Phylogenetic relationships of Grapsoidea and insights into the higher phylogeny of Brachyuran.

Decapoda is one of the most diverse crustacean orders, and has become an important research subject. However, the phylogenetic relationships among the main lineages of Decapoda remain uncertain, especially in the order Brachyura. Herein, we sequenced the whole mitochondrial genome of V. litterata and constructed a phylogenetic tree to understand its phylogenetic relationships with other species. The results showed that the mitochondrial genome of V. litterata was generally similar to mitogenomes of Metazoa reported in the literature, with a size of 16,247 bp, 37 genes, and a control region. Both AT-skew and GC-skew were negative, indicating more abundant Cs and Ts than Gs and As. The gene arrangement of V. litterata is identical to those of Eriocheir hepuensis, Cyclograpsus granulosus, Hemigrapsus sanguineus, Helicana wuana, and Helice tientsinensis but differs from the pancrustacean ground pattern and typical arrangement of Brachyuran crabs. Phylogenetic reconstruction showed that V. litterata belongs to the Varunidae.