Three new species of the genus Perinereis (Annelida, Nereididae) from Egyptian coasts

Abstract

Despite being one of the most common groups of polychaetes on intertidal shores, the genus Perinereis (Nereididae) is comparatively poorly known taxonomically, with confusion still existing due to the lack of comprehensive systematic studies. The systematics of Perinereis species from the intertidal Egyptian coasts of the Red Sea, Gulf of Suez and Suez Canal have been investigated using morphology and the mitochondrial barcoding marker cytochrome oxidase subunit I (COI). New sequence data was obtained for 102 Perinereis specimens and analysis included all publicly available COI data from other Perinereis species. The COI data indicate that monophyly of the P. nuntia species group is doubtful, as specimens identified in this species group from south-eastern Asia and Australia form a monophyletic group exclusive of the three new species described in this study from the Red Sea region. A morphometric character set (26 characters) was used to identify and characterize each specimen in the study. Three distinct morphospecies belonging to the P. nuntia species group were found, each differentiated by the number and type of paragnaths on pharyngeal areas V and VI, relative sizes of parapodial lobes, type of notochaetae and neurochaetae, and form of the neurochaetal falciger blades. The three morphospecies were well supported by COI data: two of the three new species, Perinereis suezensissp. nov. and Perinereis fayedensissp. nov., are closely similar to P. nuntia sensu stricto, while the other, Perinereis damiettasp. nov., is similar to P. heterodonta. The new species are described and illustrated, and bring the number of species in Perinereis to 97. The new species are compared and contrasted to the closely similar P. heterodonta, P. nuntia and other congeners from the region.

Two new records and description of a new Perinereis (Annelida, Nereididae) species for the Saudi Arabian Red Sea region

“…Our specimens initially identified as belonging to the P. nuntia complex revealed at least two different morphotypes, which after further morphological (mainly based on paragnath patterns, Fig. 1C, D ) and molecular review corresponded to the new species recently described by Elgetany et al (2022) for the neighbouring Egyptian coast (Suez Canal), namely P. damietta (Fig. 1C ) and P. suezensis (Fig.…”

“…Bootstrap values lower than 80% not displayed B Red Sea MOTU distribution; each coloured pie corresponds to a unique species and respective abundance proportion; larger pie charts indicate higher number of sympatric species. Species from the Suez Canal based on mined GenBank sequences from Elgetany et al (2022) ; abundance proportion based on type material C Perinereis damietta , focus on prostomium and pharynx, dorsal view, specimen NTNU-VM -86031 D Perinereis suezensis , focus on prostomium and pharynx, dorsal view, specimen NTNU-VM -86032 E Perinereis kaustiana sp. nov., focus on prostomium and pharynx, dorsal view, specimen NTNU-VM -86011.…”

“…1B ). Perinereis damietta (which is morphologically more similar to P. heterodonta Gravier, 1899 than to P. nuntia according to Elgetany et al (2022) ), was found mainly in lagoon-like environments, whereas P. suezensis only in fully marine areas. Perinereis kaustiana sp.…”

“…Based on genetic databases (i.e., BOLD and GenBank), and despite the recent advances in integrative studies focused on polychaetes (i.e., Nygren et al 2010 ; Villalobos-Guerrero et al 2021 ; Teixeira et al 2023 ), there are still many taxonomic ambiguities and unidentified annelid species in some groups of Nereididae (i.e., Martin et al 2021 ; Elgetany et al 2022 ). Perinereis Kinberg, 1865 is one of the most diverse genera in this family, currently including between 97 ( Wilson et al 2023 ) to 106 ( WoRMS Editorial Board 2024 ) valid species distributed worldwide.…”

“…The Egyptian side of the Red Sea has been the focus of an increasing amount of polychaete studies either reviewing existing species groups (i.e., Villalobos-Guerrero 2019 ) or describing new species that were previously considered cryptic (i.e., Elgetany et al 2022 ). The northern Saudi Arabian Red Sea and Gulf of Aqaba, despite being expected to host a large biodiversity ( Roberts et al 2002 ; DiBattista et al 2016 ), has seen comparatively few biodiversity studies involving molecular techniques, particularly for polychaetes.…”