Spiny Butterfly Ray

• The IUCN listed it in 2021 as Endangered globally and Critically Endangered in Europe and the Mediterranean, because of the decline of its populations under fishing pressure and habitat destruction.
• It is ovoviviparous: the embryos develop inside the mother, feeding first on the yolk and then on a uterine secretion, and are born fully formed after about six months.
• It is told apart from the smooth butterfly ray by the spine at the base of the tail and by a small fleshy appendage on the edge of each spiracle.
• Its disc is roughly twice as wide as it is long, a silhouette it shares with no other ray in the Mediterranean.
• It is told apart from the smooth butterfly ray by the sting at the base of its tail and by a small tentacle-like appendage on the rim of each spiracle.
• In the Mediterranean its decline exceeds 80% over two decades, and it was thought to have vanished from the Adriatic: there were no modern records until a gravid female turned up in Albania in 2022, the first documented case in the northern Mediterranean.
• Between 2022 and 2023 five more records were added in Albania and Croatia, which has reopened conservation work in the area.
• Old specimens reached 400 cm in disc width; those caught in the Mediterranean today rarely exceed 110.

Skeleton type

Vertebrate - cartilaginous skeleton (chondrichthyan)

Habitat and environment

Sandy and muddy bottoms of warm coastal waters of the Atlantic, the Mediterranean and the Black Sea

Gestation / incubation

About 6 months of gestation

Litter / clutch size

From 2 to 7 young per litter

Sources consulted: Wikipedia (es): Gymnura altavela