Research Article |
Corresponding author: Yuehua Song ( songyuehua@163.com ) Academic editor: Mick Webb
© 2021 Xiaoxiao Chen, Can Li, Yuehua Song.
This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Citation:
Chen X, Li C, Song Y (2021) The complete mitochondrial genomes of two erythroneurine leafhoppers (Hemiptera, Cicadellidae, Typhlocybinae, Erythroneurini) with assessment of the phylogenetic status and relationships of tribes of Typhlocybinae. ZooKeys 1037: 137-159. https://doi.org/10.3897/zookeys.1037.63671
|
The number and classification of tribes in the leafhopper subfamily Typhlocybinae are not yet fully clear, and molecular data has recently been used to help resolve the problem. In this study, the mitochondrial genomes of Mitjaevia shibingensis Chen, Song & Webb, 2020 and M. dworakowskae Chen, Song & Webb, 2020 of the tribe Erythroneurini (Cicadellidae, Typhlocybinae) were sequenced. Most protein-coding genes (PCGs) start with ATN and end with TAA or TAG, and the AT content of these three codons were found differ from previous results that show that the first codon has the highest incidence. Two rRNA genes are highly conserved, and the AT content in 16S is higher than that of 12S. The nucleotide diversity and genetic distance among 13 PCGs of the four tribes from Typhlocybinae show that Empoascini nucleotide diversity is significantly less than in the other three tribes, and have the largest distance from the others, while Typhlocybini and Zyginellini have the smallest distance, indicating that the relationship between the two is the closest. The nad2, nad4, nad4L, and nad5 genes have greater nucleotide diversity, showing potential for use as the main markers for species identification. The phylogenetic analysis yielded a well-supported topology with most branches receiving maximum support and a few branches pertaining to relationships within Zyginellini and Typhlocybini receiving lower support. The species of these two tribes are intertwined, and it was impossible to resolve them into separate branches. In addition, the tribes Empoascini and Erythroneurini were recovered as monophyletic, and Alebrini was placed at the base of the tree as the most primitive. These results are broadly in line with other molecular phylogenetical studies which differ from traditional morphological classification.
Mitjaevia dworakowskae, Mitjaevia shibingensis, mitochondrial genome, phylogenetic analysis, tribal taxonomic status
Cicadellidae (leafhoppers) are the largest family of the order Hemiptera. Representatives are important agricultural and forestry pests that feed on a variety of plants such as cereal crops, vegetables, and fruit trees, and they are also vectors of plant pathogens (
The traditional classification of leafhopper has attracted much research attention, including the classification of Typhlocybinae. At present, Typhlocybinae contains six tribes (Alebrini, Empoascini, Erythroneurini, Zyginellini, Typhlocybini, Dikraneurini) but this division remains controversial (
The insect mitochondrial genome (mtDNA) is usually a closed double-stranded DNA molecule with a molecular weight of 14–20 kb. Usually, it contains 37 genes, including 13 protein-coding genes (PCGs), NADH dehydrogenase 1-6 and 4L (nad1-6 and nad4L), cytochrome c oxidase subunits 1-3 (cox1-3), ATPase subunit 6 and 8 (atp6 and atp8), cytochrome b (cytb), two ribosomal RNAs genes (16S and 12S) and 22 transfer RNA (tRNA) genes. A region rich in A + T, the control region, is also present (
To further enrich the mitochondrial genome data of leafhoppers and provide comparative data for closely related species, we sequenced and analyzed the complete mitochondrial genomes of Mitjaevia shibingensis and M. dworakowskae and analyzed their phylogenetic relationship with other Typhlocybinae. The new molecular data obtained will help in the identification of leafhopper species, kinship comparison, and future studies on population genetics and evolution.
For this study, samples of Mitjaevia shibingensis and M. dworakowskae were collected in 100% alcohol and stored at –20 °C in the laboratory. Total DNA was extracted from the entire body without the abdomen and wings. The mitochondrial gene sequences were obtained through second-generation sequencing. Primers were designed to amplify the mtDNA sequence in PCR reactions. The PCR reaction was performed using the LA Taq polymerase. The PCR conditions were as follows: initial denaturation at 94 °C for 2 min, then 35 cycles of denaturation at 94 °C for 30 sec, annealing at 55 °C for 30 sec, and extension at 72 °C for 1 min/kb, followed by the final extension at 72 °C for 10 min. The PCR products were sequenced directly, or, if needed, first cloned into a pMD18-T vector (Takara, JAP) and then sequenced, by the dideoxynucleotide procedure, using an ABI 3730 automatic sequencer (Sanger sequencing) using the same set of primers. After quality-proofing of the obtained fragments, the complete mt genome sequence was assembled manually using DNAStar (
The phylogenetic analysis included two sets of data. First, the phylogenetic tree was constructed based on 29 cox1 data among six tribes of Typhlocybiane and two outgroups. Secondly, phylogenetic tree analysis was conducted using a dataset including the complete mitochondrial genomes of the two newly sequenced erythroneurine species, 17 typhlocybiane species, and two outgroups, of which nine sets of data were from team sequencing, while the remaining 10 were obtained from the NCBI database (Table
Tribe | Species | Length (bp) | GenBank accession no. |
---|---|---|---|
Empoascini | Empoasca flavescens | 15,152 | MK211224.1 |
Empoasca onukii | 15,167 | NC_037210.1 | |
Empoasca vitis | 15,154 | NC_024838.1 | |
Ghauriana sinensis | 15,491 | MN699874.1 | |
Erythroneurini | Empoascanara dwalata | 15,271 | MT350235.1 |
Empoascanara gracilis | 14,627 | MT576649 | |
Empoascanara sipra | 14,827 | NC_048516.1 | |
Empoascanara wengangensis | 14,830 | MT445764 | |
Illinigina sp. | 14,803 | KY039129.1 | |
Mitjaevia dworakowskae | 16,399 | MT981880 | |
Mitjaevia protuberanta | 15,472 | NC_047465.1 | |
Mitjaevia shibingensis | 15,788 | MT981879 | |
Typhlocybini | Bolanusoides shaanxiensis | 15,274 | MN661136.1 |
Eupteryx minuscula | 16,944 | MN910279.1 | |
Typhlocyba sp. | 15,223 | KY039138.1 | |
Zyginellini | Limassolla lingchuanensis | 15,716 | MN605256.1 |
Paraahimia luodianensis | 16,497 | NC_047464.1 | |
Parathailocyba orla | 15,382 | MN894531.1 | |
Zyginella minuta | 15,544 | MT488436.1 |
The Gblocks Server online platform was used to eliminate poorly aligned positions and divergent regions of DNA protein alignment, and all alignments were checked and corrected in MEGA 6.06 prior to the phylogenetic analysis (
The trimmed datasets were used to estimate the phylogeny by maximum likelihood (ML) using IQ-TREE and Bayesian inference (BI) using MrBayes 3.2.7 (
The genomic organization and nucleotide composition of the two new mitogenomes sequenced in this study are similar to those of other previously reported Typhlocybina (
Organization of the Mitjaevia shibingensis and M. dworakowskae mitochondrial genome.
M. shibingensis/M. dworakowskae | |||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|
Gene | Position | Size (bp) | Intergenic | Start codon | Stop codon | Strand | |||||
tRNA-Ile | 1–63 | 1–63 | 63 | 0 | H | ||||||
tRNA-Gln | 61–128 | 61–128 | 68 | –3 | 0 | L | |||||
tRNA-Met | 151–219 | 137–205 | 69 | 8 | 9 | H | |||||
nad2 | 220–1191 | 206–1177 | 972 | 0 | ATA | TAA | H | ||||
tRNA-Trp | 1190–1253 | 1176–1235 | 64 | 60 | –2 | 2 | H | ||||
tRNA-Cys | 1246–1307 | 1233–1295 | 62 | 63 | –8 | L | |||||
tRNA-Tyr | 1307–1368 | 1299–1364 | 62 | 66 | 5 | 3 | L | ||||
cox1 | 1378–2913 | 1374–2909 | 1536 | 1 | 2 | ATG | TAA | TAG | H | ||
tRNA-Leu | 2915–2980 | 2911–2976 | 66 | 0 | 2 | H | |||||
cox2 | 2981–3659 | 2977–3655 | 679 | 0 | ATT | T | H | ||||
tRNA-Lys | 3660–3730 | 3656–3726 | 71 | 0 | H | ||||||
tRNA-Asp | 3733–3793 | 3727–3789 | 61 | 63 | –1 | 0 | H | ||||
atp8 | 3792–3944 | 3799–3942 | 153 | 144 | –1 | –2 | TTG | ATA | TAA | H | |
atp6 | 3938–4591 | 3936–4589 | 654 | –7 | 0 | ATG | TAA | H | |||
cox3 | 4592–5371 | 4590–5369 | 780 | 2 | 8 | ATG | TAA | H | |||
tRNA-Gly | 5376–5437 | 5370–5431 | 62 | 0 | H | ||||||
nad3 | 5438–5791 | 5432–5785 | 354 | 0 | ATT | ATA | TAA | H | |||
tRNA-Ala | 5796–5857 | 5791–5855 | 62 | 65 | 4 | –2 | H | ||||
tRNA-Arg | 5857–5921 | 5861–5922 | 65 | 62 | 2 | 15 | H | ||||
tRNA-Asn | 5912–5986 | 5922–5981 | 66 | 60 | –2 | 0 | H | ||||
tRNA-Ser | 5986–6053 | 5986–6052 | 68 | 67 | –4 | –1 | H | ||||
tRNA-Glu | 6055–6118 | 6058–6123 | 64 | 66 | 8 | 11 | H | ||||
tRNA-Phe | 6135–6197 | 6128–6195 | 63 | 68 | 4 | 2 | L | ||||
nad5 | 6200–7873 | 6200–7873 | 1674 | 0 | TTG | TAA | L | ||||
tRNA-His | 7874–7937 | 7874–7937 | 64 | 0 | L | ||||||
nad4 | 7937–9265 | 7937–9265 | 1329 | –7 | –1 | ATG | TAA | L | |||
nad4L | 9259–9537 | 9259–9537 | 279 | 1 | –7 | ATG | TAA | L | |||
tRNA-Thr | 9540–9605 | 9540–9604 | 66 | 65 | 2 | 0 | H | ||||
tRNA-Pro | 9606–9671 | 9605–9671 | 66 | 67 | 0 | 7 | L | ||||
nad6 | 9674–10159 | 9674–10159 | 486 | 2 | 5 | ATT | TAA | H | |||
cytb | 10166–11302 | 10162–11298 | 1137 | 7 | 0 | ATG | TAG | TAA | H | ||
tRNA-Ser | 11309–11372 | 11298–11363 | 64 | 66 | –2 | 9 | H | ||||
nad1 | 11363–12304 | 11366–12296 | 942 | 931 | –10 | –2 | ATT | TAA | T | L | |
tRNA-Leu | 12305–12370 | 12297–12364 | 66 | 68 | 0 | L | |||||
16S | 12371–13562 | 12365–13549 | 1192 | 1185 | 0 | L | |||||
tRNA-Val | 13563–13627 | 13550–13615 | 65 | 66 | 0 | L | |||||
12S | 13628–14359 | 13616–14351 | 732 | 736 | 0 | L | |||||
D-loop | 14360–15788 | 14352–16399 | 1429 | 2048 |
The AT contents and skew statistics are shown in Table
Nucleotide compositions, AT skew, and GC skew in different regions of Mitjaevia shibingensis and M. dworakowskae mitochondrial genomes.
Feature | A% | C% | G% | T% | A+T% | AT skew | GC skew | Length (bp) |
---|---|---|---|---|---|---|---|---|
M. shibingensis | ||||||||
Whole | 40.8 | 11.6 | 10.0 | 37.6 | 78.4 | 0.042 | –0.074 | 15,788 |
PCGs | 39.3 | 12.8 | 11.5 | 36.4 | 75.7 | 0.038 | –0.053 | 10975 |
1st codon position | 41.6 | 12.1 | 11.5 | 34.9 | 76.5 | 0.087 | –0.026 | 3659 |
2nd codon position | 38.3 | 12.2 | 11.7 | 37.8 | 76.1 | 0.007 | –0.018 | 3658 |
3rd codon position | 38.0 | 14.1 | 11.3 | 36.6 | 74.5 | 0.019 | –0.111 | 3658 |
tRNA | 40.6 | 10.9 | 10.1 | 38.4 | 79.0 | 0.028 | –0.037 | 1427 |
16S | 48.1 | 11.1 | 6.0 | 34.8 | 82.9 | 0.160 | –0.294 | 1192 |
12S | 48.0 | 12.0 | 6.1 | 33.9 | 81.8 | 0.172 | –0.323 | 732 |
CR | 42.7 | 3.5 | 3.8 | 50.0 | 92.7 | –0.079 | 0.038 | 1429 |
M. dworakowskae | ||||||||
Whole | 41.5 | 11.6 | 9.4 | 37.5 | 79.0 | 0.051 | –0.104 | 16,399 |
PCGs | 40.1 | 12.5 | 10.8 | 36.6 | 76.7 | 0.046 | –0.073 | 10955 |
1st codon position | 42.4 | 11.9 | 10.6 | 35.1 | 77.5 | 0.095 | –0.055 | 3652 |
2nd codon position | 38.0 | 12.9 | 11.7 | 37.3 | 75.4 | 0.009 | –0.047 | 3652 |
3rd codon position | 39.9 | 12.7 | 10.0 | 37.4 | 77.3 | 0.032 | –0.119 | 3651 |
tRNA | 40.6 | 11.6 | 9.9 | 37.9 | 78.5 | 0.034 | –0.081 | 1435 |
16S | 49.6 | 11.1 | 6.4 | 32.9 | 82.5 | 0.202 | –0.266 | 1185 |
12S | 47.6 | 11.1 | 6.9 | 34.4 | 81.9 | 0.161 | –0.233 | 736 |
CR | 43.1 | 6.9 | 4.2 | 45.8 | 88.9 | –0.030 | –0.246 | 2048 |
Similar to other Typhlocybinae mitochondrial genomes, of the 13 PCGs of M. shibingensis and M. dworakowskae, nine genes (cox1, cox2, cox3, atp8, atp6, nad2, nad3, nad6, and cytb) are located on the major strand (H-strand) while the other four PCGs (nad4, nad4L, nad5, and nad1) are located on the minor strand (L-strand). The largest gene was the nad5 gene, and the smallest was the atp8 gene in erythroneurine mitogenomes. The average AT content values of PCGs were 75.4% and 76.7% in M. shibingensis and M. dworakowskae, respectively. The A + T content of the first codon positions (76.5%, 77.5%) was much higher than that of the second (76.1%, 75.4%) and the third (74.5%, 77.3%) positions. This result was different from most other studies which show that the third codon has the highest AT content (
Research determined the behavior of the PCG codon families and found that codon usage was very similar among Cicadellidae mitogenomes when the results of two species were calculated and summarized (see Table
Codon and Relative Synonymous Codon Usage (RSCU) of 13 PCGs in the mt genomes of Mitjaevia shibingensis and M. dworakowskae.
Amino acid | Codon | Count/RSCU | Amino acid | Codon | Count/RSCU | ||||||
---|---|---|---|---|---|---|---|---|---|---|---|
M. shibingensis | M. dworakowskae | M. shibingensis | M. dworakowskae | ||||||||
Phe | UUU | 190 a | 1.49 | 200 | 1.5 | Tyr | UAU | 190 | 1.56 | 185 | 1.57 |
UUC | 65 | 0.51 | 66 | 0.5 | UAC | 53 | 0.44 | 51 | 0.43 | ||
Leu2 | UUA | 234 | 3.15 | 245 | 3.33 | His | CAU | 57 | 1.37 | 49 | 1.48 |
UUG | 63 | 0.85 | 45 | 0.61 | CAC | 26 | 0.63 | 17 | 0.52 | ||
Leu1 | CUU | 46 | 0.62 | 39 | 0.53 | Gln | CAA | 56 | 1.58 | 66 | 1.71 |
CUC | 28 | 0.38 | 20 | 0.27 | CAG | 15 | 0.42 | 11 | 0.29 | ||
CUA | 56 | 0.75 | 69 | 0.94 | Asn | AAU | 269 | 1.49 | 281 | 1.54 | |
CUG | 19 | 0.26 | 24 | 0.33 | AAC | 91 | 0.51 | 84 | 0.46 | ||
Ile | AUU | 226 | 1.5 | 225 | 1.55 | Lys | AAA | 242 | 1.62 | 246 | 1.57 |
AUC | 75 | 0.5 | 66 | 0.45 | AAG | 56 | 0.38 | 67 | 0.43 | ||
Met | AUA | 201 | 1.58 | 213 | 1.68 | Asp | GAU | 35 | 1.32 | 35 | 1.52 |
AUG | 54 | 0.42 | 40 | 0.32 | GAC | 18 | 0.68 | 11 | 0.48 | ||
Val | GUU | 52 | 1.66 | 53 | 1.93 | Glu | GAA | 56 | 1.51 | 62 | 1.65 |
GUC | 12 | 0.38 | 11 | 0.4 | GAG | 18 | 0.49 | 13 | 0.35 | ||
GUA | 47 | 1.5 | 41 | 1.49 | Cys | UGU | 27 | 1.26 | 37 | 1.42 | |
GUG | 14 | 0.45 | 5 | 0.18 | UGC | 16 | 0.74 | 15 | 0.58 | ||
Ser2 | UCU | 47 | 1.29 | 48 | 1.28 | Trp | UGA | 49 | 1.24 | 54 | 1.33 |
UCC | 19 | 0.52 | 11 | 0.29 | UGG | 30 | 0.76 | 27 | 0.67 | ||
UCA | 66 | 1.81 | 81 | 2.15 | Arg | CGU | 14 | 1.27 | 13 | 1.44 | |
UCG | 8 | 0.22 | 5 | 0.13 | CGC | 5 | 0.45 | 2 | 0.22 | ||
Pro | CCU | 26 | 1.11 | 42 | 1.65 | CGA | 20 | 1.82 | 14 | 1.56 | |
CCC | 30 | 1.28 | 27 | 1.06 | CGG | 5 | 0.45 | 7 | 0.78 | ||
CCA | 34 | 1.45 | 31 | 1.22 | Ser1 | AGU | 53 | 1.46 | 48 | 1.28 | |
CCG | 4 | 0.17 | 2 | 0.08 | AGC | 16 | 0.44 | 26 | 0.69 | ||
Thr | ACU | 49 | 1.26 | 54 | 1.26 | AGA | 53 | 1.46 | 51 | 1.36 | |
ACC | 42 | 1.08 | 38 | 0.89 | AGG | 29 | 0.8 | 31 | 0.82 | ||
ACA | 55 | 1.41 | 63 | 1.47 | Gly | GGU | 31 | 1.11 | 34 | 1.31 | |
ACG | 10 | 0.26 | 16 | 0.37 | GGC | 15 | 0.54 | 10 | 0.38 | ||
Ala | GCU | 26 | 1.89 | 23 | 1.74 | GGA | 25 | 0.89 | 31 | 1.19 | |
GCC | 6 | 0.44 | 9 | 0.68 | GGG | 41 | 1.46 | 29 | 1.12 | ||
GCA | 18 | 1.31 | 19 | 1.43 | * | UAA | 177 | 1.61 | 170 | 1.61 | |
GCG | 5 | 0.36 | 2 | 0.15 | UAG | 43 | 0.39 | 41 | 0.39 |
All 22 typical tRNA genes are present in the M. shibingensis and M. dworakowskae mitochondrial genomes, of which 14 genes were oriented on the major strand (H-strand), whereas the others were transcribed on the minor strand (L-strand). Their nucleotide lengths are almost identical between species, ranging from 60 bp to 71 bp (Table
Leafhopper ribosomal RNA (rRNA) includes 16S RNA and 12S RNA. These two genes are highly conserved and are encoded on the minor strand (L-strand). Similar to other known insects, the content of A + T% in 16S was higher than that of 12S. The 16s genes of M. shibingensis and M. dworakowskae were 1192 bp and 1852 bp in length, with AT contents of 82.90% and 82.50%, respectively, and located between trnL2 and trnV. The 12S rRNA genes of both were 732 bp and 736 bp in length, with AT contents of 81.80% and 81.90%, respectively, and located after trnV. The rRNA genes showed a positive AT skew and negative GC skew (Table
Like the typical insect mitochondrial genome, the mt genomes of M. shibingensis and M. dworakowskae have a large non-coding region, which was identified as the control region and located downstream of 12S. Control regions of both species were rich in AT, with lengths of 1429 bp and 2048 bp AT contents of 92.7% and 88.9%, respectively (Table
The sliding window analysis shows highly variable nucleotide diversity (Pi values) among 13 PCGs sequences of the four tribes of Typhlocybinae (Fig.
Empoascini | Typhlocybini | Zyginellini | |
Typhlocybini | 0.3663 | ||
Zyginellini | 0.3645 | 0.2663 | |
Erythroneurini | 0.3623 | 0.3288 | 0.3262 |
Nucleotide diversity analysis, a primary method for identifying the regions with large nucleotide divergence, is especially useful for designing species-specific markers. These are useful for taxa with highly variable morphological characteristics, especially Typhlocybinae species which belong to groups that are difficult to distinguish by morphology alone (
Typhlocybinae has been divided into tribes based mainly on the characteristics of the wing veins for the past 90 years. Melichar (1903),
In recent years, molecular sequencing technology has been widely used in phylogenetic analysis, which can test and verify the results of different levels of more morphology based traditional classifications. Within Typhlocybinae, only a few studies have used the combination of morphological characteristics and molecular data to construct phylogenetic relationships. The amount of data is sparse at present and further data is needed.
Dietrich and Dmitriev (2006) used PAUP 4.0b10 to analyze the phylogeny of Typhlocybinae for the first time based on morphological characteristics and concluded that Erythroneurini and Dikraneurini are closely related. However, their analysed samples came mainly from the New World, and whether their results represent the relationship between the tribes of Typhlocybinae remains to be clarified.
This study, based on 29 species of cox1, 19 species of 13 PCGs, and two rRNA mitochondrial genes data of Typhlocybinae produced a slightly different result to the traditional classification with respect to Typhlocybini and Zyginellini. Maximum Likelihood (ML) method was used with IQ-TREE using an ultrafast bootstrap approximation approach with 10,000 replicates. The Bayesian Inference (BI) analysis was performed using MrBayes 3.2.7, with the best fit model GTR+I+ G (Vogler and DeSalle 1993).
Cox1 is one of the mitochondrial protein-coding genes and its bi-terminal sequence is more conservative than cox2. It has a rapid evolution rate and large differences between species, and can provide rich phylogenetic information, hence is an ideal mitochondrial molecular marker. The gene sequences were obtained in the current study by downloading the cox1 gene sequence of 29 species of Typhlocybinae and two outgroups of Idiocerinae from NCBI to construct a phylogenetic tree. BI and ML analyses generated the same tree topology: (Alebrini + Empoascini) + (Erythroneurini + ((Zyginellini + Typhlocybini) + Dikraneurini))). Most relationships were highly supported, and a few branches pertaining to relationships within Zyginellini and Typhlocybini received lower support (Fig.
At present, the complete mitochondrial genome data of Alebrini and Dikraneurini have not been added to NCBI. Thus, the phylogenetic relationships were analyzed based on the concatenated nucleotide sequences of 13 PCGs and two rRNA from 19 Typhlocybinae (the remaining four tribes) species and two outgroups. Although ML and PB analyses produced inconsistent topologies across the different datasets and models, most relationships were highly supported and consistent in the analyses, and the main difference is the relationship of species between Zyginellini and Typhlocybini. (Figs
This paper describes the complete mitochondrial genomes of M. shibingensis and M. dworakowskae, analyzes the basic composition, location, secondary structure, and other characteristics of PCGs, tRNA genes, rRNA genes, and control regions, and compares them to other Typhlocybinae mitochondrial genomes. The mitogenomes of these two species closely resemble those of most other sequenced leafhoppers in various structural and compositional aspects. The sliding window analysis shows a highly variable nucleotide diversity (Pi values) among 13 PCGs sequences of the four tribes of Typhlocybinae. Empoascini nucleotide diversity is significantly lower than in the other three tribes, and the other three tribes have little difference between them. The genes nad2, nad4, nad4L, and nad5 have higher nucleotide diversity, and whether they can be used as the main markers for species identification or the main related genes that control the appearance of the subfamily is worthy of further study. The genetic distance of the four tribes of Typhlocybinae shows that the Empoascini and the other three tribes are the largest while Typhlocybini and Zyginellini are the smallest and indicates that the relationship between the two is the closest, which is consistent with the results of morphological studies. Phylogenetic analysis of 31 cox1 yielded a well-supported topology with most branches receiving maximum support and a few branches pertaining to relationships within Zyginellini and Typhlocybini receiving lower support; the species of these two tribes are intertwined and cannot be resolved into separate branches, and Alebrini is placed at the base of the tree as the most primitive. Phylogenetic relationships were analyzed based on the concatenated nucleotide sequences of 13 PCGs and two rRNA show that although ML and PB analyses produced inconsistent topologies across the different datasets and models, and most relationships were highly supported and constant in the analyses. In this study, Empoascini and Erythroneurini were recovered as monophyletic while Zyginellini and Typhlocybini gathered into a single branch and Empoascini tended to be placed at the basal position of the tree as the sister group to the other tribes. This study indicated that mitochondrial genome sequences are informative for leafhopper phylogeny, but unlike the previous analysis (
Based on the current and previous studies, the classification of the tribes of Typhlocybinae is not yet fully resolved with respect to Typhlocybini and Zyginellini, i.e., one or two tribes. From a molecular perspective, more sequencing data is needed to build a more complete phylogenetic tree to support or modify the traditional morphological classification. To this aim, it is hoped that the new data provided here will facilitate future comparative studies of leafhopper mitogenomes and demonstrate the need for more comparative data.
We thank Chris Dietrich for reviewing the manuscript and Mick Webb for checking and revising the manuscript. This work was funded partly by the World Top Discipline Program of Guizhou Province: Karst Ecoenvironment Sciences (No. 125 2019 Qianjiao Keyan Fa), the Guizhou Provincial Science and Technology Foundation ([2018]1411), the Guizhou Science and Technology Support Project ([2019]2855), the Science and Technology Project of Guiyang City ([2020]7-18), the Innovation Group Project of Education Department of Guizhou Province ([2021]013), the Training Program for High-level Innovative Talents of Guizhou Province ([2016]4020) and the Project for Regional Top Discipline Construction of Guizhou Province: Ecology in Guiyang University (Qianjiao Keyan Fa [2017]85).
Datasets of phylogenetic analysis
Data type: phylogenetic