TY - JOUR AU - Nirchio, Mauro AU - Eheman, Nicolás AU - Siccha-Ramirez, Raquel AU - Pérez, Julio Eduardo AU - Rossi, Anna Rita AU - Oliveira, Claudio PY - 2014/12/01 Y2 - 2024/03/29 TI - Karyotype of the invasive species Pterois volitans (Scorpaeniformes: Scorpaenidae) from Margarita Island, Venezuela JF - Revista de Biología Tropical JA - Rev. Biol. Trop. VL - 62 IS - 4 SE - AQUATIC VERTEBRATES DO - 10.15517/rbt.v62i4.13029 UR - https://revistas.ucr.ac.cr/index.php/rbt/article/view/13029 SP - 1365–1373 AB - <p>The genus <em>Pterois</em> includes nine valid species, native to the Red Sea and Indian Ocean throughout the Western Pacific. <em>P.</em> <em>volitans</em> and <em>P.</em> <em>miles</em> are native to the Indo-Pacific, and were introduced into Florida waters as a result of aquarium releases, and have been recently recognized as invaders of the Western Atlantic and Caribbean Sea (Costa Rica to Venezuela). Thus far, cytogenetic studies of the genus <em>Pterois</em> only cover basic aspects of three species, including <em>P. volitans</em> from Indo-Pacific Ocean. Considering the lack of more detailed information about cytogenetic characteristics of this invasive species, the objective of the present study was to investigate the basic and molecular cytogenetic characteristics of <em>P. volitans</em> in Venezuela, and compare the results with those from the original distribution area. For this, the karyotypic characteristics of four lionfish caught in Margarita Island, Venezuela, were investigated by examining metaphase chromosomes by Giemsa staining, C-banding, Ag-NOR, and two-colour-Fluorescent <em>in situ</em> hybridization (FISH) for mapping of 18S and 5S ribosomal genes. Comparing the sequences of the 16S gene of the specimens analyzed, with sequences already included in the Genbank, we corroborated that our specimens identified as <em>P. volitans</em> are in fact this species, and hence exclude the possibility of a misidentification of <em>P. miles. </em>The diploid number was 2n=48 (2m+10sm+36a) with FN=60. Chromosomes uniformly decreased in size, making it difficult to clearly identify the homologues except for the only metacentric pair, and the pairs number two, the largest of the submetacentric series. C-banding revealed only three pairs of chromosomes negative for C-band, whereas all remaining chromosomes presented telomeric and some interstitial C-positive blocks. Only two chromosomes were C-banding positive at the pericentromeric regions. Sequential staining revealed Ag-NOR on the tips of the short arms of chromosome pair number two and the FISH assay revealed that 18S rDNA and 5S rDNA genes are co-located on this chromosome pair. The co-localization of 5S rDNA and 45S rDNA is discussed. Both constitutive heterochromatin and NOR location detected in samples examined in this study, differ from those reported for <em>P. volitans</em> in previous analysis of specimens collected in Indian Ocean (Java), suggesting the occurrence of chromosome microrearrangements involving heterochromatin during the spread of <em>P. volitans.</em></p><p><em><br /></em></p><p>Mauro Nirchio<sup>1</sup><strong>*</strong>, Nicolás Eheman<sup>1</sup>,Raquel Siccha-Ramirez<sup>3</sup>, Ernesto Ron<sup>1</sup>,Julio E. Pérez<sup>2</sup> Anna Rita Rossi<sup>4</sup> &amp; Claudio Oliveira<sup>3</sup></p><p align="center"><sup> </sup></p><p><sup>1</sup>Escuela de Ciencias Aplicadas del Mar, Universidad de Oriente, Isla de Margarita, Venezuela; mauro.nirchio@gmail.com</p><p><sup>2</sup>Instituto Oceanográfico de Venezuela, Universidad de Oriente, Cumaná Venezuela; jeperezr@yahoo.com</p><p><sup>3</sup>Departamento de Morfologia, Instituto de Biociências Universidade Estadual Paulista, 18618-970 Botucatu, São Paulo, Brazil; claudio@ibb.unesp.br</p><p><sup>4</sup>Department of Human and Animal Biology, University of Rome “La Sapienza”, via Borelli 50, 00161 Rome, Italy; annarita.rossi@uniroma1.it</p> ER -