RED SEA BIODIVERSITY Morphological and molecular divergence between Crenidens crenidens (Forsskål, 1775) and C. indicus Day, 1873 (Perciformes: Sparidae) and notes on a Red Sea endemic lineage of C. crenidens Sergey V. Bogorodsky 1,2 & Yukio Iwatsuki 3 & Shabir A. Amir 4,5 & Ahmad O. Mal 6 & Tilman J. Alpermann 1 Received: 13 March 2017 /Revised: 21 June 2017 /Accepted: 28 June 2017 # Senckenberg Gesellschaft für Naturforschung and Springer-Verlag GmbH Germany 2017 Abstract Additional data, resulting from examination of newly collected material from the Red Sea, east coast of Africa, Arabian Gulf, Pakistan, and western coast of India, and a phylogenetic analysis of the COI barcoding region, con- firms Crenidens crenidens (Forsskål) and C. indicus Day as valid species. The latter species was earlier regarded as a sub- species of C. crenidens. In addition, the analyses herein show that specimens from the Red Sea form a distinct monophyletic sub-clade within C. crenidens, characterized by low genetic divergence from specimens from the southwestern Indian Ocean. Close comparison of 34 morphological characters showed that specimens from South Africa and Mozambique differ from Red Sea specimens only in having slightly longer pelvic fins [4.6–4.9 in standard length (SL) vs. 4.8–6.1 in SL]. Examination of additional specimens of both species provided more assessment of inter- and intraspecific variation in meris- tic and morphometric characters. A new set of characters that help to distinguish C. indicus from C. crenidens is proposed: the former species has a deeper body and caudal peduncle; more scales between fifth dorsal-fin spine and lateral line; scales on top of head extending forward to vertical through posterior margin of pupil; longer pelvic fins; lips with tiny cirri; caudal fin blackish distally; and usually with obvious black spot at pectoral-fin axil. Crenidens indicus was previ- ously reported from central Oman, Arabian Gulf, to Pakistan; herein its presence from the western coast of India, Gujarat and Mumbai (= Bombay), is confirmed. Descriptions of C. crenidens and C. indicus based on material examined, pho- tographs of alive and fresh fishes and an updated key to the three known species of Crenidens are provided. Keywords Sparidae . Crenidens . Seabreams . DNA barcoding . Phylogenetic analysis . Geographical distribution Communicated by M. Sonnewald Electronic supplementary material The online version of this article (doi:10.1007/s12526-017-0764-6) contains supplementary material, which is available to authorized users. * Sergey V. Bogorodsky ic187196@yandex.ru Yukio Iwatsuki yuk@cc.miyazaki-u.ac.jp Shabir A. Amir shabiramir@yahoo.com Tilman J. Alpermann Tilman.Alpermann@senckenberg.de 1 Senckenberg Research Institute and Natural History Museum Frankfurt, Senckenberganlage 25, 60325 Frankfurt a.m., Germany 2 Station of Naturalists, Omsk, Russia 3 Department of Marine Biology and Environmental Sciences, University of Miyazaki, 1-1 Gakuen-kibanadai-nishi, Miyazaki 889-2192, Japan 4 Centre of Excellence in Marine Biology, University of Karachi, Karachi, Pakistan 5 Pakistan Museum of Natural History, Garden Avenue, Shakarparian, Islamabad 44000, Pakistan 6 Marine Biology Department, Faculty of Marine Sciences, King Abdulaziz University, Jeddah, Saudi Arabia Mar Biodiv DOI 10.1007/s12526-017-0764-6