New record of Squalus cubensis Howell Rivero, 1936 (Chondrichthyes, Squalidae) in Colombia

Univ. Sci. 21 (2): 159-166, 2016. doi: 10.11144/Javeriana.SC21-2.nros Bogotá original article New record of Squalus cubensis Howell Rivero, 1936 (Chondrichthyes, Squalidae) in Colombia Diana María Orozco-Velásquez1, *, Fabio Gómez-Delgado1 Edited by Juan Carlos Salcedo-Reyes () 1. Pontificia Universidad Javeriana. Unidad de Ecología y Sistemática UNESIS. Departamento de Biología. Facultad de Ciencias. Pontificia Universidad Javeriana, Bogotá D.C. Colombia. * Abstract Two Cuban dogfish Squalus cubensis (Squalidae) are recorded for the first time in the area of influence of Isla Fuerte, an island located at the limit of the southern continental shelf of the Colombian Caribbean. Additionally, it is the first capture report of this species in Colombia by artisanal fishery and at shallower catch depths than those reported in previous records. Due to the little existing knowledge about the biology of this species in the country, information on the reproductive biology of the captured individuals is provided. Received: 07-05-2015 Accepted: 31-05-2016 Published on line: 17-06-2016 Keywords: Squalus cubensis; Shark; Squalidae; Cuban dogfish; Isla Fuerte. Citation: Orozco-Velásquez DM, Gómez-Delgado F. New record of Squalus cubensis Howell Rivero, 1936 (Chondrichthyes, Squalidae) in Colombia, Universitas Scientiarum, 21 (2): 159-166, 2016. doi: 10.11144/Javeriana.SC21-2.nros Introduction Funding: Shark Research Group of the Pontificia Universidad Javeriana. Electronic supplementary material: N/A The Cuban dogfish Squalus cubensis (Howell Rivero, 1936) inhabits the subtropical Atlantic Ocean from North Carolina to southern Brazil and Argentina, including the greater Caribbean and the Gulf of Mexico (Compagno, 1984, 2002; Monzini, 2006; Jones et al., 2013; Brooks et al., 2015). Schools are probably present below 100 m in the Portobelo area (Panama, Caribbean Coast, Colon Province) and in the San Andres archipelago area (Monzini, 2006). The Cuban dogfish is a bottom-dwelling species that inhabits deep warm temperate and tropical waters of the outer continental shelf and uppermost slopes, and is found on or near the bottom in large dense schools. Reported capture depths vary between 60 and 730.6 m (Compagno, 1984; Castro, 2011; Jones et al., 2013, Brooks et al., 2015). This species may form large schools of same-sex and size individuals (Castro, 2011) and is never found in surface waters. Juvenile Cuban dogfishes reside in shallow waters along the continental shelf and mature specimens are found in deep waters (Compagno 1984, 2002). Little information is known about this species and separate catch statistics are not reported for any population. Information available refers to S. cubensis as by-catch of artisanal and commercial fisheries in the Caribbean, mainly caught in the northern Gulf of Mexico, although details are lacking and this species cannot be assessed beyond Data Deficient (IUCN Red List) at present (Monzini, 2006). Universitas Scientiarum, Journal of the Faculty of Sciences, Pontificia Universidad Javeriana, is licensed under the Creative Commons Attribution 4.0 International Public License 160 New record of Squalus cubensis Fig. 1. Geographic location of the site of capture of Squalus cubensis off Isla Fuerte, Colombia. Previous records have reported the presence of the Cuban dogfish in Colombia only through industrial fishery studies and experimental trawl surveys (Rey-Carrasco & Acero (1988) in the continental slope of the northeastern coast; Puentes et al. (2009) in the San Andrés archipelago; and Paramo et al. (2012, 2015) across the Colombian Caribbean. The present article describes two females captured in the southern continental shelf of the Colombian Caribbean (Figure 1), becoming the first record of this species in the area. Furthermore, some characteristics of its reproduction are described in order to provide additional information to the basic knowledge of the species. The recording of morphometric measures was made point-to-point on the fresh specimens, using a measuring tape and a caliper, following Compagno (1984, 2001, and 2002). For pregnant females, number of embryos in utero and their sex, location (left or right uterus), and total length of each embryo (LTE) were recorded (Braccini et al., 2006). The specimens were preserved in 5% formaldehyde, transferred to 70% alcohol and deposited under the catalog number MPUJ 7875 in the Museum of Natural History of the Pontificia Universidad Javeriana, in Bogotá-Colombia. Results and discussion Squaliformes Compagno, 1973 Squalidae Blainville, 1816 Squalus Linnaeus, 1758 Squalus cubensis Howell Rivero, 1936. Proc.Boston Soc.Nat.Hist., 41(4): 45, pls.10 and 11 (Figure 2). Universitas Scientiarum Vol. 21 (2): 159-166 http://ciencias.javeriana.edu.co/investigacion/universitas-scientiarum 161 Orozco-Velásquez & Gómez-Delgado Fig. 2. Female of Squalus cubensis 51.7 cm LT. a. Side view. b. Ventral view of the head. c. Detail of the eye and spiracle. d. Detail of the upper teeth. e. First dorsal fin. f. Second dorsal fin. g. Caudal fin. On 25 September 2014, two adult females (MPUJ 7875) were captured by artisanal fishermen through longline fishing in the limit of the southern continental shelf of the Colombian Caribbean, 27 km off Isla Fuerte and 40 km off the continental coastline at 100 meters depth, at the fishing locality named El Risco (9° 26’ 25. 72’’ N, 76° 25’ 55. 82’’ W). The record of these two females constitutes the first report of this species in the southern continental shelf, extending its distribution range to the southern Caribbean Sea. Table 1 shows the morphological measurements taken on both specimens. The total length (51.7 and 50 cm LT) is larger than previous records in Colombian waters: 29.5 cm LT northeastern coast of Colombia (Rey-Carrasco & Acero 1988). Currently, there is no additional information about the size of S. cubensis in Colombia. For other locations in the Caribbean (Jamaica, Bahamas, Gulf of Mexico and Venezuela) the size ranges vary between 21.2 and 80 cm LT (McLaughlin & Morrissey, 2004; Jones et al., 2013; Tagliafico et al., 2014; Brooks et al., 2015). In Colombia, the Cuban dogfish has been reported in depth ranges of 270-630 m (Rey-Carrasco & Acero, 1988) and 246-388 m (Paramo et al. 2012, 2015). Other records in the Caribbean show depth ranges between 198.11 and 913 m (McLaughlin & Morrissey, 2004; Jones et al., 2013; Brooks et al., 2015). Our report constitutes the shallowest depth record for this species in the area: 100 m depth. According to Brooks et al. (2015), the variation in depth is attributable to geographical variation in thermal profiles of the water column; they suggest that S. cubensis select vertical habitats based on thermal rather than barometric or photic preferences leading to the disparate depth ranges in different latitudes. Universitas Scientiarum Vol. 21 (2): 159-166 http://ciencias.javeriana.edu.co/investigacion/universitas (...truncated)