Molecular phylogenetic assessment of the subfamily Dendronereidinae Pillai, 1961 (Annelida: Nereididae), with the establishment of Tylorrhynchinae subfam. nov. and the descriptions of two new species from Indonesia

Abstract The status of the subfamily Dendronereidinae has been subject to uncertainty, because its primary defining morphological character (the presence of branchiae) has been shown to be non-homologous. Despite this, Dendronereidinae is currently considered valid but restricted to a single genus, Dendronereis, following the exclusion of Dendronereides and Tambalagamia. However, no genetic data were previously available for Dendronereides, leaving its placement unresolved. In this study, we conduct a phylogenetic assessment using complete mitochondrial genomes and nuclear 18S ribosomal RNA sequence data, providing the first molecular data for Dendronereides and allowing, for the first time based on molecular evidence, an evaluation of Dendronereidinae monophyly as originally proposed. We also describe two new species, Dendronereis javaensis sp. nov. and Dendronereides cilacapensis sp. nov., collected from Central Java, Indonesia. Our phylogenetic analyses confirm a monotypic Dendronereidinae, with Dendronereis as their sole representative, whereas Tambalagamia is placed within Gymnonereidinae. Dendronereides, however, is recovered as the sister taxon to Tylorrhynchus, supporting the establishment of Tylorrhynchinae subfam. nov. to accommodate these two genera.