Novel diversity in mitochondrial genomes of deep-sea Pennatulacea (Cnidaria: Anthozoa: Octocorallia)

摘要

We present the first documented complete mitogenomes of deep-sea Pennatulacea, representing nine genera and eight families. These include one species each of the deep-sea genera Funiculina, Halipteris, Protoptilum and Distichoptilum, four species eachof Umbellula and Pennatula, three species of Kophobelemnon and two species of Anthoptilum, as well as one species of the epi- and mesobenthic genus Virgularia. Seventeen circular genomes ranged from 18,513 bp [Halipteris cf. finmarchica) to 19,171 bp {Distichoptilum gracile) and contained all genes standard to octocoral mitochondrial genomes (14 protein-coding genes, two ribosomal RNA genes and one transfer RNA). We found at least three different gene orders in Pennatulacea: the ancestral gene order, the gene order found in bamboo corals (Family Isididae), and a novel gene order. The mitogenome of one species of Umbellula has a bipartite genome (~13 kbp and ~5 kbp), with good evidence that both parts are circular.