Description of a new Ornithodoros (Pavlovskyella) (Ixodida: Argasidae) tick species from Pakistan.

The genus Ornithodoros is notably diverse within the family Argasidae, comprising approximately 134 species distributed among 4 subgenera, 1 of which is the subgenus Pavlovskyella. In an earlier study, we identified distinct soft ticks as Ornithodoros (Pavlovskyella) sp., which were collected from animal shelters in Khyber Pakhtunkhwa, Pakistan. Providing additional collections from that same locality and a comprehensive analysis involving detailed morphological and mitogenome-based comparisons with closely related species, this study formally designates a novel species for these specimens. Adults and late-instar nymphs of the new species display a dorsoventral groove, small cheeks not covering the capitulum, 5 small even humps on tarsus I and a transverse postanal groove intersecting the median postanal groove perpendicularly. It also lacks a tuft of setae on the ventral surface of the hood which separates the novel species from Ornithodoros papillipes. Ventral chaetotaxy of tarsus IV indicates 4­7 setal pairs in nymphs and 5­7 pairs in adults that separate the new species from Ornithodoros tholozani sensu stricto and Ornithodoros crossi, 2 morphologically closely related species that occur in geographical proximity. Phylogenetic analyses of the full-length mitochondrial genome and the 18S and 28S ribosomal RNA genes, combined with pairwise nucleotide comparisons of cox1, cox2, atp8, atp6, cox3, nad3, nad5, nad4, nad4L, nad6, cytb, nad1, nad2, 12S rDNA, 16S rDNA, 18S rDNA and 28S rDNA further support that the new species belongs to the Pavlovskyella subgenus, clustering with O. tholozani, Ornithodoros verrucosus and Ornithodoros tartakovskyi.

Museum specimens shedding light on the evolutionary history and cryptic diversity of the hedgehog family Erinaceidae.

The family Erinaceidae encompasses 27 extant species in two subfamilies: Erinaceinae, which includes spiny hedgehogs, and Galericinae, which comprises silky-furred gymnures and moonrats. Although they are commonly recognized by the general public, their phylogenetic history remains incompletely understood, and several species have never been included in any molecular analyses. Additionally, previous research suggested that the species diversity of Erinaceidae might be underestimated. In this study, we sequenced the mitochondrial genomes of 29 individuals representing 18 erinaceid species using 18 freshly collected tissue and 11 historical museum specimens. We also integrated previously published data for a concatenated analysis. We aimed to elucidate the evolutionary relationships within Erinaceidae, estimate divergence times, and uncover potential underestimated species diversity. Our data finely resolved intergeneric and interspecific relationships and presented the first molecular evidence for the phylogenetic position of Mesechinus wangi, Paraechinus micropus, and P. nudiventris. Our results revealed a sister relationship between Neotetracus and Neohylomys gymnures, as well as a sister relationship between Hemiechinus and Mesechinus, supporting previous hypotheses. Additionally, our findings provided a novel phylogenetic position for Paraechinus aethiopicus, placing it in a basal position within the genus. Furthermore, our study uncovered cryptic species diversity within Hylomys suillus as well as in Neotetracus sinensis, Atelerix albiventris, P. aethiopicus, and Hemiechinus auratus, most of which have been previously overlooked.

Complete Mitochondrial Genome of Tanypus chinensis and Tanypus kraatzi (Diptera: Chironomidae): Characterization and Phylogenetic Implications.

BACKGROUND: Chironomidae occupy a pivotal position within global aquatic ecosystems. The unique structural attributes of the mitochondrial genome provide profound insights and compelling evidence, underpinning the morphological classification of organisms and substantially advancing our understanding of the phylogenetic relationships within Chironomidae. RESULTS: We have meticulously sequenced, assembled, and annotated the mitogenomes of Tanypus chinensis (Wang, 1994) and Tanypus kraatzi (Kieffer, 1912), incorporating an additional 25 previously published mitogenomes into our comprehensive analysis. This extensive dataset enables us to delve deeper into the intricate characteristics and nuances of these mitogenomes, facilitating a more nuanced understanding of their genetic makeup. CONCLUSIONS: The genomic nucleotide composition of T. kraatzi was 39.10% A, 36.51% T, 14.33% C, and 10.06% G, with a total length of 1508 bp. The genomic nucleotide composition of T. chinensis was 39.61% A, 36.27% T, 14.55% C, and 9.57% G, with a total length of 1503 bp. This significant enrichment of the chironomid mitogenome library establishes a novel foundation for further exploration in the realm of phylogenetics.

New insights into the phylogenetic relationships within the Lauraceae from mitogenomes.

BACKGROUND: The family Lauraceae is subdivided into six main lineages: Caryodaphnopsideae, Cassytheae, Cryptocaryeae, Hypodaphnideae, Laureae, and Neocinnamomeae. However, phylogenetic relationships among these lineages have been debatable due to incongruence between trees constructed using nuclear ribosomal DNA (nrDNA) sequences and chloroplast (cp) genomes. As with cp DNA, the mitochondrial (mt) DNA of most flowering plants is maternally inherited, so the phylogenetic relationships recovered with mt genomes are expected to be consistent with that from cp genomes, rather than nrDNA sequences. RESULTS: The mitogenome of Machilus yunnanensis, with a length of 735,392 bp, has a very different genome size and gene linear order from previously published magnoliid mitogenomes. Phylogenomic reconstructions based on 41 mt genes from 92 Lauraceae mitogenomes resulted in highly supported relationships: sisterhood of the Laureae and a group containing Neocinnamomeae and Caryodaphnopsideae, with Cassytheae being the next sister group, followed by Cryptocaryeae. However, we found significant incongruence among the mitochondrial, chloroplast, and nuclear phylogenies, especially for the species within the Caryodaphnopsideae and Neocinnamomeae lineages. Time-calibrated phylogenetic analyses showed that the split between Caryodaphnopsideae and Neocinnamomeae dated to the later Eocene, around 38.5 Ma, Laureae originated in the Late Cretaceous, around 84.9 Ma, Cassytheae originated in the mid-Cretaceous around 102 Ma, and Cryptocaryeae originated in the Early Cretaceous around 116 Ma. From the Late Cretaceous to the Paleocene, net diversification rates significantly increased across extant clades of major lineages, and both speciation rates and net diversification rates continued steady growth towards the present. CONCLUSIONS: The topology obtained here for the first time shows that mt genes can be used to support relationships among lineages of Lauraceae. Our results highlight that both Caryodaphnopsideae and Neocinnamomeae lineages are younger than previously thought, likely first diversifying in the Eocene, and species in the other extant lineages of Lauraceae dates in a long-time span from the Early Cretaceous to the Eocene, and the climate of a period of about 90 million years was relatively warm, while the extant species of Lauraceae then continuously diversified with global cooling from the Eocene to the present day.

The complete mitochondrial genome and phylogenetic analysis for Rhabdophis chiwen (squamata: colubridae).

Rhabdophis chiwen is currently found so far in Sichuan Province, China, where it predominantly feeds on earthworms and firefly larvae. In this study, we sequenced and analyzed the mitochondrial genome of R. chiwen, which measured 17,646 bp in length and encompassed 37 genes along with two control regions. The base composition revealed percentages of 33.20% A, 25.94% T, 13.27% G, and 27.59% C. Phylogenetic analyses indicate that R. chiwen belongs to the family Colubridae and forms a sister branch with R. tigrinus. This study successfully obtained the first complete mitochondrial genome of R. chiwen, offering crucial genetic data for its evolutionary history and conservation.

Mitochondrial genome of the Indian spot-billed duck and its phylogenetic and conservation implications.

The Indian spot-billed duck, Anas poecilorhyncha is a large dabbling and non-migratory breeding bird. The identification and phylogenetic relationship of A. poecilorhyncha remain uncertain due to the presence of overlapping meristic characters and hybridization with closely related species. Molecular data aids when there are challenges in morphological identification. However, genetic characterization of A. poecilorhyncha has been paid less attention. Apart from their functional and physiological role, mitochondrial genome can also be used for various purposes, including species identification, phylogenetic analysis, understanding the domestication history of species etc. Therefore, the present study aimed to sequence the mitochondrial genome of A. poecilorhyncha and its closely related domestic species A. platyrhynchos (mallard duck) to understand their mitochondrial genome structure and phylogenetic relationships. The length of mitochondrial genome of A. poecilorhyncha and A. platyrhynchos was 16,608 and 16,604 bp respectively. Mitochondrial genome contained 37 genes and a non-coding control region. Overall, the characteristics of mitochondrial genome of both species were found to be conserved. The phylogenetic tree exhibited seven major clades (A to G) with a high bootstrap support. Notably, the Indian A. poecilorhyncha population formed a distinct clade (C) whereas the A. poecilorhyncha that were probably sampled from China grouped along with A. zonorhyncha (clade B). Besides, one of the A. poecilorhyncha probably sampled from China was placed in the clade A, which predominantly consisted of A. platyrhynchos. It suggests that Indian A. poecilorhyncha population is genetically different from Chinese A. poecilorhyncha population. Further, it sheds light on the importance of conducting a comprehensive phylogenetic study on these species. The newly sequenced mitochondrial genome of A. poecilorhyncha and A. platyrhynchos would be useful not only to have a better understanding of the phylogeny and evolution of Anas species but also to help in the conservation of A. poecilorhyncha which is under constant threat from rapid urbanization, interspecific hybridization and other human activities.

The complete mitochondrial genome of Castanopsis carlesii and Castanea henryi reveals the rearrangement and size differences of mitochondrial DNA molecules.

BACKGROUND: Castanopsis carlesii is a dominant tree species in subtropical evergreen broad-leaved forests and holds significant ecological value. It serves as an excellent timber tree species and raw material for cultivating edible fungi. Henry Chinquapin (Castanea henryi) wood is known for its hardness and resistance to water and moisture, making it an exceptional timber species. Additionally, its fruit has a sweet and fruity taste, making it a valuable food source. However, the mitogenomes of these species have not been previously reported. To gain a better understanding of them, this study successfully assembled high-quality mitogenomes of C. carlesii and Ca. henryi for the first time. RESULTS: Our research reveals that the mitochondrial DNA (mtDNA) of C. carlesii exhibits a unique multi-branched conformation, while Ca. henryi primarily exists in the form of two independent molecules that can be further divided into three independent molecules through one pair of long repetitive sequences. The size of the mitogenomes of C. carlesii and Ca. henryi are 592,702 bp and 379,929 bp respectively, which are currently the largest and smallest Fagaceae mitogenomes recorded thus far. The primary factor influencing mitogenome size is dispersed repeats. Comparison with published mitogenomes from closely related species highlights differences in size, gene loss patterns, codon usage preferences, repetitive sequences, as well as mitochondrial plastid DNA segments (MTPTs). CONCLUSIONS: Our study enhances the understanding of mitogenome structure and evolution in Fagaceae, laying a crucial foundation for future research on cell respiration, disease resistance, and other traits in this family.

Unraveling the Mitogenomic Characteristics and Phylogenetic Implications of Leuciscus merzbacheri (Zugmayer, 1912), an Endangered Fish in the Junggar Basin of Xinjiang, Northwest China.

BACKGROUND: Leuciscus merzbacheri is a rare and endangered fish in Xinjiang, China. As a representative species of the fauna in the Junggar Basin, it is of high economic and scientific value. The genetic data are still limited, and the mitochondrial genomic characteristics remain unexplored. METHODS: A high-throughput sequencing method was used to obtain the complete mitogenome of L. merzbacheri. RESULTS: The full length of the circular DNA was 16,609 bp, and it consisted of 13 protein-coding genes (PCGs), 22 tRNAs, 2 rRNAs and 2 non-coding regions. The overall nucleotide compositions of both the mitogenome and PCGs showed an obvious AT preference with percentages of 54.20% and 53.60%, respectively. Three commonly used amino acids were Leu (16.43%), Ala (8.95%) and Thr (7.85%) in turn. All tRNAs could form the typical clover structures excluding tRNA-Ser AGY. The presumed secondary structures of two rRNAs contained several stem-loop domains, and the structure of 12S rRNA seemed to be more stable than that of 16S rRNA. Extended termination sequence regions (ETASs), central conserved regions (CSB-F, CSB-E and CSB-D), and conserved sequence regions (CSB-1, CSB-2 and CSB-3) were identified in the control region. The phylogenetic tree showed that L. merzbacheri was recovered with strong supports as a sister to the other members of the genus. The location in the outermost branch implied that it might be a relatively ancient species among its congeners. CONCLUSIONS: This study would complement the genetic data on L. merzbacheri and contribute to a better understanding of molecular evolution in Leuciscus as well.

Genetic Insights into the Giant Keyhole Limpet (Megathura crenulata), an Eastern Pacific Coastal Endemic: Complete Mitogenome, Phylogenetics, Phylogeography, and Historical Demography.

BACKGROUND: The giant keyhole limpet Megathura crenulata is a gastropod mollusk (Fissurella superfamily) that is endemic to the eastern Pacific coast from southern California, USA, to Baja California Sur, Mexico. M. crenulata is socioeconomically important as it produces a potent immune-stimulating protein, called Keyhole Limpet Hemocyanin, which is extracted in vivo and utilized for vaccine development. However, ecological studies are scarce and genetic knowledge of the species needs to be improved. Our objectives were to assemble and annotate the mitogenome of M. crenulata, and to assess its phylogenetic relationships with other marine gastropods and to evaluate its population genetic diversity and structure. METHODS: Samples were collected for mitogenome assembly (n = 3) spanning its geographic range, Puerto Canoas (PCA) and Punta Eugenia (PEU), Mexico, and California (CAL), USA. Total DNA was extracted from gills sequenced using Illumina paired-end 150-bp-read sequencing. Reads were cleaned, trimmed, assembled de novo, and annotated. In addition, 125 samples from eight locations were analyzed for genetic diversity and structure analysis at the 16s rRNA and COX1 genes. RESULTS: The M. crenulata mitogenomes had lengths of 16,788 bp (PCA) and 16,787 bp (PEU) and were composed of 13 protein-coding regions, 22 tRNAs, two rRNAs, and the D-Loop region. In terms of phylogeographic diversity and structure, we found a panmictic population that has experienced recent demographic expansion with low nucleotide diversity (0.002), high haplotypic diversity (0.915), and low φST (0.047). CONCLUSIONS: Genetic insights into the giant keyhole limpet provides tools for its management and conservation by delimiting fishing regions with low genetic diversity and/or genetically discrete units.

Three Mitochondrial Genomes of Chrysochroinae (Coleoptera, Buprestidae) and Phylogenetic Analyses.

Three mitochondrial genomes of Chrysochroinae (Buprestidae) were sequenced and analyzed. The mitogenomes of the genera Catoxantha and Nipponobuprestis are first reportedand Chrysochroa opulenta is a first record for China. The complete mitogenomes of Catoxantha luodiana, Nipponobuprestis guangxiensis and Chrysochroa opulenta exhibit striking similarities in their lengths and composition. Specifically, their lengths are 15,594 bp, 15,775 bp and 15,587 bp, respectively. Each of these genomes encodes 37 typical mitochondrial genes. The overwhelming majority of protein-coding genes (PCGs) have the typical ATN (ATT, ATA, ATG or ATC) as the start codon and terminate with TAR (TAA or TAG) as the stop codon or an incomplete stop codon T-. Among the three mitogenomes, Leu2, Ser2 and Phe were the most frequently encoded amino acids. In the PCGs, the Ka/Ks ratio of cox1 is the lowest, whereas atp6 has the highest value. This suggests that cox1 can be used as a molecular barcode for species delimitation and phylogeny in Chrysochroinae. The phylogenetic results showed that C. luodiana and two Chrysochroa species formed a clade. Based on the topology of the phylogenetic tree, the genus Catoxantha should be reassigned as a subgenus of Chrysochroa.

The complete mitochondrial genome of Parotis chlorochroalis (Hampson, 1912) (Lepidoptera: Crambidae).

The complete mitochondrial genome of the Parotis chlorochroalis was sequenced, revaeling a length of 15239 bp with 37 genes and an A + T-rich region. All c13 PCGs begin with typical ATN codons, except COI gene, which starts with CGA. Eleven genes terminate with TAA, two with T-. All 22 tRNA genes exhibit typical cloverleaf structure except for trnS1 P. chlorochroalis has two relatively conserved intergenic regions and two relatively conserved overlapping regions. Phylogenetic analysis support P. chlorochroalis belongs to subfamily Spilomelinae, the topologies of Crambidae are highly congruent with previous studies. This newly sequences mitochondrial genome provides valuable resources for taxonomic inference and evolutionary studies of genus Parotis.

The complete mitogenome of Alternaria tenuissima (Kunze) Wiltshire 1933 (Pleosporaceae), a fungus causing apple leaf blotch disease.

Alternaria tenuissima (Kunze) Wiltshire 1933 is a plant pathogenic fungus mainly causing leaf blotch disease. Here, we de novo assembled mitochondrial genome of A. tenuissima isolate AT-1224. The total mitogenome size is 57,475 bp with 29.00% G + C content. The genome contained 12 coding genes and 15 hypothetical proteins, 34 transfer RNA (tRNA) genes and 2 ribosomal RNA (rRNA). There are 227 SSR repeats, range from 2 to 4 base pairs, most five repeats were AT (144), AAT (54), AG (33), AC (13) and AAG (5). The results also found 13 tandem repeats (>100 bp), the largest repeat were forward 2 times located from 13,405 to 20,024 bp and 25,549 to 32,168 bp. Phylogenetic analysis based on 17 species complete mitogenomes indicated that A. tenuissima mitogenome was closest to 2 species, A. solani and A. alternata, sister clade to 6 species, representing Curvularia clavate, Exserohilum rostratum, Exserohilum turcicum, Bipolaris cookie, Bipolaris oryzae and Bipolaris sorokiniana. Further analysis among common fungus in local apple orchards using mitochondrial protein-coding genes revealed A. tenuissima were closing to 2 Alternaria fungi and a fungus representing Phoma sp. These results provide a basic reference for identification and evolution studies of A. tenuissima on apple trees.

Sympatric diversity pattern driven by the secondary contact of two deeply divergent lineages of the soybean pod borer Leguminivora glycinivorella.

The soybean pod borer, Leguminivora glycinivorella (Matsumura), is an important tortricid pest species widely distributed in most parts of China and its adjacent regions. Here, we analyzed the genetic diversity and population differentiation of L. glycinivorella using diverse genetic information including the standard cox1 barcode sequences, mitochondrial genomes (mitogenomes), and single-nucleotide polymorphisms (SNPs) from genotyping-by-sequencing. Based on a comprehensive sampling (including adults or larvae of L. glycinivorella newly collected at 22 of the total 30 localities examined) that covers most of the known distribution range of this pest, analyses of 543 cox1 barcode sequences and 60 mitogenomes revealed that the traditionally recognized and widely distributed L. glycinivorella contains two sympatric and widely distributed genetic lineages (A and B) that were estimated to have diverged ∼1.14 million years ago during the middle Pleistocene. Moreover, low but statistically significant correlations were recognized between genetic differentiation and geographic or environmental distances, indicating the existence of local adaptation to some extent. Based on SNPs, phylogenetic inference, principal component analysis, fixation index, and admixture analysis all confirm the two divergent sympatric lineages. Compared with the stable demographic history of Lineage B, the expansion of Lineage A had possibly made the secondary contact of the two lineages probable, and this process may be driven by the climate fluctuation during the late Pleistocene as revealed by ecological niche modeling.

The Complete Mitochondrial Genomes of Penthe kochi (Coleoptera: Tetratomidae) with Its Phylogenetic Implications.

To explore the mitogenome characteristics of Tetratomidae and the phylogenetic position of this family in Tenebrionoidea, the mitogenome of Penthe kochi Maran, 1940 was sequenced, annotated, and analyzed. The P. kochi mitogenome is consistent with Tenebrionoidea species in gene length, genomic organization, codon usage, and secondary structures of transfer genes (tRNAs). Most protein-coding genes (PCGs) originate with a typical ATN start codon, except nad1 and nad3, which start with TTG. In total, 10 PCGs are terminated with complete stop codon TAA and TAG, while cox1, cox2, and nad 4 contain an incomplete stop codon T-. Among the 13 PCGs, nad2 (Pi = 0.282) has the most diverse nucleotide composition, and cox2 is the most conserved gene with the lowest value (Pi = 0.154). The Ka/Ks ratio of cox1 (0.076) and cox2 (0.124) has a lower value. All the tRNAs can be folded in a typical clover-leaf secondary structure, except trnS1, which lacked a dihydrouridine arm. And phylogenetic analyses were performed based on 13 PCGs using the Bayesian inference (BI) method. The results showed that the clade of Tenebrionoidea was well separated from the outgroups, and Tetratomidae and Mycetophagidae were not well resolved. Phylogenetic analyses with more mitogenome samplings are needed to resolve the phylogeny of Tenebrionoidea.

Mitochondrial Phylogenomics of Scoliidae from China, with Evidence to Challenge the Former Placement of the Colpa Group.

Scoliidae, also known as scarab hunters or flower wasps, are important in the biological control of scarabs and for pollination. Mitogenomic and phylogenetic studies are rare for this group. In this study, 10 mitochondrial genomes representing eight genera in two tribes of the family Scoliidae were determined. The general features and rearrangements of the mitochondrial genomes for 15 Scoliidae species representing all genera distributed in China were described and compared and the phylogenetic relationships among them were inferred using MrBayes and IQtree based on four data matrices. Most sequences of Scoliidae have one extra trnM gene. Species belonging to Campsomerini have lower A + T content than all Scoliini species except for Colpa tartara in this study. The AT-skew is positive in 7 out of 15 species. All 15 Scoliidae sequences have similar conserved gene arrangements with the same arrangements of PCGs and rRNA genes, except for Campsomeriella annulata. The tRNA genes have the highest frequency of rearrangement, and C. tartara is always rearranged as in its Scoliini counterparts. Our phylogenetic results support most of the relationships between genera and tribes of Scoliidae in former morphological studies. However, Colpa tartara is proved to be closer to Scoliini according to genome features, phylogenetic analyses and some morphological evidence, which challenges the former attribution of the Colpa group.

Metacollinia emscheri n. sp., a novel sanguicolous apostome ciliate of freshwater amphipods (Gammarus spp.).

We describe a novel sanguicolous parasitic ciliate, Metacollinia emscheri n. sp., found in the freshwater amphipods Gammarus pulex and G. fossarum. This ciliate infected 8.05 % of the amphipods collected in a German stream catchment, the Boye, a tributary of the river Emscher. The ciliate showed morphological characteristics fitting the genus Metacollinia. Different life stages of variable size occurred simultaneously in the hemocoel throughout the hosts' body. The tomont had 40-47 slightly spiraled kineties, a non-ciliated cortical band, a large macronucleus, and contractile vacuoles arranged in rows or scattered throughout the cytoplasm. The protomites/tomites with nine somatic kineties presented evidence of the buccal kineties x, y, and z reminiscent of those of the order Foettingeriida. Phylogenetic analyses of the 18S rRNA and COI regions confirm the ciliate placement in the Collinidae and a close relatedness to the type species of the genus Metacollinia, Metacollinia luciensis. We formally describe this new parasite as Metacollinia emscheri n. sp. using pathological, morphological, and nuclear/mitochondrial genetic data. The systemic infections observed in histological preparations and the pathogenicity of Metacollinia emscheri n. sp. suggest that this parasite might influence host population dynamics. Given the ecological importance of amphipods as keystone species in freshwater ecosystems, an outbreak of this parasite might indirectly impact ecosystem functioning.

De novo assembly and characterization of the complete mitochondrial genome of Phellodendron amurense reveals three repeat-mediated recombination.

Phellodendron amurense Rupr., a rare herb renowned for its medicinal and ecological significance, has remained genetically unexplored at the mitochondrial level until now. This study presents the first-ever systematic assembly and annotation of the complete mitochondrial genome of P. amurense, achieved through a hybrid strategy combining Illumina and Nanopore sequencing data. The mitochondrial genome spans 566,285 bp with a GC content of 45.51 %, structured into two circular molecules. Our comprehensive analysis identified 32 protein-coding genes (PCGs), 33 tRNA genes, and 3 rRNA genes, alongside 181 simple sequence repeats, 19 tandem repeats, and 310 dispersed repeats. Notably, multiple genome conformations were predicted due to repeat-mediated homologous recombination. Additionally, we assembled the chloroplast genome, identifying 21 mitochondrial plastid sequences that provide insights into organelle genome interactions. A total of 380 RNA-editing sites within the mitochondrial PCGs were predicted, enhancing our understanding of gene regulation and function. Phylogenetic analysis using mitochondrial PCGs from 30 species revealed evolutionary relationships, confirming the homology between P. amurense and Citrus species. This foundational study offers a valuable genetic resource for the Rutaceae family, facilitating further research into genetic evolution and molecular diversity in plant mitochondrial genomes.

The mitochondrial genome sequences of eleven leafhopper species of Batracomorphus (Hemiptera: Cicadellidae: Iassinae) reveal new gene rearrangements and phylogenetic implications.

Batracomorphus is the most diverse and widely distributed genus of Iassinae. Nevertheless, there has been no systematic analysis of the genome structure and phylogenetic relationships of the genus. To determine the characteristics of the mitogenomes of Batracomorphus species as well as the phylogenetic relationships between them, we sequenced and compared the mitogenomes of 11 representative Batracomorphus species. The results revealed that the mitogenomes of the 11 Batracomorphus species exhibited highly similar gene and nucleotide composition, and codon usage compared with other reported mitogenomes of Iassinae. Of these 11 species, we found that the mitogenomes of four species were rearranged in the region from trnI-trnQ-trnM to trnQ-trnI-trnM, whereas the remaining species presented a typical gene order. The topologies of six phylogenetic trees were in agreement. Eurymelinae consistently formed paraphyletic groups. Ledrinae and Evacanthinae formed sister taxa within the same clade. Similarly, Typhlocybinae and Mileewinae consistently clustered together. All phylogenetic trees supported the monophyly of Iassinae, indicating its evolutionary distinctiveness while also revealing its sister relationship with Coelidiinae. Notably, the nodes for all species of the genus Batracomorphus were well supported and these taxa clustered into a large branch that indicated monophyly. Within this large branch, four Batracomorphus species with a gene rearrangement (trnQ-trnI-trnM) exhibited distinctive clustering, which divided the large branch into three minor branches. These findings expand our understanding of the taxonomy, evolution, genetics, and systematics of the genus Batracomorphus and broader Iassinae groups.

Characterization of the complete mitochondrial genome of the Sunda stink-badger (Mydaus javanensis) from the island of Borneo.

Background: The Mephitidae is a family of skunks and stink-badgers that includes 12 extant species in four genera, namely, Mydaus, Conepatus, Mephitis and Spilogale. Mydaus is the only genus within Mephitidae found outside the American continent, with its distribution limited to the islands of Borneo, Indonesia and Philippines. There are two extant species of Mydaus i.e., javanensis and marchei. Currently, complete mitogenomes are unavailable for either species. Here, we present the characterization of the first complete mitogenome for the Sunda stink-badger (Mydaus javanensis) from the island of Borneo. Methods: Muscle tissue was obtained and the DNA was sequenced using a combination of Illumina Barcode Tagged Sequence (BTSeq) and Sanger sequencing techniques. The genome was annotated with MITOS and manually checked for accuracy. A circular map of the mitogenome was constructed with Proksee. Relative synonymous codon usage (RSCU) and codon frequency were calculated using MEGA-X. The protein coding genes (PCGs) were aligned with reference sequences from GenBank and used for the construction of phylogenetic trees (maximum liklihood (ML) and Bayesian inference (BI)). Additionally, due to the lack of available complete genomes in public databases, we constructed another tree with the cyt b gene. Results: The complete circular mitogenome was 16,391 base pairs in length. It comprises the typical 13 protein-coding genes, 22 tRNAs, two ribosomal RNA genes, one control region (CR) and an L-strand replication origin (OL). The G+C content was 38.1% with a clear bias towards A and T nucleotides. Of the 13 PGCs, only ND6 was positioned in the reverse direction, along with five other tRNAs. Five PCGs had incomplete stop codons and rely on post-transcriptional polyadenylation (TAA) for termination. Based on the codon count, Leucine was the most common amino acid (589), followed by Threonine (332) and Isoleucine (325). The ML and BI phylogenetic trees, based on concatenated PCGs and the cyt b gene, respectively, correctly clustered the species with other members of the Mephitidae family but were unique enough to set it apart from Conepatus, Mephitis and Spilogale. The results confirm Mydaus as a member of the mephitids and the mitogenome will be useful for evolutionary analysis and conservation of the species.

Mitogenomic Architecture of Atlantic Emperor Lethrinus atlanticus (Actinopterygii: Spariformes): Insights into the Lineage Diversification in Atlantic Ocean.

The evolutionary history of emperors, particularly in the Atlantic and Indo-West Pacific Oceans, remains largely unmapped. This study explores the maternal lineage evolution of Lethrinids by examining the complete mitogenome of Lethrinus atlanticus, which is endemic to the Eastern Atlantic Ocean. Utilizing advanced next-generation sequencing, we found that the mitogenome spans 16,789 base pairs and encompasses 37 genes, including 13 protein-coding genes (PCGs), two ribosomal RNAs, 22 transfer RNAs, and an AT-rich control region (CR). Our analysis indicates a preference for AT base pairs in the L. atlanticus mitogenome (53.10%). Most PCGs begin with the ATG codon, except for COI, which starts with GTG. Relative synonymous codon usage reveals high frequencies for alanine, leucine, proline, serine, and threonine. The ratio of nonsynonymous to synonymous substitutions suggests strong negative selection across all PCGs in Lethrinus species. Most transfer RNAs exhibit typical cloverleaf structures, with the exception of tRNA-serine (GCT), which lacks a dihydrouracil stem. Comparative analysis of conserved sequence blocks across the CRs of three Lethrinus species shows notable differences in length and nucleotide composition. Phylogenetic analysis using concatenated PCGs clearly distinguishes all Lethrinus species, including L. atlanticus, and sheds light on the evolutionary relationships among Spariformes species. The estimated divergence time of approximately 20.67 million years between L. atlanticus and its Indo-West Pacific relatives provides insights into their historical separation and colonization during the late Oligocene. The distribution of Lethrinids may be influenced by ocean currents and ecological factors, potentially leading to their speciation across the Eastern Atlantic and Indo-West Pacific. This study enhances our understanding of the genetic diversity and phylogenetic relationships within Lethrinus species. Further exploration of other emperor fish mitogenomes and comprehensive genomic data could provide vital insights into their genetic makeup, evolutionary history, and environmental adaptability in marine ecosystems globally.