Complete Mitochondrial Genome and Phylogenetic Analysis of Tarsiger indicus (Aves: Passeriformes: Muscicapidae).

Tarsiger indicus (Vieillot, 1817), the White-browed Bush Robin, is a small passerine bird widely distributed in Asian countries. Here, we successfully sequenced its mitogenome using the Illumina Novaseq 6000 platform (Illumina, San Diego, CA, USA) for PE 2 × 150 bp sequencing. Combined with other published mitogenomes, we conducted the first comprehensive comparative mitogenome analysis of Muscicapidae birds and reconstructed the phylogenetic relationships between Muscicapidae and related groups. The T. indicus mitogenome was 16,723 bp in size, and it possessed the typical avian mitogenome structure and organization. Most PCGs of T. indicus were initiated strictly with the typical start codon ATG, while COX1 and ND2 were started with GTG. RSCU statistics showed that CUA, CGA, and GCC were relatively high frequency in the T. indicus mitogenome. T. cyanurus and T. indicus shared very similar mitogenomic features. All 13 PCGs of Muscicapidae mitogenomes had experienced purifying selection. Specifically, ATP8 had the highest rate of evolution (0.13296), whereas COX1 had the lowest (0.01373). The monophylies of Muscicapidae, Turdidae, and Paradoxornithidae were strongly supported. The clade of ((Muscicapidae + Turdidae) + Sturnidae) in Passeriformes was supported by both Bayesian Inference and Maximum likelihood analyses. The latest taxonomic status of many passerine birds with complex taxonomic histories were also supported. For example, Monticola gularis, T. indicus, and T. cyanurus were allocated to Turdidae in other literature; our phylogenetic topologies clearly supported their membership in Muscicapidae; Paradoxornis heudei, Suthora webbiana, S. nipalensis, and S. fulvifrons were formerly classified into Muscicapidae; we supported their membership in Paradoxornithidae; Culicicapa ceylonensis was originally classified as a member of Muscicapidae; our results are consistent with a position in Stenostiridae. Our study enriches the genetic data of T. indicus and provides new insights into the molecular phylogeny and evolution of passerine birds.

Complete Mitogenomes of Ticks Ixodes acutitarsus and Ixodes ovatus Parasitizing Giant Panda: Deep Insights into the Comparative Mitogenomic and Phylogenetic Relationship of Ixodidae Species.

Ticks rank second in the world as vectors of disease. Tick infestation is one of the factors threatening the health and survival of giant pandas. Here, we describe the mitogenomes of Ixodes acutitarsus and Ixodes ovatus parasitizing giant pandas, and perform comparative and phylogenetic genomic analyses on the newly sequenced and other available mitogenomes of hard ticks. All six newly determined mitogenomes contain a typical gene component and share an ancient Arthropoda gene arrangement pattern. Our study suggests that I. ovatus is a species complex with high genetic divergence, indicating that different clades of I. ovatus represent distinct species. Comparative mitogenomic analyses show that the average A + T content of Ixodidae mitogenomes is 78.08%, their GC-skews are strongly negative, while AT-skews fluctuate around 0. A large number of microsatellites are detected in Ixodidae mitogenomes, and the main microsatellite motifs are mononucleotide A and trinucleotide AAT. We summarize five gene arrangement types, and identify the trnY-COX1-trnS1-COX2-trnK-ATP8-ATP6-COX3-trnG fragment is the most conserved region, whereas the region near the control region is the rearrangement hotspot in Ixodidae mitogenomes. The phylogenetic trees based on 15 genes provide a very convincing relationship (Ixodes + (Robertsicus + ((Bothriocroton + Haemaphysalis) + (Amblyomma + (Dermacentor + (Rhipicentor + (Hyalomma + Rhipicephalus))))))) with very strong supports. Remarkably, Archaeocroton sphenodonti is embedded in the Haemaphysalis clade with strong supports, resulting in paraphyly of the Haemaphysalis genus, so in-depth morphological and molecular studies are essential to determine the taxonomic status of A. sphenodonti and its closely related species. Our results provide new insights into the molecular phylogeny and evolution of hard ticks, as well as basic data for population genetics assessment and efficient surveillance and control for the giant panda-infesting ticks.

Characterization of the complete mitochondrial genome of Otus lettia: exploring the mitochondrial evolution and phylogeny of owls (Strigiformes).

Large-scale molecular phylogenetic studies of the avian order Strigiformes have been performed, and numerous mitochondrial genomes have been determined. However, their intergeneric relationships are still controversial, and few comprehensive comparative analyses of mitochondrial genomes have been conducted on Strigiformes. In this study, the mitochondrial genome of Otus lettia was determined and compared with other Strigiformes. The O. lettia mitochondrial genome was 16,951 bp in size. For Strigiformes, atp8 can be used as a suitable molecular marker for population genetic diversity, while cox1 is a candidate barcoding marker for species identification. All protein-coding genes may be under strong purifying selection pressure, and one extra cytosine insertion located in nad3 is common to all owls except Tyto longimembris, T. alba, and Athene noctua. Four different mitochondrial gene arrangement types were found among the Strigiformes mitogenomes, and their evolutionary relationship between each other can be perfectly explained by the tandem duplication and random loss model. The phylogenetic topologies using the mitochondrial genomes showed that target species O. lettia had a closer relationship with O. scops + O. sunia than O. bakkamoena, the genus Glaucidium was paraphyletic, and the Ninox clade was located at the basal position of Strigidae lineage. Our phylogenetic trees also supported the previous recommendations that Sceloglaux albifacies, Ciccaba nigrolineata, and Ketupa flavipes should be transferred to Ninox, Strix, and Bubo, respectively. These findings will be helpful in further unraveling the mitochondrial evolution and phylogeny of Strigiformes.

Viral metagenomics revealed diverse CRESS-DNA virus genomes in faeces of forest musk deer.

BACKGROUND: Musk deer can produce musk which has high medicinal value and is closely related to human health. Viruses in forest musk deer both threaten the health of forest musk deer and human beings. METHODS: Using viral metagenomics we investigated the virome in 85 faeces samples collected from forest musk deer. RESULTS: In this article, eight novel CRESS-DNA viruses were characterized, whole genomes were 2148 nt-3852 nt in length. Phylogenetic analysis indicated that some viral genomes were part of four different groups of CRESS-DNA virus belonging in the unclassified CRESS-DNA virus, Smacoviridae, pCPa-like virus and pPAPh2-like virus. UJSL001 (MN621482), UJSL003 (MN621469) and UJSL017 (MN621476) fall into the branch of unclassified CRESS-DNA virus (CRESSV1-2), UJSL002 (MN621468), UJSL004 (MN621481) and UJSL007 (MN621470) belong to the cluster of Smacoviridae, UJSL005 (MN604398) showing close relationship with pCPa-like (pCRESS4-8) clusters and UJSL006 (MN621480) clustered into the branch of pPAPh2-like (pCRESS9) virus, respectively. CONCLUSION: The virome in faeces samples of forest musk deer from Chengdu, Sichuan province, China was revealed, which further characterized the diversity of viruses in forest musk deer intestinal tract.

Viral metagenomics reveals significant viruses in the genital tract of apparently healthy dairy cows.

The virome in genital tract secretion samples collected from 80 dairy cattle in Shanghai, China, was characterized. Viruses detected included members of the families Papillomaviridae, Polyomaviridae, Hepeviridae, Parvoviridae, Astroviridae, Picornaviridae, and Picobirnaviridae. A member of a new species within the genus Dyoxipapillomavirus and six circular Rep-encoding single-stranded DNA (ssDNA) (CRESS-DNA) viral genomes were fully sequenced and phylogenetically analyzed. The prevalence of bovine polyomaviruses 1 and 2 was measured by PCR to be 10% (8/80) and 6.25% (5/80), respectively. PCR screening also indicated that the novel papillomavirus ujs-21015 and bovine herpesvirus 6 were present in three and two out of the 80 samples, respectively.

Morphology and morphogenesis of Epistylis plicatilis ehrenberg, 1831 (Ciliophora, Peritrichia) from Wuhan, China.

A limnetic peritrichous ciliate, Epistylis plicatilis Ehrenberg, 1831, was collected from a freshwater ditch beside Moshan Hill, Wuhan, China. Its morphology, infraciliature, and morphogenesis were investigated based on specimens examined in vivo, following staining with protargol and by scanning electron microscopy. The characteristics of the Wuhan population of E. plicatilis are as follows: 1) colonial, each colony typically comprising 30-50 individuals, with a dichotomously branched, noncontractile stalk; 2) fully expanded zooids measure 90-155 × 30-50 µm in vivo; 3) a series of 6 or 7 conspicuous folds appear in the posterior region of the zooid when it contracts; 4) single horseshoe-shaped macronucleus oriented transversely; 5) single contractile vacuole located in peristomial region on dorsal wall of infundibulum; 6) myoneme system comprises 20-24 longitudinal fibers, peristomial disk fibers as a wreath-like net and peristomial ring fibers; 7) narrowly spaced transverse striations on the surface of the body; 8) infundibular polykineties 1 and 2 are three-rowed, infundibular polykinety 3 is two-rowed; and 9) stomatogenesis is of the buccokinetal type; in the new oral apparatus, infundibular polykineties 2 and 3, the haplokinety, and the germinal kinety all originate from the germinal kinety of the parental oral apparatus whereas the polykinety and infundibular polykinety 1 originate from the parental haplokinety. An improved diagnosis of E. plicatilis is supplied.