Comparative Analysis and Phylogenetic Study of Dawkinsia filamentosa and Pethia nigrofasciata Mitochondrial Genomes.

Smiliogastrinae are recognized for their high nutritional and ornamental value. In this study, we employed high-throughput sequencing technology to acquire the complete mitochondrial genome sequences of Dawkinsia filamentosa and Pethia nigrofasciata. The gene composition and arrangement order in these species were similar to those of typical vertebrates, comprising 13 protein-coding genes, 22 tRNA genes, 2 rRNA genes, and 1 non-coding region. The mitochondrial genomes of D. filamentosa and P. nigrofasciata measure 16,598 and 16,948 bp, respectively. Both D. filamentosa and P. nigrofasciata exhibit a significant preference for AT bases and an anti-G bias. Notably, the AT and GC skew values of the ND6 gene fluctuated markedly, suggesting that the selection and mutation pressures on this gene may differ from those affecting other genes. Phylogenetic analysis, based on the complete mitochondrial genomes of 23 Cyprinidae fishes, revealed that D. filamentosa is closely related to the sister group comprising Dawkinsia denisonii and Sahyadria chalakkudiensis. Similarly, P. nigrofasciata forms a sister group with Pethia ticto and Pethia stoliczkana.

Genetic diversity of wild wintering red-crowned crane (Grus japonensis) by microsatellite markers and mitochondrial Cyt B gene sequence in the Yancheng reserve.

The red-crowned crane (Grus japonensis) is one of the most endangered cranes in the world, and its wild population is still declining. To characterize the genetic resources of East Asian migratory populations, we studied the genetic variation in wild red-crowned cranes at the Yancheng reserve. Based on a partial Cyt b gene sequence, 32 wild red-crowned crane samples were screened from 100 feathers with unknown sample information. Twelve haplotypes were detected using 32 wild red-crowned crane samples. Six pairs of published microsatellite primers were selected for genotyping. A total of 47 alleles were obtained, with an average of 7.8 alleles per locus. All microsatellite loci were highly polymorphic; the average polymorphic information content and expected heterozygosity were 0.721 ± 0.080 and 0.768 ± 0.071, respectively. These results show that the East Asian migratory population of wild red-crowned cranes exhibits high polymorphism. These data are useful for informing reintroduction efforts. The study results provide a basis for understanding the population genetic properties of an endangered crane.

Dispersal of remnant endangered trees in a fragmented and disturbed forest by frugivorous birds.

Most endangered plant species in a fragmented forest behave as a unique source population, with a high dependence on frugivorous birds for recruitment and persistence. In this study, we combined field data of dispersal behavior of birds and GIS information of patch attributes to estimate how frugivorous birds could affect the effective dispersal pattern of Chinese yew (Taxus chinensis) in a fragmented and disturbed forest. Nine bird species were observed to visit T. chinensis trees, with Urocissa erythrorhyncha, Zoothera dauma and Picus canus being the most common dispersers. After foraging, six disperser species exhibited different perching patterns. Three specialist species, P. canus, Turdus hortulorum, and Z. dauma stayed in the source patch, while three generalist species, U. erythrorhyncha, Hypsipetes mcclellandii, and H. castanonotus, could perch in bamboo patches and varied in movement ability due to body size. As a consequence of perching, dispersers significantly contributed to the seed bank, but indirectly affected seedling recruitment. Moreover, the recruitment of T. chinensis was also affected by patch attributes in a fragmented forest (distances to source patch, patch type, size). Our results highlighted the ability of unique source population regeneration of T. chinensis in a fragmented forest, with high dependence on both frugivorous birds and patch attributes, which should be considered in future planning for forest management and conservation.

Comparison and phylogenetic analysis of the mitochondrial genomes of Synodontis eupterus and Synodontis polli.

We aimed to distinguish Synodontis eupterus and Synodontis polli. We performed sequencing and bioinformatic analysis of their mitochondrial genomes and constructed a phylogenetic tree of Mochokidae fish using maximum likelihood and Bayesian methods based on protein-coding gene (PCG) sequences of 14 Mochokidae species. The total length of the S. eupterus mitochondrial genome was 16,579 bp, including 13 (PCGs), 22 tRNA genes, two rRNA genes, and one D-loop, with an AT-biased nucleotide composition (56.0%). The total length of the S. polli mitochondrial genome was 16,544 bp, including 13 PCGs, 22 tRNA genes, two rRNA genes, and one D-loop, with an AT-biased nucleotide composition (55.0%). In both species, except for COI, PCGs use ATG as the starting codon, the vast majority use TAG or TAA as the ending codon, and a few use incomplete codons (T - or TA -) as the ending codon. Phylogenetic analysis showed that S. eupterus and Synodontis clarias converged into one branch, S. polli and Synodontis petricola converged into one branch, Mochokiella paynei, Mochokus brevis, and nine species of the genus Synodontis converged into one branch, and M. paynei clustered with the genus Synodontis. This study lays a foundation for rebuilding a clearer Mochokidae fish classification system.

Sequencing and Analysis of the Complete Mitochondrial Genome of Lentipes ikeae.

We sequenced and analyzed the complete mitochondrial genome of Lentipes ikeae and explored the phylogenetic relationships among Sicydiinae based on mitochondrial genome sequences. The complete mitochondrial genome sequence of L. ikeae was determined using the Illumina HiSeq X Ten sequencing platform, and the gene structural characteristics and base composition were analyzed. Based on the mitochondrial genome sequences of 28 Sicydiinae species published in GenBank and mitochondrial protein-coding genes (PCGs), Acanthogobius flavimanus (Gobionellinae) was selected as an outgroup to construct phylogenetic trees of Sicydiinae using the maximum likelihood and Bayesian inference methods. The mitochondrial genome of L. ikeae (GenBank number: OP764680) has a total length of 16,498 bp and encodes 13 PCGs, 22 transfer RNA genes, two ribosomal RNA genes, and a D-loop (control) region. Gene rearrangement is not observed. The mitochondrial genome of L. ikeae exhibits an AT preference, with AT skew > 0 and GC skew < 0 across the entire genome. The phylogenetic relationships of Sicydiinae based on 13 mitochondrial PCG sequences are Sicydium + (Stiphodon + (Sicyopus + Lentipes)) + Sicyopterus, indicating that Sicydium, Sicyopterus, Lentipes, and Stiphodon are all monophyletic groups.

An Isolated and Deeply Divergent Hynobius Species from Fujian, China.

It is important to describe lineages before they go extinct, as we can only protect what we know. This is especially important in the case of microendemic species likely to be relict populations, such as Hynobius salamanders in southern China. Here, we unexpectedly sampled Hynobius individuals in Fujian province, China, and then worked on determining their taxonomic status. We describe Hynobius bambusicolus sp. nov. based on molecular and morphological data. The lineage is deeply divergent and clusters with the other southern Chinese Hynobius species based on the concatenated mtDNA gene fragments (>1500 bp), being the sister group to H. amjiensis based on the COI gene fragment, despite their geographic distance. In terms of morphology, the species can be identified through discrete characters enabling identification in the field by eye, an unusual convenience in Hynobius species. In addition, we noted some interesting life history traits in the species, such as vocalization and cannibalism. The species is likely to be incredibly rare, over a massively restricted distribution, fitting the definition of Critically Endangered following several lines of criteria and categories of the IUCN Red List of Threatened Species.

Comparative analysis of the mitogenomes of two Corydoras (Siluriformes, Loricarioidei) with nine known Corydoras, and a phylogenetic analysis of Loricarioidei.

Corydoras is a speciose catfish genus from South America with widely investigated phylogenetic and evolutionary relationships. The complete mitogenomes of C.aeneus and C.paleatus were sequenced, assembled, and annotated using next-generation sequencing. The genome arrangements, gene contents, genome structures, base compositions, evolutionary features, codon usage, and tRNA structures of the two mitogenomes were compared and analyzed with nine published mitogenomes of Corydoras. Phylogenetic analysis was performed using concatenated nucleotide sequences with 13 protein-coding genes and two rRNAs with 44 mitogenomes of Siluriformes. These results provide information on the mitogenomes of eleven Corydoras species and evolutionary relationships within the suborder Loricarioidei, which may be applicable for further phylogenetic and taxonomic studies on Siluriformes and Loricarioidei.

Annual Long-Distance Migration Strategies and Home Range of Chinese Sparrowhawk (Accipiter soloensis) from South China.

From 2018 to 2019, two Chinese Sparrowhawks (Bird 01, male; Bird 02, female), Accipiter soloensis, were captured and fitted with Global Positioning System (GPS) loggers in order to identify summering and wintering sites, migration routes, and stop-over sites. The Chinese Sparrowhawks were first fitted with backpack solar GPS satellite trackers in China in order to explore their migration routes. The two Chinese Sparrowhawks successfully completed their migration from southern China, through Nanning city of Guangxi province, China, to Vietnam, Laos, Myanmar, Thailand, Malaysia, and Singapore and finally arriving in Indonesia, where they stayed until the March of the following year. They then returned to China along the original route, arriving in Changsha city, Hunan province, China. The two individuals traveled more than 4000-5000 km. For the first time, telemetry data demonstrate, the linkages between their Indonesia wintering sites, their stop-over sites in Southeast Asia, and their breeding/summering sites near south Yangtze River in the south-central part of China. During this long-distance migration, 2653 bird satellite sites were received. The autumn migration durations for the two Chinese Sparrowhawks were 84 days and 50 days, respectively, compared to 83 days and 49 days in spring. The median stop-over duration was 12.7 and 9.3 days, respectively and the median speed of travel was 74.2 km/day during the autumn migration and 73.9 km/day during the spring migration. Furthermore, two and one stop-over sites and one and three stop-over sites were used during the autumn and spring migrations of Chinese Sparrowhawks 01 and 02, respectively. The Chinese Sparrowhawks migrated long distances and used stop-over sites during their migration. Based on the home range analysis, we can conclude that Chinese Sparrowhawks reach their maximum home range in the summer and have multiple nuclear domains.

Spatial patterns in the size of Chinese lizards are driven by multiple factors.

BACKGROUND: For almost two centuries, ecologists have examined geographical patterns in the evolution of body size and the associated determinants. During that time, one of the most common patterns to have emerged is the increase in body size with increasing latitude (referred to as Bergmann's rule). Typically, this pattern is explained in terms of an evolutionary response that serves to minimize heat loss in colder climates, mostly in endotherms. In contrast, however, this rule rarely explains geographical patterns in the evolution of body size among ectotherms (e.g., reptiles). LOCATION: China. AIM: In this study, we assembled a dataset comprising the maximum sizes of 211 lizard species in China and examined the geographical patterns in body size evolution and its determinants. Specifically, we assessed the relationship between body size and climate among all lizard species and within four major groups at both assemblage and interspecific levels. RESULTS: Although we found that the body size of Chinese lizards was larger in warmer regions, we established that at the assemblage level, size was correlated with multiple climatic factors, and that body size-climate correlations differed within the four major groups. Phylogenetic analysis at the species level revealed that no single climatic factor was associated with body size, with the exception of agamids, for which size was found to be positively correlated with temperature. MAIN CONCLUSIONS: Geographical patterns in Chinese lizard body size are driven by multiple factors, and overall patterns are probably influenced by those of the major groups. We suggest that our analyses at two different levels may have contributed to the inconsistent results obtained in this study. Further studies investigating the effects of altitude and ecological factors are needed to gain a more comprehensive understanding of the evolution of ectotherm body size.

Cones structure and seed traits of four species of large-seeded pines: Adaptation to animal-mediated dispersal.

Seed dispersal selection pressures may cause morphological differences in cone structure and seed traits of large-seeded pine trees. We investigated the cone, seed, and scale traits of four species of animal-dispersed pine trees to explore the adaptations of morphological structures to different dispersers. The four focal pines analyzed in this study were Chinese white pine (Pinus armandi), Korean pine (P. koraiensis), Siberian dwarf pine (P. pumila), and Dabieshan white pine (P. dabeshanensis). There are significant differences in the traits of the cones and seeds of these four animal-dispersed pines. The scales of Korean pine and Siberian dwarf pine are somewhat opened after cone maturity, the seeds are closely combined with scales, and the seed coat and scales are thick. The cones of Chinese white pine and Dabieshan white pine are open after ripening, the seeds fall easily from the cones, and the seed coat and seed scales are relatively thin. The results showed that the cone structure of Chinese white pine is similar to that of Dabieshan white pine, whereas Korean pine and Siberian dwarf pine are significantly different from the other two pines and vary significantly from each other. This suggests that species with similar seed dispersal strategies exhibit similar morphological adaptions. Accordingly, we predicted three possible seed dispersal paradigms for animal-dispersed pines: the first, as represented by Chinese white pine and Dabieshan white pine, relies upon small forest rodents for seed dispersal; the second, represented by Korean pine, relies primarily on birds and squirrels to disperse the seeds; and the third, represented by Siberian dwarf pine, relies primarily on birds for seed dispersal. Our study highlights the significance of animal seed dispersal in shaping cone morphology, and our predictions provide a theoretical framework for research investigating the coevolution of large-seeded pines and their seed dispersers.

Five new mitogenomes of Phylloscopus (Passeriformes, Phylloscopidae): Sequence, structure, and phylogenetic analyses.

The genus Phylloscopus belongs to the order Passeriformes and subfamily Phylloscopinae within the family Sylviidae. Phylloscopus, a small insectivore widely distributed in the old world, includes 66 species and 112 subspecies. We identified five new Phylloscopus mitogenomes: P. tenellipes (16,904 base pairs (bp), MK390475), P. coronatus (16,905 bp, MK533705), P. borealis (16,881 bp, MK390476), P. schwarzi (16,920 bp, MK411584), and P. borealoides (16,904 bp, MN125373). All contained 37 genes, including 13 protein-coding genes, two rRNA genes, 22 tRNA genes, and two control regions. Seven Phylloscopus species were compared to the five new mitogenomes and the published complete P. inornatus and P. proregulus mitochondrial sequences. The genetic distance of 13 single protein-coding genes exhibited low variation within all seven Phylloscopus mitogenomes. Based on the Ka/Ks ratios, the molecular evolution patterns of single protein-coding genes were relatively consistent among Phylloscopus bird species. Phylogenetic analysis verified that subspecies of the Pale-legged Leaf Warbler P. tenellipes borealoides could be promoted to the Sakhalin Leaf Warbler P. borealoides. Gene order and genome organization information is useful to understand evolutionary relationships among Phylloscopus species. The complete mitogenomes of these five Phylloscopus species provide genetic markers for species identification, population genetics, and phylogeographic studies of birds.

Mitogenome of the little owl Athene noctua and phylogenetic analysis of Strigidae.

New advances in molecular approaches for DNA analysis have enhanced our understanding of the phylogenetic relationship of birds. The Little Owl (Athene noctua) is of great significance for the integrated management of forest diseases and control of regional pests. Here, we sequenced and annotated the 17,772 bp complete mitogenome of A. noctua. The mitogenome encoded 37 typical mitochondrial genes: 13 protein-coding genes, two ribosomal RNA genes, 22 transfer RNA, and one non-coding control region (D-loop). The organization and location of genes in the A. noctua mitogenome were consistent with those reported for other Strigidae birds. Phylogenetic relationships based on Bayesian inference and Maximum likelihood methods showed that A. noctua has close relationships with Athene brama and Glaucidium cuculoides, confirming that A. noctua belongs to the Strigidae family. The phylogenetic relationships among seven genera of the Strigidae family used in this study were: Ninox and the other six genera were far apart, Otus and the clade ((Bubo + Strix) + Asio) were clustered into one branch, and Athene and Glaucidium were clustered into one branch. This phylogenetic classification is consistent with prior taxonomic studies on the Strigidae family. Our results provide new mitogenomic data to support further phylogenetic and taxonomic studies of Strigidae.

Complete mitochondrial genome of the Ruff, Calidris pugnax (Aves, Scolopacidae).

This paper reports the mitochondrial genome of Calidris pugnax, which is a closed circular molecule of 16,902 bp. The overall base composition of this species is 25.2% T, 30.6% C, 32.0% A, and 12.2% G, with an A + T content of 55.2%. The structure of the mitogenome is a typical vertebrate mitochondrial gene arrangement. Phylogenetic analysis of complete mitochondrial genome concatenated sequences from 13 species from 6 genera was conducted using the maximum-likelihood (ML) model. The topology demonstrated that the mitogenome of this species was genetically closest to that of Calidris tenuirostris. Calidris pugnax mitogenome can contribute to our understanding of the phylogeny and evolution of this species.

Comparative analysis of the gut microbiota of hornbill and toucan in captivity.

Gut microbiota plays an important role in animals and are considered microbial organs. Hornbill and toucan are birds of the same ecotypes with high appreciative value. In this study, we characterized and compared the gut microbiota of toco toucan (Ramphastos toco), great hornbill (Buceros bicornis) and wreathed hornbill (Rhyticeros undulatus) using 16S rRNA high-throughput sequencing technology, and further discussed the influence of host bird genetics on its gut microbiota. We identified 10,847 operational taxonomic units (OTUs) from the hyper-variable V4-V5 region, representing 14 phyla that were dominated by the Firmicutes, Proteobacteria, Cyanobacteria, Fusobacteria, Actinobacteria, and Bacteroidetes. Alpha diversity indices showed no significant difference among the three species (p > 0.1). However, great hornbill and toco toucan shared a high number of OTUs. Principal component analysis also revealed highly similar gut microbiotas between the two distant species. Therefore, environmental factors might dominate over host genetics in shaping the gut microbiotas of hornbill and toucan. Our study would contribute in elucidating adaptation of the hornbill and toucan to environmental change.

The complete mitochondrial genome of Asian brown flycatcher Muscicapa latirostris (Passeriformes: Muscicapidae).

We report the mitochondrial genome of Muscicapa latirostris. The overall base composition of the Asian brown flycatcher mitogenome is 24.31% T, 31.62% C, 29.62% A, and 14.44% G, with an A + T content of 53.93%. The total length of the sequence is 18,026 bp (13 protein-coding genes, 22 transfer RNA genes, 2 ribosomal RNA genes, and 2 control regions). Phylogenetic analysis was performed based on the concatenated nucleotide sequences of cytochrome c oxidase subunit I and cytochrome b using the neighbor-joining method and the Kimura 2-parameter model in MEGA 7.0 with 1000 bootstrap replicates.

Analysis of the Gut Microbiome of Wild and Captive Père David's Deer.

Père David's deer (Elaphurus davidianus or milu) is a highly endangered species originating from China, and many deer are currently being raised in captivity for gradual re-introduction to the wild. Wild and captive deer currently live in the same region but have vastly different diets. In this study, we used 16S rRNA high-throughput sequencing to identify the healthy core microbiome in the gut of wild and captive Père David's deer and investigate how dietary factors influence the gut microbiome by comparing their differences. A core shared gut microbiome was identified in healthy Père David's deer, which was similar to that of other ruminants, mainly comprising the phyla Firmicutes and Bacteroidetes. There were no differences in the richness or diversity of the gut microbiome between the wild and captive deer. However, PCA and ANOSIM demonstrated clear differences in the microbial community structure between the captive and wild deer, which mainly manifested as changes in the relative abundance of 39 bacterial genera. As the majority of these genera were not dominant in the deer gut, no significant difference was detected in functional modules related to the microbiome between the two groups. Therefore, the difference in dietary factors does not appear to affect the healthy core gut microbiome between captive and wild Père David's deer, suggesting strong co-evolution and the possibility of re-establishment in the wild. These data could guide future applications of population management in Père David's deer conservation.

Genetic diversity analysis of Peking gecko (Gekko swinhonis) in mid-Eastern China based on mitochondrial COI and Cyt b gene sequences.

To understand the genetic diversity of Peking gecko (Gekko swinhonis) populations in its endemic region, 60 individuals were sampled from Lushan, Qi, and Linying counties in Henan Province, China. Through PCR amplification and Sanger sequencing, 120 sequences with lengths of 652 bp (COI) and 739 bp (Cyt b) were obtained, and nine haplotypes were detected for each gene. Overall, results indicated that Peking gecko populations in China have high genetic diversity and significant genetic differentiation. This study provides necessary scientific basis for the protection of Peking gecko germplasm resources.

The complete mitochondrial genome of dark-sided flycatcher Muscicapa sibirica (Passeriformes: Muscicapidae).

We report the mitochondrial genome of Muscicapa sibirica. The overall base composition of the dark-sided flycatcher mitogenome is 24% T, 31.8% C, 29.4% A, and 14.8% G, with an A + T content of 53.4%. The total length of the sequence is 17,879 bp (13 protein-coding genes, 22 transfer RNA genes, 2 ribosomal RNA genes, and 2 control regions). Phylogenetic analysis was performed based on the concatenated nucleotide sequences of cytochrome c oxidase subunit I and cytochrome b using the neighbor-joining method and the Kimura 2-parameter model in MEGA 7.0 with 1000 bootstrap replicates.

The complete mitochondrial genome of Zosterops japonicas (Aves, Zosteropidae).

The complete mitochondrial genome (mitogenome) sequence of Zosterops japonicus was determined by shotgun sequencing. The total length of mitogenome is 17 809 bp, and contains 13 protein-coding genes, 22 tRNA genes, 2 ribosome RNA genes and 2 control regions (CR). All the protein-coding genes in Z. japonicus were distributed on the H-strand, except for the ND6 subunit gene and eight tRNA genes which were encoded on the L-strand. The phylogenetic tree of Z. japonicus and 13 other species belonging to order Passeriformes was built. The DNA data presented here will be useful to study the evolutionary relationships and genetic diversity of Z. japonicus.

Complete mitochondrial genome of oriental magpie-robin Copsychus saularis (Aves: Muscicapidae).

The total length of mitogenome of Copsychus saularis is 16 827 bp and contains 13 protein-coding genes, 22 tRNA genes, two rRNA genes and one D-loop. The phylogenetic tree of C. saularis and 13 other species belonging to Passeriformes was built.