Abstract
Phascolosoma is one of the most important genera of Sipuncula, many species of which including P. scolops are economic important species in the fishery of southeast China. However, the synonym and misidentification of species in Phascolosoma have been reported repeatedly. Here, we report the complete mitochondrial genome sequence of P. scolops. The mitogenome has 15,515 base pairs and made up of total of 38 genes (13 protein-coding, 23 transfer RNAs and 2 ribosomal RNAs), and a putative control region. The complete mitogenomes of P. scolops will contribute to further phylogenetic and taxonomic study in the genus Phascolosoma.
Sipunculans (known as peanut worms) are an ancient group of exclusively marine benthonic animals which contain about 150 species with a global distribution and a fossil record of dates back to the Early Cambrian (Lemer et al. Citation2015). Phascolosoma is one of the most important genera of Sipuncula, many species of which are economically important due to valuable nutrition of delicious seafood and valuable ingredients of traditional medicines. However, the synonym and misidentification of species in Phascolosoma have been reported repeatedly (Cutler and Cutler Citation1983). Mitochondrial genome is an excellent molecular marker for taxonomy identification and phylogenetic analysis, but adequate mitogenome information about the genus Phascolosoma is still limited (Zhong et al. Citation2020). Here, we report the complete mitochondrial genome sequence of Phascolosoma scolops, which will provide a better insight into taxonomic classification and phylogenetic relationship of Phascolosoma.
The tissue samples of P. scolops from 3 individuals was collected from Beibu Bay, China (Beihai, 21.046257 N, 109.155277E), and the whole body specimens (#GG0083) were deposited at Marine biological Herbarium, Guangxi Institute of Oceanology, Beihai, China. The total genomic DNA was extracted from the muscle of the specimens using an SQ Tissue DNA Kit (OMEGA, Guangzhou, China) following the manufacturer’s protocol. DNA libraries (350 bp insert) were constructed with the TruSeq NanoTM kit (Illumina, San Diego, CA) and were sequenced (2 × 150bp paired-end) using HiSeq platform at Novogene Company, China. Mitogenome assembly was performed by MITObim (Hahn et al. Citation2013). The complete mitogenome of Phascolosoma similis (GenBank accession number: MN813482) was chosen as the initial reference sequence for MITObim assembly. Gene annotation was performed by MITOS (http://mitos2.bioinf.uni-leipzig.de/).
The complete mitogenome of P. scolops from Beibu Bay was found to be 15,515 bp in length (GenBank accession number: MT239480), including the usual set of gene for mitogenome except for extra threonine tRNA which consisting of 13 protein-coding, 23 tRNA and 2 rRNA genes, and a putative control region. The overall base composition of the mitogenome was estimated to be A 32.3%, T 33.1%, C 21.6% and G 13.0%, with a high A + T content of 65.4%, which is slightly higher than Phascolosoma similis (63.5%) (Zhong et al. Citation2020). The mitogenomic phylogenetic analyses showed that P. scolops was first clustered with P. esculenta and then with P. similis in the genus Phascolosoma clade (), which indicated the close relationship between P. scolops and P. esculenta. The taxonomic classification of Phascolosoma using morphological characteristics (Li Citation1989) was consistent with our phylogenetic analyses, which will contribute to further phylogenetic and taxonomic study in the genus Phascolosoma.
Disclosure statement
The authors declare that they have no conflict of interest.
Data availability
The data that support the findings of this study are openly available in [National Center for Biotechnology Information] at [https://www.ncbi.nlm.nih.gov/nuccore], reference number [MT239480].
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References
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