An ocean yet to be discovered: increasing systematic knowledge of Indo-Pacific Okenia Menke, 1830 (Nudibranchia : Goniodorididae)
Sofía Paz-Sedano A G , Nerida G. Wilson B C , Leila Carmona D , Terrence M. Gosliner E and Marta Pola A FA Departamento de Biología, Facultad de Ciencias, Universidad Autónoma de Madrid, Campus de Excelencia Internacional UAM + CSIC, Madrid, Spain.
B Collections & Research, Western Australian Museum, Welshpool, WA 6106, Australia.
C School of Biological Sciences, University of Western Australia, Perth, WA 6009, Australia.
D Instituto Universitario de Investigación Marina (INMAR), Universidad de Cádiz, Puerto Real, Cádiz, Spain.
E Department of Invertebrate Zoology, California Academy of Sciences, San Francisco, CA 94118, USA.
F Centro de Investigación en Biodiversidad y Cambio Global (CIBC-UAM), Campus de Excelencia Internacional UAM + CSIC, Madrid, Spain.
G Corresponding author. Email: sofia.paz@uam.es
Invertebrate Systematics 35(7) 797-825 https://doi.org/10.1071/IS20088
Submitted: 29 December 2020 Accepted: 22 April 2021 Published: 23 September 2021
Abstract
Numerous faunistic and ecological studies have been conducted throughout the Indo-Pacific Ocean to assess its biodiversity. Despite the abundance of research, studies on the species that inhabit the Indo-Pacific are still necessary due to its extent and high species richness. The major species richness of the genus Okenia Menke, 1830 (Nudibranchia, Goniodorididae) is found in the Indo-Pacific Ocean, including 38 of 60 valid species. Nevertheless, this number does not represent the real biodiversity, since at least 20 more species are already reported in field-guides as undescribed species belonging to this genus. The systematics of the genus Okenia are still unclear since it has been the subject of only a few and incomplete studies. In the present paper, we describe five new Okenia species from the coastlines of Japan, Mozambique and Australia: Okenia aurorapapillata sp. nov., Okenia elisae sp. nov., Okenia nakanoae sp. nov., Okenia siderata sp. nov. and Okenia tenuifibrata sp. nov. Moreover, anatomical details not previously described of Okenia atkinsonorum, Okenia barnardi, Okenia cf. echinata, Okenia hallucigenia, Okenia hiroi, Okenia japonica, Okenia pellucida, Okenia pilosa and Okenia rhinorma are provided. New partial sequences of standard markers (COI, 16S rRNA and H3) were obtained and a phylogenetic analysis that included all species with available data was performed.
ZOOBANK urn:lsid:zoobank.org:pub:28AE2536-A264–4194–8AE3-C430620572E7
Keywords: new species, phylogeny, taxonomy, Japan, Mozambique, Australia.
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