TECHNICAL NOTE Identification of guitarfish species Rhinobatos percellens, R. horkelli, and Zapteryx brevirostris (Chondrichthyes) using mitochondrial genes and RFLP technique T. C. Mariguela Æ B. De-Franco Æ T. V. V. Almeida Æ F. F. Mendonc ¸a Æ O. B. F. Gadig Æ F. Foresti Æ C. Oliveira Received: 24 August 2009 / Accepted: 27 August 2009 / Published online: 11 September 2009 Ó Springer Science+Business Media B.V. 2009 Abstract The RFLP represents a fast and non-expensive tool to access species identification and can be used by fishery and law enforcement authorities to gather data from legal and illegal ray fisheries. In the present study, partial sequences of 16S and COI mitochondrial genes were submitted to RFLP analysis and the results showed that there is a high interspecific variability and no intraspecific polymorphism, making them an useful marker for guitar- fish identification. All samples of Rhinobatidae: Rhinoba- tos percellens, R. horkelli, and Zapteryx brevirostris were positively identified. The main contribution of these forensic identification techniques is the possibility of evaluating population genetics of species status in order to improve conservation plans involving these species. Keywords Conservation genetics Á Mitochondrial genes Á Commercial species Á Rays Á Species identification Introduction The family Rhinobatidae, (guitarfishes) includes the genera Aptychotrema, Trygonorhina, Rhinobatos, and Zapteryx (Compagno 1999). Two genera, Rhinobatos and Zapteryx, and three species, R. percellens (Walbaum 1792), R. horkelli Mu ¨ller and Henle 1841, and Zapteryx brevirostris (Mu ¨ller and Henle 1841) are present in the coastal area of Brazil. Most elasmobranches have slow growth rate, late maturity, and low fecundity when compared to bony fishes (Camhi et al. 1998). These attributes result in very low rates of increase (Smith et al. 1998) and very low resilience to fishing mortality (Hoenig and Gruber 1990). There is increasing evidence that fishing exploitation affects the composition and biodiversity of this group and the impact of fishing on sharks and rays stocks around the world is currently the focus of considerable international interest (Stevens et al. 2000). According to capture records, the population of rays of the genus Rhinobatos has decreased nearly 85% in the extreme South of Brazil between 1985 and 1997 (Miranda and Vooren 2003). Despite the fact that these species, particularly R. hork- elli, face a serious risk of extinction, government measures to protect the rays, such as an immediate ban on their fishing and sale, have not yet been implemented. Unfortunately, one of the major impediments to quantifying the captured fish of each species is the inefficiency in the morphological identification of individuals. According to some studies, only starting from the year 2001, reports on elasmobranches fishing have begun to contain numbers relating to guitarfish (FAO 2006). Even so, the actual classification does not distinguish species but groups of species R. horkelli, R. percellens, and Z. brevirostris, due to their morphologic similarities and the manner in which these fish are pro- cessed in the fishing boats, thus precluding morphological identification and recognition of each species. Due to the simplicity and cost of RFLP technique using mitochondrial genes, we propose a RFLP protocol for secure differentiation among R. horkelli, R. percellens, and Z. brevirostris. This protocol may be applicable to the T. C. Mariguela (&) Á B. De-Franco Á F. F. Mendonc ¸a Á F. Foresti Á C. Oliveira Laborato ´rio de Biologia e Gene ´tica de Peixes, Departamento de Morfologia, Instituto de Biocie ˆncias, Universidade Estadual Paulista, Botucatu, SP 186018-000, Brazil e-mail: tatimariguela@gmail.com T. V. V. Almeida Á O. B. F. Gadig Campus Litoral Paulista, UNESP – Universidade Estadual Paulista, Sa ˜o Vicente, SP, Brazil 123 Conservation Genet Resour (2009) 1:393–396 DOI 10.1007/s12686-009-9091-y