A discovery of great scientific relevance that linked to the birth of “Ispera”, a female specimen of dogfish shark (Mustelus mustelus) which last May saw the light for the first time at the Cala Gonone aquarium in Dorgali.
As confirmed today by the Experimental Zooprophylactic Institute of Piedmont, Liguria and Valle d'Aosta (IZSPLV), which has completed the genetic analyzes on biological samples, the birth would have occurred by parthenogenesis, and therefore without fertilization by male specimens.
It is the first case in the world of scientifically documented virginal reproduction in this species.
Ispera was born in the large pelagic tank (300,000 liters) of the Aquarium of Cala Gonone, which in addition to groupers, amberjacks and many other Mediterranean species has hosted two adult female dogfish for about 10 years.
To confirm parthenogenesis and to define with certainty from which of the two females Ispera was born, specific "microsatellite markers" were used for this species.
In 2020 there was another birth of a female shark, which unfortunately did not survive, but of which biological material had been preserved.
Also in this case, reproduction by parthenogenesis has been confirmed.
The extraordinary news, among other things, is that it was not Ispera's mother who gave birth to this "baby", but the other adult female housed in the pelagic tank.
The birth of "Ispera" is also excellent news because the species, due to overfishing, is at serious risk of extinction, so much so that it has been included in the red list of the International Union for the Conservation of Nature (IUCN) as vulnerable species.
To date, Ispera weighs about 1200 grams and measures 45 cm. It is housed in one of the curatorial tanks of the Cala Gonone Aquarium, where it feeds regularly following a diet based on shrimp, squid and small fish, and seems to be in excellent health.
Mustelus mustelus is a shark from the Triakidae family, commonly known as dogfish. Widespread in the Atlantic Ocean and in the Mediterranean Sea, it is not dangerous for humans, it can reach the maximum size of 2 meters and 24 years of age.
(Unioneonline / vl)
