Cryptic species of Nereididae (Annelida : Polychaeta) on Australian coral reefs

Abstract

We investigate the presence of cryptic species among three highly variable nereidid polychaetes commonly found in Australian coral reefs − Nereis denhamensis Augener, 1913, Perinereis suluana (Horst, 1924) and Pseudonereis anomala Gravier, 1901 − based on morphological and molecular data (mitochondrial cytochrome c oxidase subunit I, COI, and nuclear histone H3). DNA extracted and sequenced from 70 specimens from northern Australia and the Philippines indicated the existence of eight species: three matched the types of existing species; four are newly described (Nereis heronensis, sp. nov., N. lizardensis, sp. nov., Perinereis pictilis, sp. nov. and Pseudonereis anomalopsis, sp. nov.) from NE Australia, and one species is described but not named due to lack of material. Nereis denhamensis, N. heronensis, sp. nov. and N. lizardensis, sp. nov. are distinguished from each other by proboscidial paragnath number and morphology of the metamorphosed female. Perinereis suluana can only be separated from P. pictilis, sp. nov. by colour pattern, while Pseudonereis anomala, P. anomalopsis, sp. nov. and P. sp. differ in colour pattern and the number and arrangement of paragnaths. Nereis (Lycoris) tydemani from Maluku, Indonesia, is newly synonymised with P. anomala. Divergence times estimated using COI indicated that speciation in all three groups occurred in the mid Miocene (20–17 ± 7 mya), which corresponds to a period of restricted east–west dispersal as Australia collided with the Indo-Malay archipelago, followed by range expansion opportunities in NE Australia as a result of flourishing coral reefs responding to warming seas and rising sea levels.

A new Notomastus (Annelida, Capitellidae) species from Korean waters, with genetic comparison based on three gene markers

“…Previously known genetic difference of the mtCOI and the 16S rRNA genes among the capitellid species is generally about 18–20% (Jeong et al 2017b, Silva et al 2016). In contrast, the histone H3 gene difference between cryptic nereidid polychaetes is around 2–9% (Glasby et al 2013). Thus, the genetic differences between N. koreanus sp.…”

Complete mitochondrial genome sequence of the giant mud worm Paraleonnates uschakovi Khlebovich & Wu, 1962 (Polychaeta: Nereididae)

“…It is also a source of alkaline protease (Joo et al 2001). Molecular phylogenetic studies have been conducted to solve the taxonomic problem of cryptic nereidid species using mitochondrial partial genes such as COI and 16S (Park & Kim 2007;Tosuji & Sato 2008;Glasby et al 2013). Complete mitochondrial genome sequence can provide more valuable evolutionary information compared to partial genes (Chen et al 2016).…”

Groundwater annelids from Gran Canaria and Fuerteventura (Canary Islands), with the description of two new species of Namanereis (Namanereidinae, Nereididae, Polychaeta)

“…In addition, although part of these differences might be explained by post-mortem contraction in the fixed material, the specimens of N. llanetensis are more robust and have fewer chaetigers than the those of N. canariarum, which are more elongated, filiform in appearance and have greater number of segments. Although both COI and histone H3 data for the two new species have been archived on Genbank, they are, at least partially contaminated, limiting the amount of comparative data available for a molecular analysis of the genus (Glasby et al 2013).…”