Seven new species of Tetranemertes Chernyshev, 1992 (Monostilifera, Hoplonemertea, Nemertea) from the Caribbean Sea, western Pacific, and Arabian Sea, and revision of the genus

By

Cherneva, Irina
Ellison, Christina
Zattara, Eduardo E
Norenburg, Jon
Schwartz, Megan
Junoy, Juan
Maslakova, Svetlana

Type

Article

Date of Publication

2023

Original Publication

ZooKeys

Volume

1181

Pages

167--200

Subjects

Belize , Description , histology-free , Nemertea , Oman , Panama , revision , ribbon worm

Contributed by

Pensoft Publishers

Language

English

Published by

Sofia, Bulgaria Pensoft Publishers

Identifiers

DOI: https://doi.org/10.3897/zookeys.1181.109521

 

Abstract

The marine ribbon worm genus Tetranemertes Chernyshev, 1992 currently includes three species: the type species T. antonina (Quatrefages, 1846) from the Mediterranean Sea, T. rubrolineata (Kirsteuer, 1965) from Madagascar, and T. hermaphroditica (Gibson, 1982) from Australia. Seven new species are described: T. bifrostsp. nov., T. ocelatasp. nov., T. majinbuuisp. nov., and T. pastafariensissp. nov. from the Caribbean Sea (Panamá), and three species, T. unistriatasp. nov., T. paulayisp. nov., and T. arabicasp. nov., from the Indo-West Pacific (Japan and Oman). As a result, an amended morphological diagnosis of the genus is offered. To improve nomenclatural stability, a neotype of Tetranemertes antonina is designated from the Mediterranean. The newly described species, each characterized by features of external appearance and stylet apparatus, as well as by DNA-barcodes, form a well-supported clade with T. antonina on a molecular phylogeny of monostiliferan hoplonemerteans based on partial sequences of COI, 16S rRNA, 18S rRNA, and 28S rRNA. Six of the seven newly described species, as well as T. rubrolineata, possess the unusual character of having a central stylet basis slightly bilobed to deeply forked posteriorly in fully grown individuals, a possible morphological synapomorphy of the genus. In addition, an undescribed species of Tetranemertes is reported from the Eastern Tropical Pacific (Panamá), increasing the total number of known species in the genus to eleven.