New morphological and molecular evidence confirm the presence of the Norwegian skate Dipturus nidarosiensis (Storm, 1881) in the Mediterranean Sea and extend its distribution to the western basin

Abstract

The present study confirms the presence of the Norwegian skate Dipturus nidarosiensis (Storm, 1881) (Stehmann et al., 2015).

The occurrence of Norwegian skate, Dipturus nidarosiensis (Elasmobranchii: Rajiformes: Rajidae), in the Strait of Sicily, central Mediterranean

“…The record of a juvenile male confirmed the occurrence of D. nidarosiensis in the Strait of Sicily previously assumed by Massi et al (2017) on the basis of a record of one egg capsule found off Pantelleria Island. The presence of the species supports the role of ecological corridor of the Strait of Sicily in connecting organisms living in the western basin (Cannas et al 2010, Follesa et al 2012, Ramírez-Amaro et al 2017 with those distributed in the Ionian Sea (Carbonara et al 2019). The Strait of Sicily is also considered a biodiversity hotspot for cartilaginous fish in the Mediterranean Sea (Enajjar et al 2015, Bradai et al 2018, Di Lorenzo et al 2018) and this new species record strengthens the importance of this area for the conservation of this vulnerable group, as has already been stated in previous studies (Lauria et al 2015).…”

“…The Strait of Sicily is also considered a biodiversity hotspot for cartilaginous fish in the Mediterranean Sea (Enajjar et al 2015, Bradai et al 2018, Di Lorenzo et al 2018) and this new species record strengthens the importance of this area for the conservation of this vulnerable group, as has already been stated in previous studies (Lauria et al 2015). In addition, the new record of Norwegian skate in the Strait of Sicily points to a wider Mediterranean distribution than previously thought (Ramírez-Amaro et al 2017). Indeed, in the Mediterranean, this species is one of the deepest living skates with records ranging from 600 up to 1400 m (Cannas et al 2010).…”

“…It was a juvenile male in the maturing phase (stage 2) of 95.6 cm TL and 3466 g. The DnSoS was estimated to be 7 years old, confirming the delayed sexual maturity of the species. The biometrics of the DnSoS, as well as a comparison with specimens reported by Ramírez-Amaro et al (2017), are provided in Table 1. The maturity stage at length of capture was comparable to the specimens recorded by Follesa et al (2012) as well as to the estimated length at first maturity of the species in Atlantic waters (Sulak et al 2009).…”

“…The Norwegian skate, Dipturus nidarosiensis (Storm, 1881), is a benthopelagic species living on the continental slope from 125 m to more than 1400 m depth (Stehmann and Bürkel 1984, Stehmann 1991, Last et al 2016). The species is present mainly in the eastern Atlantic from Iceland, fjords of central and southern Norway, around Rockall, through Ireland to the Northern Mauritania and South Africa (McEachran and Dunn 1998, Compagno 1999, Williams et al 2008, George 2009, Last et al 2016, McEachran and Séret 2016, Weigmann 2016.…”

Peer Review #1 of "On the presence of Dipturus nidarosiensis (Storm, 1881) in the Central Mediterranean area (v0.2)"

“…D. nidarosiensis is one of the species that is often misclassified in both the Atlantic and the Mediterranean Basin (Cannas et al, 2010;Follesa et al, 2011;Cariani et al, 2017;Ramírez-Amaro et al, 2017). The geographical distribution of the Norwegian skate D. nidarosiensis is known to occur along the northeast Atlantic, from Iceland, the Faroe Islands and northern Norway to Madeira and northern Mauritania (Stehmann, 1990).…”