Phylogenetic Position of the Queer, Backward-bent Entoproct Loxosoma axisadversum (Entoprocta: Solitaria: Loxosomatidae)

Abstract

The solitary entoproct Loxosoma axisadversum Konno, 1972 was found on the body surface of the maldanid polychaete Nicomache personata Johnson, 1901 obtained among roots of the seagrass Phyllospadix iwatensis Makino collected at a depth of about 1 m in Oshoro Bay, Hokkaido, Japan. The species had previously been known from elsewhere in northern Japan, attached to another maldanid, Nicomache minor Arwidsson, 1907. The morphology of the new material is briefly described with photographs taken in life. A preliminary phylogenetic analysis using concatenated partial sequences of the mitochondrial cytochrome c oxidase subunit I (COI) gene, as well as the nuclear 18S and 28S rRNA genes, placed L. axisadversum as the sister taxon to all the rest of Solitaria included in the analysis, indicating non-monophyly of the genus Loxosoma Keferstein, 1862.

Molecular Phylogeny of the Family Capitellidae (Annelida)

“…From 42 specimens from which a sequence was obtained for at least one of these markers, 31 were selected to represent putative species (operational taxonomic units, or OTUs) to be included in analyses (Table 1). As outgroup taxa, one individual each of the maldanid Nicomache personata Johnson, 1901 (partially sequenced by Kajihara et al, 2014) and the naidid oligochaete Tubifex tubifex (Müller, 1774) (cultured by Professor Takashi Shimizu, Hokkaido University) were sequenced (Table 1). All specimens not destroyed for DNA extraction have been deposited in the Invertebrate Collection of the Hokkaido University Museum (ICHUM), Sapporo (Table 1).…”