butterfly ray

Spiny butterfly rays are ovoviviparous and give birth to live young.

Spiny butterfly rays are harmless to humans, though if stepped on its tail spine can cause a painful wound.

Family Gymnuridae (butterfly rays)

Potential predators of spiny butterfly rays include larger fish such as the great hammerhead (Sphyrna mokarran), and marine mammals.

The butterfly rays are a group of rays forming the genus Gymnura and the family Gymnuridae.

Its length is about equal to the distance between the snout tip and the vent, distinguishing this species from other butterfly rays that have shorter tails.

Like other butterfly rays, this species is viviparous with the young sustained initially by yolk, and later by histotroph ("uterine milk") produced by the mother.

As the name Gymnura was already in use, referring to the butterfly rays, later that year Müller and Henle replaced it with Urogymnus.

The body of butterfly rays is flattened and surrounded by an extremely broad disc formed by the pectoral fins, which merge in front of the head.

Further research is needed to determine whether the isolated longtail butterfly rays in French Polynesia are in fact the same species as those from the rest of its range.

This behavior likely serves to stun the prey before capture, as the pectoral fins of butterfly rays contain a high proportion of red muscle and can deliver blows of substantial force.

McEachran et al. place the butterfly rays in the subfamily Gymnurinae of the family Dasyatidae, but this article follows FishBase and ITIS in treating them as a family.