Genomic analysis and phylogenetic characterization of Himalayan snow trout, Schizothorax esocinus based on mitochondrial protein-coding genes.

BACKGROUND: Mitochondrial DNA (mtDNA) has become a significant tool for exploring genetic diversity and delineating evolutionary links across diverse taxa. Within the group of cold-water fish species that are native to the Indian Himalayan region, Schizothorax esocinus holds particular importance due to its ecological significance and is potentially vulnerable to environmental changes. This research aims to clarify the phylogenetic relationships within the Schizothorax genus by utilizing mitochondrial protein-coding genes. METHODS: Standard protocols were followed for the isolation of DNA from S. esocinus. For the amplification of mtDNA, overlapping primers were used, and then subsequent sequencing was performed. The genetic features were investigated by the application of bioinformatic approaches. These approaches covered the evaluation of nucleotide composition, codon usage, selective pressure using nonsynonymous substitution /synonymous substitution (Ka/Ks) ratios, and phylogenetic analysis. RESULTS: The study specifically examined the 13 protein-coding genes of Schizothorax species which belongs to the Schizothoracinae subfamily. Nucleotide composition analysis showed a bias towards A + T content, consistent with other cyprinid fish species, suggesting evolutionary conservation. Relative Synonymous Codon Usage highlighted leucine as the most frequent (5.18%) and cysteine as the least frequent (0.78%) codon. The positive AT-skew and the predominantly negative GC-skew indicated the abundance of A and C. Comparative analysis revealed significant conservation of amino acids in multiple genes. The majority of amino acids were hydrophobic rather than polar. The purifying selection was revealed by the genetic distance and Ka/Ks ratios. Phylogenetic study revealed a significant genetic divergence between S. esocinus and other Schizothorax species with interspecific K2P distances ranging from 0.00 to 8.87%, with an average of 5.76%. CONCLUSION: The present study provides significant contributions to the understanding of mitochondrial genome diversity and genetic evolution mechanisms in Schizothoracinae, hence offering vital insights for the development of conservation initiatives aimed at protecting freshwater fish species.

Swimming ability of Schizothoracinae fishes in Yarlung Zangbo River of China.

The Yarlung Zangbo River is a river with abundant hydropower resources but fragile biodiversity in China. As an important benchmark for both research and ecological management, there is still a lack of knowledge about the swimming ability of fishes in the Yarlung Zangbo River. The induced flow velocity (Uind), critical swimming speed (Ucrit), and burst swimming speed (Uburst) of five Schizothoracinae species were tested in this study. Relative swimming ability related to body length and body shape was calculated. The results indicated that the average absolute swimming speeds (Uind-a, Ucrit-a, and Uburst-a) of all the experimental fish were 10.20 ± 0.01, 57.58 ± 3.28, and 69.54 ± 2.94 cm/s, respectively, and the corresponding relative Uind, Ucrit, and Uburst related to body length (Uind-l, Ucrit-l, Uburst-l) were 1.15 ± 0.07, 5.04 ± 0.26, and 7.23 ± 0.28 BL/s, respectively. Moreover, relative Uind, Ucrit, and Uburst related to body shape (Uind-s, Ucrit-s, and Uburst-s) were 0.80 ± 0.13, 2.49 ± 0.51, and 4.32 ± 0.57 cm-2/s, respectively. No significantly differences in relative swimming speeds existed among five species. Only Oxygymnocypris stewartii was significantly weaker in Uburst-s than Schizothorax o'connori. The body shape showed a stronger relationship with swimming speed than the body length did. Schizothoracinae fish in the Yarlung Zangbo River basin are less sensitive to the water flow and performed weaker Ucrit and Uburst compared to those in the Yangtze River basin, indicating that Schizothoracinae fish in the Yarlung Zangbo River may be more susceptible to threats from environmental changes. The paper enriched the research on the swimming ability of Schizothoracinae fishes and provided efficient data for the fish conservation in the Yarlung Zangbo River.

Swimming ability of cyprinid species (subfamily schizothoracinae) at high altitude.

The primary objective of this investigation was to study the effect of altitude on fish swimming ability. Different species were tested to ensure that the differences observed are not associated with a single species. Fish critical swimming speed and burst speed were determined using stepped-velocity tests in a Brett-type swimming respirometer. Based on the effects of water temperature and dissolved oxygen, it is clear that the swimming ability of fish decreases as altitude increases. Further, because the effects of high altitude on fish physiology go beyond the effects of lower temperature and dissolved oxygen, we recommend that fish swimming ability be tested at an altitude similar to the target fishway site to ensure the validity of fish data used for fishway design.

Resolving the phylogenetic relationship of Himalayan snow trout Schizothorax plagiostomus with other species of Schizothoracine using mitochondrial CO-I and Cyt b genes.

BACKGROUND: The classification of the sub-family Schizothoracinae has been debatable due to the overlap in morphological characters. There are discrepancies between classical taxonomy and molecular taxonomy, as well. In the present study, mitochondrial genes CO-I and Cyt b were sequenced to elucidate the phylogenetic status of three species of the genus Schizothorax. METHODS AND RESULTS: In total, 29 samples of three species viz., S. plagiostomus, S. progastus, and S. richardsonii, were collected from rivers of Uttarakhand, India. For phylogenetic analyses, 40 sequences of CO-I and 41 sequences of Cyt b of Schizothoracinae species were downloaded from NCBI. The highest genetic divergence based on CO-I (16.08%) is between S. plagiostomus and Ptychobarbus dipogon, while the lowest divergence (0.00%) is between 10 pairs of species. The highest divergence based on Cyt b (19.43%), is between S. niger and Gymnocypris eckloni, while the lowest divergence (0.00%) is between four pairs of species. The divergence (0.00% for CO-I and 2.38% for Cyt b) between S. chongi and S. kozlovi, seems a case of convergent molecular evolution of the CO-I gene and in this case, CO-I alone cannot be used to differentiate these two species. CONCLUSION: The simultaneous use of two molecular markers along with morphomeristic data is a better strategy for the classification of the sub-family Schizothoracinae. These results will be a resource dataset for determining the taxonomical status of Schizothoracine species and will help in the conservation and commercial production of these commercially important fish species.

Hb adaptation to hypoxia in high-altitude fishes: Fresh evidence from schizothoracinae fishes in the Qinghai-Tibetan Plateau.

Uncovering the genetic basis of hypoxic adaptation is one of the most active research areas in evolutionary biology. Among air-breathing vertebrates, modifications of hemoglobin (Hb) play a pivotal role in mediating an adaptive response to high-altitude hypoxia. However, the relative contributions in water-breathing organisms are still unclear. Here, we tested the Hb concentration of fish at different altitudes. All species showed species-specific Hb concentration, which has a non-positive correlation with altitude. Moreover, we investigated the expression of Hb genes by the RNA-seq and quantitative real-time PCR (qRT-PCR), and Hb composition by two-dimensional electrophoresis (2-DE). The results showed that the multiple Hb genes and isoforms are co-expressed in schizothoracinae fishes endemic to the Qinghai-Tibetan Plateau (QTP). Phylogenetic analyses of Hb genes indicated that the evolutionary relationships are not easily reconciled with the organismal phylogeny. Furthermore, evidence of positive selection was found in the Hb genes of schizothoracinae fishes through the selection pressure analysis. We demonstrated that positively selected sites likely facilitated the functional divergence of Hb isoforms. Taken together, this study indicated that the long-term maintenance of high Hb concentration may be a disadvantage for physiologically acclimating to high altitude hypoxia. Meanwhile, the genetically based modification of Hb-O2 affinity in schizothoracinae fishes might facilitate the evolutionary adaptation to Tibetan aqueous environments.

Complete mitochondrial genome and phylogenetic analysis of Schizothorax sinensis (Teleostei: Cypriniformes: Cyprinidae).

This study describes the first sequencing of the complete mitochondrial genome of Schizothorax sinensis, a species of cyprinid snowtrout from the Jialing River and Fujiang River basins in China's Sichuan Province. The total length is 16,571 base pairs. Similar to most Schizothoracinae mitochondrial genomes, there are 37 genes including 13 protein coding genes, 22 transfer RNA genes and 2 ribosomal RNA genes. In addition, it contains a control region rich in A-T nucleotides. The overall nucleotide composition is 29.6% for A, 27.1% for C, 17.9% for G and 25.4% for T, and the percentage of GC content is 45.0%. Phylogenetic analysis suggested that Schizothorax sinensis and Schizothorax prenanti clustered together in a clade. This work provides additional molecular information for studying Schizothorax sinensis conservation genetics and evolutionary relationships.

Genomic signature of accelerated evolution in a saline-alkaline lake-dwelling Schizothoracine fish.

Tibetan Plateau imposes extremely inhospitable environment on most wildlife. Besides the harsh aquatic environment including hypoxia and chronic cold, high salinity and alkalinity is an increasing threat to Tibetan endemic fishes. Previous genome-wide studies identified key genes contributed to highland fish adaptation to hypoxia and long-term cold, while our understanding of saline and alkaline adaptation in Tibetan fish remains limited. In this study, we performed a comparative genomics analysis in a saline lake-dwelling highland fish Gymnocypris przewalskii, aimed to identify candidate genes that contributed to saline and alkaline adaptation. We found elevated genome-wide rate of molecular evolution in G. przewalskii relative to lowland teleost fish species. In addition, we found nine genes encoding biological macromolecules associated with ion transport functions underwent accelerated evolution in G. przewalskii, which broadly expressed across kidney, gill, liver, spleen, brain and muscle tissues. Moreover, we found putative evidence of ion transport under selection was interacted by co-expression in G. przewalskii adaptation to high salinity and alkalinity environment of Lake Qinghai. Taken together, our comparative genomics study identified a set of rapidly evolving ion transport genes and transcriptomic signatures in Schizothoracine fish adaptation to saline and alkaline environment on the Tibetan Plateau.

DNA barcodes and their characteristic diagnostic sites analysis of Schizothoracinae fishes in Qinghai province.

The Qinghai-Tibetan Plateau (QTP), the source and upper reaches of many Asian rivers, are crisscrossed by rivers and dotted with lakes. Schizothoracinae fishes, species native to the QTP, are distributed widely through these rivers and lakes. Over the past decades, ecological protection has become increasingly intense. The rapid acquisition of the genetic information and accurate gene sequence database are assumed to play an important role in the conservation of species diversity and biodiversity. In this study, 153 COI sequences (648bp in length) covering 13 species in 8 genera of Schizothoracinae fishes in Qinghai Province were used to determine whether barcode could identify Schizothoracinae species accurately. The average Kimura two parameter (K2P) genetic distances within and among species were 0.35% and 8.83%, respectively. The maximum K2P distance within species was observed in Gymnocypris eckloni (1.36%) while minimum K2P distance among species was observed between Chuanchia labiosa and Schizopygopsis pylzovi (0.23%). Overlaps existed in K2P distance intra- and inter- species based on both the genes. Eleven groups with 9 single-species groups and 2 multi-species groups were identified through Automatic Barcode Gap Discovery System, which were consistent with the overlaps of K2P distance. 96.7% as the accurate ratio for COI barcode was calculated and high solution was observed in the phylogenetic trees based on COI gene and Cyt b gene. Except for the similar results based on two genes above, COI barcode was more economical than Cyt b gene. The SOM model successfully predicted characteristic-diagnostic sites at species level: 36 characteristic-diagnostic sites from eight species, in which 12 from Gmnodiptychus pachycgeilus, 2 from Platypharodon extremus, 7 from Ptychobarbus kaznakovi, 2 from Schizopygopsis anteroventris, 2 from Schizopygopsis malacanthus, 3 from Schizopygopsis malacanthus chengi, 3 from Schizothorax dolichonema and 5 from Schizothorax lantsangensis. Our results show that Schizothoracinae fishes can be identified validly by using COI DNA barcode. Thirty-six characteristic-diagnostic sites were proposed to be applied into works of species identification for the Schizothoracinae fishes in Qinghai Province.

Convergent evolution misled taxonomy in schizothoracine fishes (Cypriniformes: Cyprinidae).

Highly specialized grade (HSG; genera Gymnocypris, Oxygymnocypris, Schizopygopsis, Platypharodon and Chuanchia) of the Schizothoracinae (Cypriniformes: Cyprinidae) are endemic to the Qinghai-Tibet Plateau (QTP). Previously, two distinct ecomorphs were recognized according to trophic traits. One was a limnetic omnivore with normal lower jaw morphology, terminal mouth, and moderate or dense gill rakers, mostly inhabiting in open water of lakes, including Gymnocypris and Oxygymnocypris. Another was a benthic feeder with inferior mouth, sparse gill rakers and sharp horny sheath on the lower jaw for scraping of attached prey off hard substrates, including Schizopygopsis, Platypharodon and Chuanchia. However, traditional taxonomy of HSG based on these trophic traits presented extensive conflicts with the molecular studies in recent years. The possible cause could be convergent evolution in morphology, retention of ancestral polymorphisms or mitochondrial introgression, but these hypotheses could not be assessed due to incomplete taxon sampling and only mitochondrial data employed in previous works. Here, we conducted the most comprehensive molecular analysis on HSG fishes to date, using four mitochondrial loci and 152,464 genome-wide SNPs, and including 21 of 24 putative species and one undescribed Schizopygopsis species. Both SNP and mtDNA trees confirmed extensive paraphyly of genera Gymnocypris and Schizopygopsis, where species often were clustered together by watershed instead of by genus. Basal split into the north clade B and the south clade C (ca. 3.03 Ma) approximately by the Tanggula-Tanitawen Mountains in SLAF tree coincided with a violent uplift of the QTP during the phase A of 'Qingzang movement' (ca. 3.6 Ma). Ancestral state reconstruction of the trophic ecomorph showed that the limnetic omnivore ecomorph had evolved repeatedly in clade B and C. Furthermore, we presented a striking case of convergent evolution between two 'subspecies' Gymnocypris chui chui and G. chui longimandibularis, which had diverged as early as two million years ago (ca. 2.42 Ma). Ecological analyses revealed that similar food utilization, particularly in zooplankton, was the main underlying driving force. This work showed an example of taxonomy with the most extensive errors at the genus/species levels due to convergent evolution and suggested that trophic traits could be misleading in fish taxonomy. Therefore, we propose a major generic revision for HSG species.

Genomic signature of highland adaptation in fish: a case study in Tibetan Schizothoracinae species.

BACKGROUND: Genome-wide studies on highland adaptation mechanism in terrestrial animal have been widely reported with few available for aquatic animals. Tibetan Schizothoracinae species are ideal model systems to study speciation and adaptation of fish. The Schizothoracine fish, Gymnocypris przewalskii ganzihonensis had underwent the ecological niche shift from salt water to freshwater, and also experienced a recent split from Gymnocypris przewalskii przewalskii. In addition, G. p. ganzihonensis inhabited harsh aquatic environment including low temperature and hypoxia as well as other Schizothoracinae species, its genetic mechanism of highland adaptation have yet to be determined. RESULTS: Our study used comparative genomic analysis based on the transcriptomic data of G. p. ganzihonensis and other four fish genome datasets to investigate the genetic basis of highland adaptation in Schizothoracine fish. We found that Schizothoracine fish lineage on the terminal branch had an elevated dN/dS ratio than its ancestral branch. A total of 202 gene ontology (GO) categories involved into transport, energy metabolism and immune response had accelerated evolutionary rates than zebrafish. Interestingly, we also identified 162 genes showing signature of positive selection (PSG) involved into energy metabolism, transport and immune response in G. p. ganzihonesis. While, we failed to find any PSG related to hypoxia response as previous studies. CONCLUSIONS: Comparative genomic analysis based on G. p. ganzihonensis transcriptome data revealed significant genomic signature of accelerated evolution ongoing within Tibetan Schizothoracinae species lineage. Molecular evolution analysis suggested that genes involved in energy metabolism, transport and immune response functions in Schizothoracine fish underwent positive selection, especially in innate immunity including toll-like receptor signaling pathway genes. Taken together, our result as a case study in Schizothoracinae species provides novel insights in understanding the aquatic animal adaptation to extreme environment on the Tibetan Plateau, and also provides valuable genomic resource for further functional verification studies.

Comprehensive transcriptomic analysis of Tibetan Schizothoracinae fish Gymnocypris przewalskii reveals how it adapts to a high altitude aquatic life.

BACKGROUND: Understanding the genetic basis of adaptation to high altitude life is of paramount importance for preserving and managing genetic diversity in highland animals. This objective has been addressed mainly in terrestrial fauna but rarely in aquatic animals. Tibetan Schizothoracinae fish is the ideal model system in evolutionary biology, carrying key insights into evolutionary genetics of speciation and adaptation at high altitude. Gymnocypris przewalskii is the newly formed Schizothoracinae fish species in the Tibetan Plateau, inhabits chronic cold, extreme saline and alkaline aquatic environment in Lake Qinghai, thus evolving the unique genomic signatures to adapt extremely severe environments. RESULTS: To characterize its genomic features, we assembled de novo transcriptome of G. przewalskii from Lake Qinghai. Intriguingly, by comparative genomic analyses of G. przewalskii and 8 other fish species, we identified potential expansions in gene families related to energy metabolism, transport and developmental functions, possibly underlying the adaptation to these environmental stresses. Through comprehensive molecular evolution analyses, we found that sets of genes controlling mitochondrion, ion homoeostasis, acid-base balance and innate immunity show significant signals of positive selection. Compared to previous studies on highland fishes, we failed to identify any positively selected genes related to hypoxia response. CONCLUSIONS: Our findings provide comprehensive insights into the genetic basis of teleost fish that underlie their adaptation to extreme high altitude aquatic life on the Tibetan Plateau.

The complete mitochondrial genome of the Ptychobarbus kaznakovi (Cyprinidae: Schizothoracinae).

Ptychobarbus kaznakovi is endemic to the Qinghai-Tibet Plateau in China. The complete mitochondrial genome of P. kaznakovi was sequenced and characterized. The genome is 16 700 bp in length and contains 13 protein-coding genes, 2 ribosomal RNAs, 22 transfer RNAs, and a non-coding control region. The gene arrangement and nucleotide composition of the mitochondrial genome are similar to those of Cyprinidae fish. A 2 bp tandem repeat was identified in the control region. We conclude that the control region is variable in length between and within species. The complete mitochondrial DNA in this study should be used in the studies on population genetics and phylogeny of P. kaznakovi.

The complete mitochondrial genome organization of Schizothorax Plagiostomus (Teleostei: Cyprinidae) from Northern Pakistan.

Schizothorax plagiostomus, a fresh water fish, is an economically important fish of Pakistan. In this study, the complete mitochondrial DNA (mtDNA) sequence of S. plagiostomus was explored. The mitogenome length was found to be 16 563bp with 13 protein-coding genes, 22 tRNA genes, 2 rRNA genes and 2 non-coding regions: origin of light-strand replication (OL) and control region (D-loop). All genes were encoded on the heavy strand except ND6 and few tRNA genes. The overall base composition of S. plagiostomus of the heavy strand was T 25.5%, C 27.0%, A 29.8% and G 17.8%, A + T content 55.3% and G + C content 44.7%. The phylogenetic tree suggests that S. esocinus, S. progastus, S. richardsonii and S. plagiostomus may have closer affinities than other fish of the genus Schizothorax. This mitogenome sequence would be useful for phylogenetic analysis and conservation of this species in Pakistan.

The mitochondrial genome of Schizothorax esocinus (Cypriniformes: Cyprinidae) from Northern Pakistan.

The mitochondrial DNA sequence represents a mainstay of phylogenetics. It allows biologists to elucidate the evolutionary relationships among species. It also permits an examination of the relatedness of populations, hence got importance in the field of biology. The current study was designed to know the mitochondrial sequence of Schizothorax esocinus, a delicious fish belonging to family Cyprinidae. In this study, the complete mitochondrial genome of S. esocinus from Northern Pakistan was determined. The mitogenome of S. esocinus was found to be 16 591 bp in length and consisted of 13 protein coding genes, 22 tRNA genes, two rRNA genes, and one control region. All genes were encoded on heavy strain except ND6 and few tRNA genes. The overall base composition was T 25.5%, C 27.0%, A 29.8% and G 17.7%, A + T content 55.3% and G + C content 47.7%. The length of control region (CR) was 938 bp and contained putative termination-associated sequence (TAS) and several conserved sequence blocks (CSB) and control region also contained a microsatellite region (TA). This is the very first study reported from a reservoir of large cold water bodies in Pakistan which have a great potential for conservation of cold water fish species. This mitogenome sequence would be useful to know the phylogenetic status of the fish.

The complete mitochondrial genome sequence of Herzensteinia microcephalus (Cypriniformes: Cyprinidae).

Herzensteinia microcephalus (Herzenstein, 1891) is the highest naturally occurring cyprinid in the world, and inhabits rivers in the Tibetan Plateau at elevations of 4500-5200 m. Few studies on this species have been contributed. In this study, we got the mitochondrial genome sequences of H. microcephalus. The mitogenome of H. microcephalus is16,726 in length, which includes 13 protein-coding genes, 22 tRNA genes, two rRNA genes and two non-coding regions: control region (D-loop) and origin of light-strand replication (OL). The overall nucleotide base composition is 28.41% for A, 27.16% for T, 26.04% for C and 18.38% for G. This study can provide important molecular theory basis for carrying out the study on the genetics, phylogeny and adaptive evolution of Herzensteinia.

The complete mitochondrial genome sequence of Platypharodon extremus (Cypriniformes: Cyprinidae).

Platypharodon extemus is a monotypic species of Schizothoracine fishes and it was listed as Endangered species in the "China Red Data Book (Pisces)", Vulnerable (V) by the National Environmental Protection Agency and Endangered Species Scientific Commission. So far, little mitochondrial genome information of this genus has been described. In this study, we obtained the complete mitochondrial DNA genome sequences of this species. The mitogenome was 16,668 bp in length, which consists of 13 protein-coding genes, 22 tRNA genes, 2 rRNA genes and 2 noncoding regions. The base composition of this mitochondrial genome was 28.6% A, 27.3% T, 18.2% G, 25.9% C, with a high A + T content (55.9%). The complete mitochondrial genome of P. extremus would be of great utility in the phylogenetic analysis of the schizothoracine fishes and also provide meritorious insights into the deeper problems of the phylogenic analysis.

The complete mitochondrial genome sequence of Platypharodon extremus (Cypriniformes: Cyprinidae).

Platypharodon extremus Herzenstein, 1891 (Cyprinidae: Schizothoracinae), is a monotypic genus species only found in the Qinghai-Tibet plateau of China. Due to human disturbance and related environmental change since the 1950s, the population of P. extremus declined rapidly. As a result, it was listed in the China Red Data Book of Endangered Animal and the China's Protected Species Priority List. There exist very limited researches done on P. extremus. The poor understanding of this species limits the effective protection on this species. Here, we determined the complete mitochondrial DNA sequence of P. extremus. The results show that the mitogenome is 16,651 bp in length, which includes 13 protein-coding genes, 22 tRNA genes, two rRNA genes, and two non-coding regions: control region (D-loop) and origin of light-strand replication (OL). These baseline mitogenomic data provided by this study will facilitate the studies on P. extremus in genetics, developmental biology and conservation biology in the future.

The complete mitochondrial genome of Schizopygopsis chengi baoxingensis (Teleostei, Cyprinidae, Schizopygopsis).

Schizopygopsis chengi baoxingensis is endemic to the Baoxing River in China and may become an endangered species due to its very narrow habitat and the construction of hydropower dams. In this study, we successfully sequenced the first mitochondrial genome of S. c. baoxingensis. The mitogenome is 16,787 bp in length, containing 13 protein-coding genes, two rRNA genes, 22 tRNA genes and a control region (D-loop). The overall base composition of the H-strand is 28.5% A, 26.2% T, 18.4% C, and 26.9% G, with a slight AT bias of 54.7%. The sequenced mtDNA genome of S. c. baoxingensis is similar in gene arrangement to that of other cyprinidaes except for a 191 bp non-coding region found between tRNA(Thr) and tRNA(Pro).

The complete mitochondrial genome sequence of Schizothorax dolichonema (Cypriniformes: Cyprinidae).

The complete mitochondrial genome sequence of Schizothorax dolichonema has been sequenced, which contains 22 tRNA genes, 13 protein-coding genes, 2 rRNA genes and 2 non-coding regions: origin of light-strand replication and control region, with the total length of 16,583 bp. The gene order and composition are similar to most of other vertebrates. Most of the genes are encoded on heavy strand, except for eight tRNA and ND6 genes. The mitogenome sequence of S. dolichonema would contribute for better understanding of biogeography and evolution of Schizothoracine fishes.

The complete mitochondrial genome of Gymnodiptychus pachycheilus (Teleostei, Cyprinidae, Schizothoracinae).

Gymnodiptychus pachycheilus, an endangered cold-water fish belonging to the specialized schizothoracins, is distributed in plateau lakes and the upper reaches of the Yellow and Yangtze Rivers on the northeastern Qinghai-Tibet Plateau in China. In this study, we determined the complete mitogenome sequence of G. pachycheilus. Its complete mitochondrial genome is 16,675 bp in size, and includes 13 protein-coding genes, 22 tRNA genes, 2 rRNA genes and 1 control region, which has identical genomic organization and structure to other vertebrates, with the exception of 86 bp non-coding region between tRNA(Thr) and tRNA(Pro). This new complete mitogenome could provide useful data for further studies on stock evaluation and conservation genetics of this species.