Timareteposteria, a new cirratulid species from Korea (Annelida, Polychaeta, Cirratulidae).

Hyun Ki Choi,Hana Kim,Seong Myeong Yoon

doi:10.3897/zookeys.806.27436

Abstract

A new cirratulid species, Timareteposteriasp. n., is described from the intertidal habitats of the eastern coast of South Korea. The new species is closely related to Timareteluxuriosa (Moore, 1904) from southern California based on morphological similarity of the branchial and tentacular finalents and the noto- and neuropodial spines. However, T.posteriasp. n. differs from the latter based on the following characteristics: 1) evenly divided peristomium into three annulations; 2) 2–4 neuropodial spines originating in the posterior chaetigers alternated by a few capillaries; and 3) complete shift in branchial finalents located about one-third between the notopodium and the dorsal midline. The new species has a methyl green staining pattern (MGSP) distinct from other Timarete species. Detailed description and illustrations of the new species are provided with molecular information based on the partial sequences of the mitochondrial cytochrome c oxidase subunit I (COI) and 16S ribosomal RNA (16S). This study also includes a key and discussion of known Timarete species from East Asia.

Highlights

The genus Timarete Kinberg, 1866 is a typical multi-tentaculate genus assigned to the cirratulid polychaetes (Blake 1996)
T. posteria sp. n. differs from the latter based on the following characteristics: 1) evenly divided peristomium into three annulations; 2) 2–4 neuropodial spines originating in the posterior chaetigers alternated by a few capillaries; and 3) complete shift in branchial filaments located about one-third between the notopodium and the dorsal midline
We examined the molecular phylogenetic relationship based on the Maximum likelihood (ML) tree using the genetic data available from GenBank on several cirratulids belonging to the multi-tentaculate genera, Cirriformia, Cirratulus, and Timarete, with the new species (Rousset et al 2007, Hardy et al 2011, Magalhães et al 2014, Weidhase et al 2014, Lado et al 2016, Weidhase et al 2016)

Summary

Introduction

The genus Timarete Kinberg, 1866 is a typical multi-tentaculate genus assigned to the cirratulid polychaetes (Blake 1996). Several species belonging to Timarete have been taxonomically re-evaluated (Blake 1996, Çinar 2007, Magalhães and Bailey-Brock 2010, Magalhães et al 2014). Magalhães et al (2014) re-examined several multitentaculate cirratulid species collected from the Brazilian coast including four Timarete species: T. caribous (Grube & Ørsted in Grube, 1859), T. ceciliae Magalhães, Seixas, Paiva, & Elias, 2014, T. oculata (Treadwell, 1932), and T. punctata species complex. We conducted a detailed examination of this species using methyl green staining pattern (MGSP) and several ontogenetic characters including the segmental origins of tentacular filaments, distributions of the neuroacicular and notoacicular spines, and dorsal shift of branchial filaments as used by previous investigators (Çinar 2007, Magalhães and BaileyBrock 2010, Magalhães et al 2014). We reviewed and discussed Timarete species recorded from East Asia

Materials and methods

Discussion