Citation: Giovos, I.; Aga-Spyridopoulou, R.N.; Serena, F.; Soldo, A.; Barash, A.; Doumpas, N.; Gkafas, G.A.; Katsada, D.; Katselis, G.; Kleitou, P.; et al. An Updated Greek National Checklist of Chondrichthyans. Fishes 2022, 7, 199. https://doi.org/10.3390/ fishes7040199 Academic Editor: Gioele Capillo Received: 25 June 2022 Accepted: 4 August 2022 Published: 9 August 2022 Publisher’s Note: MDPI stays neutral with regard to jurisdictional claims in published maps and institutional affil- iations. Copyright: © 2022 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https:// creativecommons.org/licenses/by/ 4.0/). fishes Article An Updated Greek National Checklist of Chondrichthyans Ioannis Giovos 1,2,† , Roxani Naasan Aga-Spyridopoulou 1,† , Fabrizio Serena 3,† , Alen Soldo 4,† , Adi Barash 5 , Nikolaos Doumpas 1 , Georgios A. Gkafas 6 , Dimitra Katsada 1 , George Katselis 2 , Periklis Kleitou 7 , Vasileios Minasidis 1,2 , Yannis P. Papastamatiou 8 , Eleana Touloupaki 9 and Dimitrios K. Moutopoulos 2, * ,† 1 iSea, Environmental Organisation for the Preservation of the Aquatic Ecosystems, 54645 Thessaloniki, Greece 2 Department of Animal Production, Fisheries & Aquaculture, University of Patras, 30200 Mesolongi, Greece 3 Institute for Marine Biological Resources and Biotechnology, National Research Council (CNR-IRBIM), I-91026 Mazara del Vallo, Italy 4 Department of Marine Studies, University of Split, 21000 Split, Croatia 5 Sharks in Israel, NGO for the Conservation of Sharks and Rays, Amirim 1214000, Israel 6 Department of Ichthyology and Aquatic Environment, School of Agricultural Sciences, University of Thessaly, 38446 Volos, Greece 7 Marine and Environmental Research (MER) Lab, Limassol 4533, Cyprus 8 Institute of the Environment, Department of Biological Sciences, Florida International University, North Miami, FL 33181, USA 9 MEDASSET-Mediterranean Association to Save the Sea Turtles, 10672 Athens, Greece * Correspondence: dmoutopo@upatras.gr † These authors contributed equally to this work. Abstract: Accurate checklists of species are essential for evaluating their conservation status and for understanding more about their distribution, biology and ecology and, therefore, the first step in order to effectively protect them. According to the existing literature, the Greek seas are rich in chondrichthyan biodiversity and herein, we update the most recent chondrichthyan checklist for the country regarding the species that are present in the Greek waters, correct unvalidated miscellaneous sightings and observations and provide guidelines about future research to improve their conservation. In total, 330 sources were collected from which 276 were used for further analysis, resulting in 1485 records of 67 species, among which 61 are confirmed by experts, including 34 sharks, 26 batoids and one chimaera. We are further listing six species as “Questionable/Not Confirmed”. Keywords: elasmobranchs; batoid; shark; chimaera; Eastern Mediterranean; Aegean Sea; Ionian Sea; Crete 1. Introduction Chondrichthyans are a taxonomic group that contains about 1296 species world- wide [1]. The chondrichthyans belong to two subclasses, Holocephali (Chimaeras) and Elasmobranchii (sharks and batoids). These organisms have been living on earth for about 400 million years. In their majority, they are meso- to upper-level predators in marine ecosystems and may play an important ecosystem role. The Mediterranean Sea, despite its small acreage, is an important area for chondrichthyans, as it is characterized by moderate biodiversity [1], with 88 species already recorded at present [2]. Unfortunately, at the same time, it is probably the most impacted area for chondrichthyans, as they are the most threatened fish group. Particularly, from the 73 species populations in the Mediterranean Sea, which are assessed by the Red List of Threatened Species of the International Union for Conservation of Nature (IUCN), a percentage of 53.4% has been classified as Threatened and more than one-third as Data Deficient or Not Evaluated due to a lack of relevant data [3]. Fishes 2022, 7, 199. https://doi.org/10.3390/fishes7040199 https://www.mdpi.com/journal/fishes