Comparative Mitochondrial Genome Analyses of Sesarmid and Other Brachyuran Crabs Reveal Gene Rearrangements and Phylogeny

Abstract

Mitochondrial genomes (mitogenomes) are important for understanding molecular evolution and phylogenetic relationships. The complete mitogenome of Perisesarma bidens was determined, which is 15,641 bp in length. The A + T content of P. bidens mitogenome was 74.81%. The AT skew was slightly negative (−0.021). The 22 tRNAs ranged from 65 to 73 bp and were highly A + T biased. All tRNA genes had typical cloverleaf structures, except for the trnS1 gene, which lacked a dihydrouridine (DHU) arm. The gene order within the P. bidens mitogenome was identical to the pancrustacean ground pattern, except for the translocation of the trnH. Additionally, the gene order of trnI-trnQ-trnM in pancrustacean ground pattern became trnQ-trnI-trnM in P. bidens. Phylogenetic analyses supported the inclusion of P. bidens in Sesarmidae and the promotion of Sesarminae to Sesarmidae. The results will help us to better understand the status and evolutionary history of Grapsoidea crabs.

Gene Arrangement and Adaptive Evolution in the Mitochondrial Genomes of Terrestrial Sesarmid Crabs Geosesarma faustum and Geosesarma penangensis

“…All Sesarmidae species cluster into a clade consisting of two sister groups, which was consistent with previous findings (Wang et al, 2019;Li et al, 2020;Lu et al, 2020; Sesarmidae species are most closely related to Gecacinidae, constituting part of the Grapsoidea group, which is in accordance with the results of the studies by Chen et al (2019), Wang et al (2019), Lu et al (2020), and. The mitochondrial phylogenomic analyses including our dataset have shown the divergent phylogenetic status of Grapsidae and Dotilidae (Wang et al, 2019;Li et al, 2020;. In the ML tree, Grapsidae and Dotilidae form a sister group and constitute the base of the (((((Sesarmidae) + Gecarcinidae) + Xenograpsidae) + Ocypodidae) + (Varunidae + (Macropthalmidae + Mictyridae))) clade.…”

“…This result confirmed that Geosesarma belongs to Grapsoidea, Sesarmidae, congruent with the morphological assignments (Ng et al, 2008;Ng, 2017;Ng and Wowor, 2019;Shy and Ng, 2019). All Sesarmidae species cluster into a clade consisting of two sister groups, which was consistent with previous findings (Wang et al, 2019;Li et al, 2020;Lu et al, 2020; Sesarmidae species are most closely related to Gecacinidae, constituting part of the Grapsoidea group, which is in accordance with the results of the studies by Chen et al (2019), Wang et al (2019), Lu et al (2020), and. The mitochondrial phylogenomic analyses including our dataset have shown the divergent phylogenetic status of Grapsidae and Dotilidae (Wang et al, 2019;Li et al, 2020;.…”

“…The trnS also lacks the thymidine-pseudouridine-cytidine (T C) stem and loop, whereas trnC (G. penangensis) has reduced the DHU stem. Aberrant tRNA structures in mitogenomes appear to be a common phenomenon in many species (Li et al, 2020;; previous research on nematodes and metazoans suggests that such features have no effect on tRNA function (Watanabe et al, 2014;Fourdrilis et al, 2018).…”

Complete Mitochondrial Genome of Phoneutria Boliviensis (Araneae, Ctenidae): New Insights Into the Phylogeny and Evolution of Spider

“…The animal mitochondrial genome (mitogenome) has been widely used for the reconstruction of phylogenetic relationships at several taxonomic levels due to its rich signals from sequence information and gene arrangement, from populations to phyla, and has been widely used for the resolution of taxonomic controversies [7][8][9] . The arthropod mitochondrial genome is a compact circular molecule of usually 14-19 kb in size, with 37 genes (13 protein-coding genes, 22 tRNA genes, two rRNA genes), and a noncoding D-loop region.…”

“…These spiders are essentially wandering, nocturnal spiders and represent one of the main groups of medically important spiders in South America because of their defensive behavior, synanthropic habits, potent venom, and wide range of prey, including both invertebrates and vertebrates 5,6 . The animal mitochondrial genome (mitogenome) has been widely used for the reconstruction of phylogenetic relationships at several taxonomic levels due to its rich signals from sequence information and gene arrangement, from populations to phyla, and has been widely used for the resolution of taxonomic controversies [7][8][9] . The arthropod mitochondrial genome is a compact circular molecule of usually 14-19 kb in size, with 37 genes (13 protein-coding genes, 22 tRNA genes, two rRNA genes), and a noncoding D-loop region.…”