Karyotype of the invasive species Pterois volitans (Scorpaeniformes: Scorpaenidae) from Margarita Island, Venezuela

Abstract

Abstract:The genus Pterois includes nine valid species, native to the Red Sea and Indian Ocean throughout the Western Pacific. P. volitans and P. miles 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 Pterois only cover basic aspects of three species, including P. volitans 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 P. volitans 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 in situ 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 P. volitans are in fact this species, and hence exclude the possibility of a misidentification of P. miles. 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 P. volitans in previous analysis of specimens collected in Indian Ocean (Java), suggesting the occurrence of chromosome microrearrangements involving heterochromatin during the spread of P. volitans. Rev. Biol. Trop. 62 (4): 1365-1373. Epub 2014 December 01.

First cytogenetic analysis of Ichthyoelephas humeralis (Günther, 1860) by conventional and molecular methods with comments on the karyotypic evolution in Prochilodontidae

“…Chromosome preparations were obtained injecting 0.0125% colchicine intraperitoneally (1.0 ml/100 g body weight) 50 min before sacrificing, as described by Nirchio and Oliveira (2006). Before being sacrificed, the specimens received a numbing overdose of Benzocaine (250 mg/L) until the cessation of opercular movements (AVMA 2013).…”

“…Before being sacrificed, the specimens received a numbing overdose of Benzocaine (250 mg/L) until the cessation of opercular movements (AVMA 2013). Mitotic chromosome preparations were obtained by the conventional air-drying method, as described in Nirchio and Oliveira (2006).…”

Near-chromosome level genome assembly of devil firefish, Pterois miles

“…Indeed, between contigs 2, 3, 4, 6 and 7 of devil firefish and chromosomes 16, 10, 11, 18 and 5 of three-spined stickleback, there was high pairwise conservation, respectively. Taking into consideration that the haploid number of P. miles should be the same as its con-generic species, P. volitans, n=24 (Nirchio et al, 2014), an interesting fact arose. This revealed the fusion of coding regions from more than one contigs of P. miles to single chromosomes of G. aculeatus (e.g.…”

Atlantic size record for Pterois volitans (Actinopterygii: Scorpaeniformes: Scorpaenidae) with new morphological data on head spinules

“…The colonization process of the red lionfish, Pterois volitans (Linnaeus, 1758), has been well documented along the Gulf of Mexico and the Caribbean Sea (Chevalier et al 2008, González et al 2009, Morris and Akins 2009, Schofield 2009, 2010, Aguilar-Perera and Tuz-Sulub 2010, Lasso-Alcalá and Posada 2010, Ruttenberg et al 2012, Ferreira et al 2015, Sandel et al 2015. Although cytogenetic, molecular, behavioural, and ecological studies of this species have been made (Cure et al 2012, Nirchio et al 2014, Coronado-Carrascal et al 2015, García-Rodríguez et al 2015, the size ranges reported for this species have not been well documented. The maximum total length of red lionfish reported by Randall et al (1990) was 380 mm TL.…”