission potential and vector competencies makes them an important insect group to study. Till now, mitochondrial genome of 18 species of tabanids were available. METHODS AND RESULTS: The complete mitogenome of three species T. diversifrons (15,809 bp), T. rubidus (15,878 bp) and T. tenens (15,872 bp) were generated by Next generation sequencing method. They consist 37 genes, with a positive AT skew and a negative GC skew. The gene order of these three species is similar to the typical gene arrangement of infra-order Tabanomorpha. Most of the tRNAs showed typical clover-leaf secondary structure except trnS1, which lacks the DHU arm. The sliding window analysis showed that the nad4L is the most conserved while atp8, and nad6 are the most variable genes. Moreover, the ratios of non-synonymous to synonymous substitution rates indicated that all PCGs under the purifying selection. Phylogeny revealed Chrysops and Haematopota are monophyletic while species of Hybomitra are nested within the polyphyletic clade of Tabanus. T. diversifrons exhibits sister relationship with Atylotus miser. Two morphologically divergent species T. rubidus and T. tenens are found to be genetically similar and indistinguishable by mitochondrial genome. CONCLUSIONS: The hypervariable genes like atp8 and nad6 can be used as molecular markers for the identification of recently diverged lineages of family Tabanidae. Further, to address uncertainties arising from the two morphological divergent species, it is imperative to obtain data from nuclear gene markers.

Characterization and Molecular Phylogenetic Analysis of Subfamily Erebinae (Lepidoptera: Noctuoidea: Erebidae) Using Five Complete Mitochondrial Genomes.

In this study, the complete mitogenomes of Sympis rufibasis, Lacera noctilio, Oxyodes scrobiculata, Mocis undata, and Artena dotata were newly sequenced to bring up-to-date the database using the next-generation sequencing methods. The gene order of all sequenced mitogenomes was identical consisting of 13 protein-coding genes (PCGs), 22 transfer RNA genes (tRNAs), two ribosomal RNA genes (rRNAs), and a non-coding A+T-rich region, which were common to other Lepidopteran insects. All protein-coding genes (PCGs) initiated with a canonical ATN codon and ended with TAN or an incomplete stop codon, single T. The A+T-rich region of S. rufibasis, L. noctilio, O. scrobiculata, M. undata, and A. dotata are 406 bp, 462 bp, 372 bp, 410 bp, and 406 bp long, respectively, containing number of characteristics that are distinctive to Noctuoidea moths. We analyzed concatenated amino acid sequences of protein-coding genes not including rRNAs, using Maximum Likelihood and Bayesian Inference methods. The phylogenetic analyses indicated that the tribe relationships within Erebinae were reconstructed as (Sypnini+((Erebini 1+Poaphilini 1)+((Euclidiini+Catocalini+(Hypopyrini+Erebini 2))+((Hulodini+(Poaphilini 2+Ophiusini))))). Phylogenetic analyses supported and confirmed the monophyly of the subfamilies' relationships as follows: (Hypeninae+Lymantriinae)+((Scoliopterginae+((Calpinae+Erebinae)+((Herminiinae+Aganainae)+Arctiinae)))) within Erebidae.

Novel genomic resources contribute to the systematics of threatened arboreal deer mice of the genus Habromys Hooper & Musser, 1964 (Cricetidae, Neotominae) within a neotomine-peromyscine phylogeny.

The Crested-tailed deer mouse, Habromyslophurus, is one of seven arboreal species within the genus Habromys. Species of this genus are monotypic, relatively rare, and occur in low densities. Their geographical distribution is highly fragmented due to being restricted to montane cloud forest in Mesoamerica and they are of conservation concern. All Habromys species are endemic to Mexico, except H.lophurus, which is also distributed in Guatemala and El Salvador. In this study, we obtained and characterized the first mitogenome and several thousand nuclear ultraconserved elements (UCEs) of H.lophurus to determine its phylogenetic position within neotomine-peromyscine mice. Its mitogenome sequence (16,509 bp) is only the second complete mitogenome obtained for this poorly known genus. We also obtained the first nuclear genomic data for H.lophurus, including 3,654 UCE loci, as well as a partial mitogenome of H.simulatus (6,349 bp), and 2,186 UCE for the outgroup Holochilussciureus. Phylogenetic analyses that included our newly generated genomic data coupled with previously published data from other neotomine-peromyscine mice confirm the placement of H.lophurus, H.simulatus, and H.ixtlani within a highly supported clade. The Habromys clade was nested within a clade that also contains members of the genus Peromyscus and provides further support for the hypothesis of the paraphyly of Peromyscus. These genomic resources will contribute to future phylogenomic studies that aim to further elucidate the evolutionary history of this rare and critically endangered genus of rodents.

The complete mitochondrial genomes of two imperiled species endemic to the Southwestern United States: Peppered Chub (Macrhybopsis tetranema) and Gila Trout (Oncorhynchus gilae).

Macrhybopsis tetranema and Oncorhynchus gilae are fish species endemic to the Southwestern United States. We present the complete mitochondrial genomes for these species. Each genome consisted of 13 protein-coding genes, two ribosomal (rRNA) genes, 22 transfer RNA (tRNA) genes, and the control region (D-loop). Mitogenome lengths were 16,916 base pairs (bp) for M. tetranema, and 16,976 bp for O. gilae. The GC content was 41% for M. tetranema and 46% for O. gilae. The relationships of M. tetranema and O. gilae were consistent with previous phylogenetic analyses.

Novel B2 mitogenomes from Continental southern Patagonia's Late Holocene: New insights into the peopling of the Southern Cone.

OBJECTIVES: The main aim of this study is to discuss the migratory processes and peopling dynamics that shaped the genetic variability of populations during the settlement of the Southern Cone, through the analysis of complete mitogenomes of individuals from southern Patagonia. MATERIALS AND METHODS: Complete mitogenomes were sequenced through massively parallel sequencing from two late Holocene individuals (SAC 1-1-3 and SAC 1-1-4) buried in the same chenque at Salitroso Lake Basin (Santa Cruz province, Argentina). To evaluate matrilineal phylogenetic affinities with other haplotypes, maximum likelihood and Bayesian phylogenetic reconstructions were performed, as well as a haplotype median-joining network. RESULTS: The mitogenomes were assigned to haplogroups B2 and B2b, exhibiting an average depth of 54X and 89X (≥1X coverage of 98.6% and 100%), and a high number of nucleotide differences among them. The phylogenetic analyses showed a relatively close relationship between the haplotype found in SAC 1-1-4 and those retrieved from a Middle Holocene individual from Laguna Chica (Buenos Aires province), and from a group of individuals from the Peruvian coast. For the SAC 1-1-3, no clear affiliations to any other haplotype were established. DISCUSSION: The large divergence between the haplotypes presented in this study suggests either a highly variable founder gene pool, or a later enrichment by frequent biological contact with other populations. Our results underline the persistence of genetic signals related to the first waves of peopling in South America, suggesting that the regional settlement of the southern end of the continent has been much more complex than initially thought.

OBJETIVOS: El objetivo principal de este estudio es discutir los procesos migratorios y la dinámica de poblamiento que moldearon la variabilidad genética de las poblaciones durante el poblamiento del Cono Sur, a través del análisis de mitogenomas completos de individuos del sur de Patagonia. MATERIALES Y MÉTODOS: Se obtuvieron mitogenomas completos mediante secuenciación masiva de dos individuos del Holoceno tardío (SAC 1-1-3 y SAC 1-1-4) enterrados en el mismo chenque en la Cuenca del Lago Salitroso (provincia de Santa Cruz, Argentina). Para evaluar las afinidades matrilineales con otros haplotipos, se realizaron reconstrucciones filogenéticas de máxima verosimilitud y bayesianas, así como una red mediana de haplotipos. RESULTADOS: Los mitogenomas fueron asignados a los haplogrupos B2 y B2b, exhibiendo una profundidad de secuenciación promedio de 54X y 89X (cobertura ≥1X de 98,6% y 100%), y un elevado número de diferencias nucleotídicas entre ellos. Los análisis filogenéticos mostraron una relación relativamente estrecha entre el haplotipo encontrado en el SAC 1-1-4 y los recuperados de un individuo del Holoceno Medio de Laguna Chica (provincia de Buenos Aires), y de un grupo de individuos de la costa peruana. Para el SAC 1-1-3, no se establecieron relaciones claras con ningún otro haplotipo. DISCUSIÓN: La gran divergencia entre los haplotipos presentados en este estudio sugiere gran variabilidad en el acervo genético fundador, o bien un enriquecimiento posterior por contacto biológico frecuente con otras poblaciones. Nuestros resultados destacan la persistencia de señales genéticas relacionadas con las primeras oleadas de poblamiento de Sudamérica, lo que sugiere que el poblamiento regional del extremo sur del continente ha sido mucho más complejo de lo que se pensaba inicialmente.

Crossing the Rift valley: using complete mitogenomes to infer the diversification and biogeographic history of ethiopian highlands Ptychadena (anura: Ptychadenidae).

The Ethiopian Highlands are considered a biodiversity hotspot, harboring a high number of endemic species. Some of the endemic species probably diversified in situ; this is, for example, the case of a monophyletic clade containing 12 known species of grass frogs of the genus Ptychadena. The different species occur at elevations ranging from 1,500 to above 3,400 m and constitute excellent models to study the process of diversification in the highlands as well as adaptations to high elevations. In this study, we sampled 294 specimens across the distribution of this clade and used complete mitogenomes and genome-wide SNP data to better understand how landscape features influenced the population structure and dispersal of these grass frogs across time and space. Using phylogenetic inference, population structure analyses, and biogeographic reconstructions, we found that the species complex probably first diversified on the south-east side of the Great Rift Valley. Later on, species dispersed to the north-west side, where more recent diversification occurred. We further demonstrate that Ptychadena species have dispersed across the Great Rift Valley at different times. Our analyses allowed for a more complete understanding of the contribution of geological events, biogeographic barriers and climatic changes as drivers of species diversification and adaptation in this important biogeographic region.

The complete mitochondrial genome of Anthrenus museorum (Coleoptera: Bostrichiformia: Dermestidae) from China.

Dermestid beetles (Coleoptera: Bostrichiformia: Dermestidae) are important pests of various storage products and pose a potential threat to international trade. In this study, the whole mitogenome of Anthrenus museorum was first sequenced and annotated and was found to have the same gene order observed in known dermestid beetles. It comprised 13 protein-coding genes (PCGs), 22 transfer RNAs, 2 ribosomal RNAs and a control region. The typical ATN start codon was observed in all PCGs, except for ND3 (TTG), and all 13 PCGs showed three types of stop codons (TAA, TAG, and T-). Phylogenetic analysis based on the PCGs indicated that the relationships within Bostrichiformia were reconstructed, with the exception of one early emerging species of Bostrichidae that actually makes the group polyphyletic, as (Dermestidae + (Bostrichidae + Anobiidae)). Moreover, it revealed a close relationship between A. museorum and A. verbasci using maximum likelihood and Bayesian inference analysis.

A complete species-level phylogeny of the Erythrura parrotfinches (Aves: Estrildidae).

Identifying species boundaries and phylogenetic relationships among groups of closely related species provides a necessary framework for understanding how biodiversity evolves in natural systems. Here we present a complete phylogeny of the avian genus Erythrura (family Estrildidae) commonly known as parrotfinches, which includes species threatened by habitat loss and the pet trade. Using both mitogenome and reduced-representation genome-wide nuclear DNA sequence data, we reconstructed the evolutionary history of the group by sampling all 12 recognized species, four of which had not previously been studied in a phylogenetic context. We included intra-species geographic sampling that allowed us to comment on species limits in some taxa. We recovered the Gouldian Finch (Chloebia gouldiae) of Australia which has often been placed in the monotypic genus Chloebia, as being sister to a clade comprising all Erythrura species. In addition, we recovered a well-supported clade comprising eight species distributed throughout the Pacific Island eco-region, whereas those species occurring in continental southeast Asia, the Greater Sundas, and the Philippines, were recovered as earlier branching lineages. Of note was the early branching of the Fiji-endemic E. kleinschmidti which corroborates its unique phenotype. We also found a deep phylogenetic split (8.59% corrected, 7.89% uncorrected divergence in the mitochondrial gene ND2) between the Java and Philippine populations of E. hyperythra, indicating unrecognized species-level diversity within this taxon. In contrast, genome-wide nuclear data suggested that the New Guinea endemic species E. papuana is embedded within the widespread species E. trichroa in all phylogenetic reconstructions, corroborating previously published mitochondrial data that suggested a similar pattern. By generating a phylogenetic hypothesis for the relationships among all species of Erythrura parrotfinches, we provide a framework for better understanding the extant diversity and evolutionary history of this group.

Two New Mitogenomes of Bibionidae and Their Comparison within the Infraorder Bibionomorpha (Diptera).

Despite the worldwide distribution and rich diversity of the infraorder Bibionomorpha in Diptera, the characteristics of mitochondrial genomes (mitogenomes) are still little-known, and the phylogenetics and evolution of the infraorder remains controversial. In the present study, we report complete and annotated mitogenome sequences of Penthetria simplioipes and Plecia hardyi representing Bibionidae. This is the first report of the complete mitogenomes for the superfamily Bibionoidea. There are 37 genes in each of the complete mitogenomes of all 20 studied species from eight families of four superfamilies within infraorder Bibionomorpha. The Ka/Ks analysis suggests that all 13 PCGs have undergone purifying selection. The gene rearrangement events exist in some families (Keroplatidae, Sciaridae, and Cecidomyiidae) but not in Mycetophilidae in Sciaroidea and also in Scatopsoidea, Anisopodoidea, and Bibionoidea, which suggests that these rearrangement events are derived in the late period in the evolution of the Bibionomorpha. The phylogenetic analysis suggests the phylogenetic relationships of Scatopsoidea + (Anisopodoidea + (Bibionoidea + Sciaroidea)) in Bibionomorpha. The divergence time analysis suggests that Bibionomorpha originated in the Triassic, Scatopsoidea and Anisopodoidea in the late Triassic, Bibionoidea in the Jurassic, and Sciaroidea in the Jurassic to the Cretaceous. The work lays a base for the study of mitogenomes in Bibionomorpha but further work and broader taxon sampling are necessary for a better understanding of the phylogenetics and evolution of the infraorder.

Mitogenome Characterization of Four Conus Species and Comparative Analysis.

Cone snails, as a type of marine organism, have rich species diversity. Traditionally, classifications of cone snails were based mostly on radula, shell, and anatomical characters. Because of these phenotypic features' high population variability and propensity for local adaptation and convergence, identifying species can be difficult and occasionally inaccurate. In addition, mitochondrial genomes contain high phylogenetic information, so complete mitogenomes have been increasingly employed for inferring molecular phylogeny. To enrich the mitogenomic database of cone snails (Caenogastropoda: Conidae), mitogenomes of four Conus species, i.e., C. imperialis (15,505 bp), C. literatus (15,569 bp), C. virgo (15,594 bp), and C. marmoreus (15,579 bp), were characterized and compared. All 4 of these mitogenomes included 13 protein-coding genes, 2 ribosomal RNA genes, 22 tRNA genes, and non-coding regions. All the Protein Codon Genes (PCGs) of both newly sequenced mitogenomes used TAA or TAG as a terminal codon. Most PCGs used conventional start codon ATG, but an alternative initiation codon GTG was detected in a gene (NADH dehydrogenase subunit 4 (nad4)) of C. imperialis. In addition, the phylogenetic relationships were reconstructed among 20 Conus species on the basis of PCGs, COX1, and the complete mitogenome using both Bayesian Inference (BI) and Maximum Likelihood (ML). The phylogenetic results supported that C. litteratus, C. quercinus, and C. virgo were clustered together as a sister group (PP = 1, BS = 99), but they did not support the phylogenetic relation of C. imperialis and C. tribblei (PP = 0.79, BS = 50). In addition, our study established that PCGs and complete mitogenome are the two useful markers for phylogenetic inference of Conus species. These results enriched the data of the cone snail's mitochondrion in the South China Sea and provided a reliable basis for the interpretation of the phylogenetic relationship of the cone snail based on the mitochondrial genome.