Complete mitochondrial genome of spined sleeper Eleotris oxycephala (Perciformes,Eleotridae) and phylogenetic consideration

The complete mitochondrial genome of Eleotris oxycephala was determined to be 16,527 bp in length with (A + T) content of 53%, and it consists of 13 protein-coding genes, 22 tRNAs, 2 ribosomal RNAs, and a control region. The gene composition and the structural arrangement of the E. oxycephala complete mtDNA were identical to most of other vertebrates. Phylogenetic analysis based on different sequences of species of the Gobioidei suborder and different methods showed that E. oxycephala formed a cluster with Eleotris acanthopoma and Eleotridae were divided into two clades. Furthermore, extensive taxon sampling and more molecular information are needed to confirm the phylogenetic relationships among the Gobioidei.     

Complete mitochondrial genome of the Himalayan serow (Capricornis thar) and its phylogenetic status within the genus Capricornis

The genus Capricornis (Caprinae, Bovidae) includes six species, i.e., Capriconis sumatraensis, Capricornis swinhoei, Capricornis crispus, Capricornis rubidus, Capricornis milneedwardsii and Capricornis thar. Based on morphological, anatomical and physiological evidence, the Himalayan serow (C. thar), which is distributed in the mountain regions of the Tibetan Plateau and adjacent areas, is generally classified as a species of the genus Capricornis. However, considering the lack of molecular phylogenetic evidence, a heated controversy still exists over the taxonomic position of the Himalayan serow. To determine the phylogenetic status of C. thar, we sequenced the complete mitochondrial genome (mtDNA) of one Himalayan serow using the polymerase chain reaction (PCR) technique. Then, we constructed a molecular phylogenetic tree of the genus Capricornis and its related species in the Caprinae subfamily based on maximum likelihood and Bayesian interference methods. The results reflect that the structural characteristics, nucleotide content and codon usage bias of the mitochondrial genome of the Himalayan serow were similar to those of other serows. A phylogenetic analysis using two rRNA genes and 12 encoded protein-coding genes indicated that C. thar is clustered within the C. milneedwardsii clade, which is a sister group of C. sumatraensis. The present study provides useful information about the evolution of the Himalayan serow, which will be essential for conservation genetic studies.     

The complete mitochondrial genome of Diaphorina citri (Hemiptera: Psyllidae) and phylogenetic analysis

The Asian citrus psyllid, Diaphorina citri Kuwayama (Hemiptera: Psyllidae) is the most serious pest of citrus as the vector of Huanglongbing (HLB), the citrus greening disease. In this study, the complete mitochondrial genome (mitogenome) of D. citri has been sequenced and annotated, and a comparative analysis is provided with known Psylloidea species. The mitogenome of D. citri is a typical circular molecular of 15,038 bp in length with an A + T content of 74.56%, contains the typical 37 genes and the gene order is identical to the other Psylloidea mitogenomes. The nucleotide composition and codon usage of D. citri are similar to the four Psylloidea species. All protein-coding genes (PCGs) use standard initiation codons (TAN), stop with TAA and TAG except ND2 and ND5 which stop with incomplete termination codon T. All tRNAs have the typical clover-leaf structure, with the exception of trnS1 lacking the dihydrouridine (DHU) arm. The control region is located between rrnL and the trnI gene with the highest A + T content among the five Psylloidea species. Phylogenetic analysis is conducted based on the 13 PCGs or/and 2 rRNAs of 23 Sternorrhycha mitogenomes. Both maximum likelihood (ML) and Bayesian inference (BI) analysis suggest a clear relationship of Psylloidea, Aleyrodoidea and Aphidoidea within Sternorrhycha, which support the traditional morphological classification.     

The complete mitochondrial genome of Eriocheir japonica sinensis (Decapoda: Varunidae) and its phylogenetic analysis

The complete mitochondrial genome (mitogenome) can provide novel insights into understanding the mechanisms underlying mitogenome evolution. In this study, the complete mitogenome of Eriocheir japonica sinensis (Decapoda: Varunidae) was determined to be 16,378 bp, including 13 protein-coding genes (PCGs), two rRNA genes, 22 tRNA genes and a D-loop region. The AT skew of the E. j. sinensis mitogenome was slightly negative (−0.016), indicating a higher number of T compared with A nucleotides. The nucleotide composition of the mitogenome was also biased toward A + T nucleotides (71.6%). All PCGs were initiated by ATN codons. Eight of the 13 PCGs harbored the incomplete termination codon by T, or TA. All other tRNA genes displayed a typical clover-leaf structure of mitochondrial tRNA. The D-loop region of the E. j. sinensis mitogenome was 918 bp in length. Based on 13 PCGs, phylogenetic analysis confirmed the placement of E. j. sinensis within the Varunidae.     

Complete mitochondrial genome of Periplaneta brunnea (Blattodea: Blattidae) and phylogenetic analyses within Blattodea

The complete mitochondrial genome (mitogenome) of Periplaneta brunnea was sequenced in this study and used to reconstruct the phylogenetic relationship of Blattodea. The circular mitogenome was 15,604?bp long and exhibited typical gene organization and order, consistent with other sequenced Periplaneta mitogenomes. The initiation codon of the P. brunnea COX1 gene was unusual in that no typical ATN or TTG start codon was found. The two longest intergenic spacer sequences found in the P. brunnea mitogenome were 21 and 17?bp long. Twenty-one base spacer had a 4?bp motif (TATT) between tRNA-Glu and tRNA-Met that conservatively displayed in 9 sequenced blattarian mitogenomes. The second spacer was between tRNA-Ser (UCN) and NAD1 containing a 7?bp motif (WACTTAA) that was highly conserved in 14 blattarian mitogenomes. The control region showed a relatively fixed motif present in 6 Blattidae mitogenomes, with a big stem-loop structure. Phylogenetic analyses were conducted using site-homogeneous models based on 13 protein-coding genes (PCGs) and two RNA genes. The trees derived from Bayesian inference and maximum likelihood analyses and recovered a relatively stable relationship among major lineages except for the position of Polyphagidae and inter-family relationships of Blaberidae. Analyses supported the monophyly of Blattidae, Blaberidae, Blattellidae, Polyphagidae, Dictyoptera, and the paraphyly of Blattaria. We also found Mantodea was the sister clade to (Blattaria?+?Isoptera), being the basal position of Dictyoptera in all topologies. Meanwhile, our results also consistently supported that Isoptera should be clustered with Blattaria of Blattodea.     

The mitochondrial genome of Gatzara jezoensis (Neuroptera: Myrmeleontidae) and phylogenetic analysis of Neuroptera

Phylogenetic relationship within Neuroptera is controversial, particularly for the various hypotheses based on both morphological and molecular evidence. In the present study, we determined the complete mitochondrial genome (mitogenome) of Gatzara jezoensis, which is the second representative of the tribe Dendroleontini. The G. jezoensis mitogenome contained the conserved set of 37 mitochondrial genes and a putative control region, with a conserved gene arrangement which was similar to that of most sequenced neuropteran mitogenomes. All transfer RNAs exhibited the canonical cloverleaf secondary structure, except for trnS^(AGN). The control region contained two conserved elements (ploy-T stretch and ATGGTTCAAYAAAATAAYYCYCTC motif) and abundant microsatellite-like elements. The phylogenetic analysis of sequenced neuropteran mitogenomes using the concatenated protein-coding genes (PCGs) and ribosomal genes recovered the monophyly of Myrmeleontidae, which revealed this dataset could generate the more robust phylogeny of Neuroptera than that of 13 PCGs dataset.     

The complete mitochondrial genome of Eterusia aedea (Lepidoptera,Zygaenidae) and comparison with other zygaenid moths

Zygaenidae comprises >1036 species, including many folivorous pests in agriculture. In the present study, the complete mitochondrial genome (mitogenome) of a major pest of tea trees, Eterusia aedea was determined. The 15,196-bp circular genome contained the common set of 37 mitochondrial genes (including 13 protein-coding genes, two rRNA genes, and 22 tRNA genes) and exhibited the similar genomic features to reported Zygaenidae mitogenome. Comparative analyses of Zygaenidae mitogenomes showed a typical evolutionary trend of lepidopteran mitogenomes. In addition, we also investigated the gene order of lepidopteran mitogenomes and proposed that the novel gene order trnA-trnR-trnN-trnE-trnS-trnF from Zygaenidae and Gelechiidae and most other gene rearrangements of this tRNA cluster evolved independently. Finally, the mitogenomic phylogeny of Lepidoptera was reconstructed based on multiple mitochondrial datasets. And all the phylogenetic results revealed the sister relationships of Cossoidea and Zygaenoidea with both BI and ML methods, which is the first stable mitogenomic evidence for this clade.     

Unusual mitochondrial genome structure of the freshwater goby Odontobutis platycephala: rearrangement of tRNAs and an additional non-coding region

Mitochondrial DNA was isolated from the Korean freshwater gobioid fish Odontobutis platycephala by long-polymerase chain reaction with conserved primers and this mtDNA was sequenced by primer walking using flanking sequences as sequencing primers. The resultant O. platycephala mtDNA sequence was found to be 17 588 bp in size with a mostly conserved structural organization when compared with that of other teleost fish. Rearrangements of tRNAs (tRNA-Ser, tRNA-Leu, tRNA-His) and an additional non-coding region (533 bp) were present between the ND4 and ND5 genes. In the present paper, the basic characteristics of the O. platycephala mitochondrial genome is reported, including its structural organization, base composition of rRNAs, tRNAs and protein-encoding genes, characteristics of mitochondrial tRNAs and the peculiar rearrangement features of some parts of the mtDNA. Phylogenetic analysis performed using the cytochrome b gene sequences of 16 Korean freshwater fishes (15 gobioids) with the Bayesian algorithm showed that O. platycephala forms a clade (1·00 of posterior probability) with other species of Odontobutis . This suggests that the observed rearrangement between the ND4 and ND5 genes in the O. platycephala mitogenome reflects independent events.     

Complete mitochondrial genome of Saturnia jonasii (Lepidoptera: Saturniidae): Genomic comparisons and phylogenetic inference among Bombycoidea

The complete mitochondrial genome (mitogenome) of Saturnia jonasii (Lepidoptera: Saturniidae) was sequenced and compared to those of 19 other bombycoid species. Furthermore, the mitogenome sequences were used to infer phylogenetic relationships among bombycoid species. The 15,261-bp Saturnia jonasii mitogenome contained the typical sets of genes and gene arrangements found in majority of Lepidoptera. All Bombycoidea species, including Saturnia jonasii, have a 15–33-bp spacer sequence at the trnS₂-ND1 junction. The phylogenetic reconstruction of bombycoid species consistently and strongly supported monophylies of the families, Saturniidae, Bombycidae, and Sphingidae, based on Bayesian inference (BI) and maximum-likelihood (ML) methods. Among these families, the Bombycidae and Sphingidae species consistently showed a sister relationship, regardless of data partitions; the BI method strongly supported this relationship, whereas it was moderately supported using the ML method.     

Detection of two different mitochondrial genomes in a gall wasp species,Andricus mairei (Hymenoptera: Cynipoidea: Cynipidae)

Mitochondrial genomes (mitogenomes) have been used widely in comparative and evolutionary genomics, molecular evolution, phylogenetics, and population genetics, but very limited information is available for the family Cynipidae. In this report, we described the mitogenome of Andricus mairei. The mitogenome of A. mairei was 16,514 bp in length and contained a typical set of 37 genes. Two control regions (CRs) were detected, one being a partial reverse repeat of the other. In a comparison with the putative ancestral mitogenome, gene rearrangements were found in transfer RNA (tRNA) genes, protein-coding genes and ribosomal RNA (rRNA) genes. Consistent with other Cynipidae species, the gene rearrangement of A. mairei had four obvious characteristics: trnE and trnF had inverted and swapped positions; rrnL and rrnS genes had moved into the cob–nad1 junction; a novel tRNA gene cluster trnL1–trnI–trnL2–trnW–trnM–trnQ had been formed between nad1 and nad2; and trnV had inverted and moved to the nad2–cox1 gene junction. Furthermore, A. mairei had two types of mitochondrial circular DNA molecules. Type II differed from type I in an inverted rearrangement of a large fragment of 3349 nucleotides, including two CRs and two rRNA genes.     

缅甸陆龟线粒体全基因组的测序及分析

本文参照近缘物种的线粒体基因组序列,设计17对特异引物,采用LD-PCR、PCR及测序技术获得了我国广西产缅甸陆龟的线粒体全基因组序列,分析了其基因组特点和各基因的定位。结果表明:缅甸陆龟线粒体基因组全长为16813bp,碱基组成为35.30%A、26.47%T、12.09%G、26.14%C,包括13个蛋白质编码基因、2个rRNA基因、22个tRNA基因和1个非编码基因控制区(D-Loop区)。缅甸陆龟线粒体基因组各基因长度、位置与典型的脊椎动物相似,其编码蛋白质区域和rRNA基因与其它脊椎动物具有很高的同源性,显示龟类线粒体基因组在进化上十分保守。将缅甸陆龟的线粒体基因组序列提交到GenBank,获得的检索号为DQ656607。本文还结合GenBank中已发表的其它16种龟鳖类动物的线粒体基因组序列,探讨龟鳖类动物不同科间的系统进化关系。     

Complete mitochondrial genomes of three sea basses Lateolabrax (Perciformes,Lateolabracidae) species: Genome description and phylogenetic considerations

Genus Lateolabrax consists of three species, Japanese sea bass Lateolabrax japonicus, spotted sea bass Lateolabrax maculatus and blackfin sea bass Lateolabrax latus. The complete mitochondrial DNA (mtDNA) of the three sea basses were amplified and sequenced to characterize and discuss their phylogenetic relationships. The length of mitogenomes was 16,593 bp, 16,479 bp and 16,600 bp, respectively, and all of them consisted of 13 protein-coding genes, 2 ribosomal RNA (rRNA), 22 transfer RNA (tRNA) and a control region, which are typical for mtDNA of vertebrate. Most genes were encoded on the H-strand, except for the ND6 and eight tRNA genes encoding on the L-strand. A significant variation among the three species was detected in length of the control region. Phylogenetic relationship among the three species was constructed based on the datasets, including the 12 protein-coding genes (except ND6 gene), 22 tRNA and 2 rRNA sequences. The results supported the sister taxon between L. japonicus and L. maculatus. The genetic resources reported here are useful for further studies in taxonomy and phylogeny of the three sea basses and related species.     

中国地鼠线粒体基因组的序列分析与分子进化

目的 获得中国地鼠线粒体基因组序列,为线粒体疾病模型提供分子数据.方法 参照近缘物种的线粒体基因组序列,设计27对特异引物,采用TD-PCR及测序技术获得了中国地鼠的线粒体全基因组序列,分析了其基因组特点和各基因的定位.还结合GenBank中已发表的其他5种啮齿类动物的线粒体基因组序列,探讨啮齿类动物不同科间的系统进化关系.结果 中国地鼠线粒体基因组全长为16 283 bp,碱基组成为33.53％A、30.50％T、12.98％G、22.80％C,包括13个蛋白质编码基因、2个rRNA基因、22个tRNA基因和1个非编码基因控制区.中国地鼠和金黄地鼠亲缘关系最近.结论 中国地鼠线粒体基因组各基因长度、位置与典型的啮齿类动物相似,其编码蛋白质区域和rRNA基因与其他啮齿类动物具有很高的同源性,显示线粒体基因组在进化上十分保守.5种动物的分子系统进化树与传统分类地位一致.     

草兔线粒体基因组全序列及其系统发育关系分析

草兔(Lepus capensis)在我国数量多,分布广,但人们对草兔的系统地理学、草兔与其他兔类的系统发育关系了解不多,其亚种水平的分类也长期存在争议。本研究通过LA-PCR 技术对草兔线粒体基因组全序列进行PCR 扩增、序列测定和分析,并基于线粒体基因组12 个蛋白质编码基因10 776 bp的核苷酸序列,采用贝叶斯法(BI)和最大似然法(ML)构建哺乳纲(Mammalia) 灵长总目(Euarchontoglires)5 个目12 种动物的系统发育关系,结果支持兔形目(Lagomorpha)的单系起源,其中草兔与欧洲野兔(L. europaeus)亲缘关系最近,两者互为姐妹群,进而与家兔(Oryctolagus cuniculus)构成姐妹群关系。此外,基于线粒体细胞色素b 基因全序列,构建31 个兔类个体的系统发育关系,结果显示,草兔与雪兔(L. timidus),云南兔(L. comus) 与高原兔(L.oiostolus),东北兔(L. mandschuricus)与塔里木兔(L. yarkandensis) 有较近的亲缘关系,而在草兔内部,中国的草兔与南非草兔亲缘关系较远,采自江苏盐城的草兔与来自山东、陕西、四川的草兔聚为一支,具有明显较近的亲缘关系。该研究为更好地探讨草兔系统发育关系提供了进一步的分子生物学资料.     

斐豹蛱蝶线粒体基因组全序列的测定和分析(英文)

该研究对斐豹蛱蝶(Argyreus hyperbius)(鳞翅目:蛱蝶科)线粒体基因组全序列进行了测定和初步分析。结果表明:斐豹蛱蝶线粒体基因全序列全长为15156bp,包含13个蛋白质编码基因、22个tRNA和2个rRNA基因以及1个非编码的A+T富集区,基因排列顺序与其它鳞翅目种类一致;线粒体全序列核苷酸组成和密码子使用显示出明显的A+T偏好(80.8%)和轻微的AT偏移(AT skew,?0.019)。基因组中共存在11个2～52bp不等的基因间隔区,总长96bp;以及14个1～8bp不等的基因重叠区,总长34bp。除COI以CGA作为起始密码子外,13个蛋白质编码基因中的其余12个基因是以ATN作为起始密码子。除COI和COII基因是以单独的一个T为终止密码子,其余11个蛋白质编码基因都是以TAA结尾的。除了缺少DHU臂的tRNASer(AGN),其余的tRNA基因都显示典型的三叶草结构。tRNA(AGN)和ND1之间的基因间隔区包含一个ATACTAA结构域,这个结构域在鳞翅目中是保守的。A+T富集区没有较大的多拷贝重复序列,但是包含一些微小重复结构:ATAGA结构域下游的20bp poly-T结构,ATTTA结构域后的(AT)9重复,以及位于tRNAMet上游的5bp poly-A结构等。这项研究所揭示的斐豹蛱蝶的线粒体基因组特征,不仅为认识蛱蝶科的遗传多样性贡献数据,而且对于该物种的保护生物学、群体遗传学、谱系地理及演化研究等具有重要意义。     

Complete mitochondrial genome of the forensically important carrion beetle,Necrodes nigricornis (Coleoptera: Silphidae)

The carrion beetle, Necrodes nigricornis Harold, 1875 (Coleoptera: Silphidae) is one of the most frequently encountered insect species among Silphidae in animal cadavers in Korea. Consequently, the postmortem colonization of the species can provide useful information regarding the time-since-death. In this study, we report the mitochondrial genome (mitogenome) characteristics of N. nigricornis with the aim of increasing the genomic data pools of the family Silphidae, which is of considerable forensic importance. The full-length circular genome is 18,503 bp, with 75.60 % A/T content. It contains a typical set of 37 metazoan genes, but the non-coding A + T-rich region is unusually long at 3,818 bp in length, containing two similar-sized repeats (539 and 542 bp) with a slight length and nucleotide variation. The gene arrangement of the species is identical to that of the ancestral arrangement found in the majority of insects. The biased A/T content in the genome is also reflected in the form of biased codon usage; six codons among 62 comprised solely of A/T nucleotides (TTA, ATT, TTT, ATA, TTA, and TAT) were highly used, accounting for 41.28 % of the total. The maximum-likelihood tree built using 12 PCG (excluding ND2) and lrRNA revealed monophyletic Silphidae, Silphinae, and Nicrophorinae, with relatively higher nodal supports (bootstrap support ≥ 80 %). N. nigricornis, belonging to Silphinae, was placed as the sister to congeneric N. littoralis with the highest nodal support. We believe this mitogenome sequences of the carrion beetle can become an important baseline information for future studies on phylogeny at various levels of taxonomic diversity, intra-specific variation, as well as species identification.     

Phylogenetic relationships between tuna species of the genus Thunnus (Scombridae: Teleostei): Inconsistent implications from morphology,nuclear and mitochondrial genomes

In order to infer phylogenetic relationships between tuna species of the genus Thunnus, partial sequences of the mitochondrial cytochrome b and ATPase genes were determined in all eight species. Supplemental restriction analysis on the nuclear rRNA gene was also carried out. Pacific northern bluefin tuna (Thunnus thynnus orientalis) was found to have mtDNA distinct from that of the Atlantic subspecies (T. t. thynnus) but very similar to that from the species albacore (T. alaluga). In contrast, no differentiation in nuclear genome was observed between the Atlantic and Pacific northern bluefin tunas. The Atlantic northern bluefin and southern bluefin tunas possessed mtDNA sequences very similar to species of yellowfin tuna group and not so similar to albacore and bigeye tunas which were morphologically assigned to the bluefin tuna group. The molecular data indicate that (1) mtDNA from albacore has been incorporated into the Pacific population of northern bluefin tuna and has extensively displaced the original mtDNA, and (2) albacore is the earliest offshoot, followed by bigeye tuna in this genus, which is inconsistent with the phylogenetic relationships between these tuna species inferred from morphology. Correspondence to: S. Chow     

赤狐线粒体全基因组及系统发育分析

测定了赤狐的线粒体基因组全序列,总长度为16 723 bp,碱基组成为：31.3% A、26.1% C、14.8% G、27.8% T。和大多数哺乳动物一样,赤狐的线粒体全基因组包含13个蛋白质编码基因、2个核糖体RNA基因、22个转运RNA基因和1个控制区。除ND3基因起始密码子为不常见的ATT外,赤狐与北极狐、狼、家犬、郊狼的线粒体蛋白质编码遵循相同模式。在控制区的保守序列区段1和2之间发现一段较长的富含AC的随机重复序列。为了验证赤狐与其他犬科动物的系统发育关系,利用12个重链蛋白质编码基因,分别通过邻接法和最大简约法构建了系统发育树。结果表明：赤狐与北极狐是姐妹群,它们在犬科中都属于赤狐型分支,而灰狼、家犬和郊狼则属于狼型分支,与现有的系统进化研究结果一致。     

A hotspot of gene order rearrangement by tandem duplication and random loss in the vertebrate mitochondrial genome

Most reported examples of change in vertebrate mitochondrial (mt) gene order could be explained by a tandem duplication followed by random loss of redundant genes (tandem duplication-random loss [TDRL] model). Under this model of evolution, independent loss of genes arising from a single duplication in an ancestral species are predicted, and remnant pseudogenes expected, intermediate states that may remain in rearranged genomes. However, evidence for this is rare and largely scattered across vertebrate lineages. Here, we report new derived mt gene orders in the vertebrate "WANCY" region of four closely related caecilian amphibians. The novel arrangements found in this genomic region (one of them is convergent with the derived arrangement of marsupials), presence of pseudogenes, and positions of intergenic spacers fully satisfy predictions from the TDRL model. Our results, together with comparative data for the available vertebrate complete mt genomes, provide further evidence that the WANCY genomic region is a hotspot for gene order rearrangements and support the view that TDRL is the dominant mechanism of gene order rearrangement in vertebrate mt genomes. Convergent gene rearrangements are not unlikely in hotspots of gene order rearrangement by TDRL.     

Complete mitochondrial genome of the black‐tailed hornet,Vespa ducalis (Hymenoptera: Vespidae): Genomic comparisons in Vespoidea

We sequenced the complete mitochondrial genome (mitogenome) of the black‐tailed hornet, Vespa ducalis (Hymenoptera: Vespidae). The genome was 15,779‐bp long and contained typical sets of genes [13 protein‐coding genes (PCGs), 22 tRNAs, and 2 rRNAs]. The V. ducalis A + T‐rich region was 166‐bp long and was the shortest of all sequenced Vespoidea genomes, including Vespa. The genome was highly biased toward A/T nucleotides—80.1 % in the whole genome, 77.8 % in PCGs, 83.4–85.6 % in RNAs, and 92.8 % in the A + T‐rich region. These values are well within the typical range for genes and regions of Vespoidea mitogenomes. Start and stop codons in several Vespa species—including V. ducalis—were diversified, despite these species belonging to the same genus. In comparison with the ancestral mitogenomes, Vespa mitogenomes—including that of V. ducalis—showed substantial gene rearrangement; however, we detected no gene rearrangement among Vespa species. We conducted phylogenetic reconstruction based on concatenated sequences of 13 PCGs and two rRNAs (12,755 bp ) in available species of Vespoidea—21 species in six subfamilies in two families (Vespidae and Formicidae). The Bayesian inference and maximum likelihood (ML) methods revealed that each family formed strong monophyletic groups [Bayesian posterior probability (BPP) = 1; ML, 100 %]. Moreover, V. ducalis and V. mandarinia formed a strong sister group (BPP = 1; ML, 94 %).