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Angelshark (Squatina squatina)

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Arts and crafts time with angelsharks... (Image Credit: Ben Young Landis/CC-BY)

Arts and crafts time with angelsharks… (Image Credit: Ben Young Landis/CC-BY)

Why make paper angels when you can make paper angelsharks?

Okay, so maybe I got a little carried away when I was clearing scrap paper from my desk. But it’s another opportunity to better know a fish!

Angelsharks (Squatina squatina) are named for their large, wing-like pectoral fins, resembling that of the arching wings of angels in Christian traditions.

But these large fins do not give angelsharks the ability to leap and fly out of the water. Instead, the overall flattened body shape of angelsharks allow them to hug and bury into the ocean floor:

The dorsalventrally flattened body of an angelshark (Squatina squatina) is apparent in this photo. (Image Credit: Philippe Guillaume/CC-BY -2.0)

The dorsalventrally flattened body of an angelshark (Squatina squatina) is apparent in this photo. (Image Credit: Philippe Guillaume/CC-BY-2.0)

Camouflaged and blending into sandy and graveled seafloors, angelsharks wait motionlessly for their prey. If you watch enough nature programs on television, you are probably already familiar with the footage of a Pacific angelshark (Squatina californica) attacking a small horn shark (Heterodontus francisci).

Baby angelsharks get in the action, too, as seen in this clip from Deep Sea World in Fife, Scotland:

The expression on the kid’s face in the background is fantastic. The audible “crunch” of the angelshark bite in this next clip is pretty cool, too:

Reaching a maximum length of almost 6 feet (180 cm) in length — human-sized – Squatina squatina is found in the seas off of northern Africa, Europe and in the Mediterranean. It is one of at least 20 known angelshark species found in various seas around the world, all belonging to Order Squatiniformes.

Angelsharks and their unique bodies have long swam the oceans of our planet. Fossil evidence suggests that angelsharks originated as far back as 157 million years ago — the late Jurassic Period — making them contemporaries of dinosaurs (Klug and Kriwet 2013).

So that’s how far angelsharks go back. But where do they really come from?

Their mothers, of course. And via live birth. Shark reproductive strategies vary widely, and in angelsharks, an embryo develops without placental attachment to the mother, but instead is nourished by an attached yolk sac.

In this BBC News video clip, you can watch the assisted birth of angelshark pups, and see an endoscope view of angelshark embryos in utero.

Another generation born. Now picture this birth taking place in the Jurassic seas…

The angelshark (Squatina squatina) blends into its environment. (Image Credit: Flickr user greenacre8/CC-BY-2.0)

The angelshark (Squatina squatina) blends into its environment. (Image Credit: Flickr user greenacre8/CC-BY-2.0)

Squatina squatina (Linnaeus, 1758)
Angelshark (click for names in other languages)

Class Chondrichthyes (Cartilaginous Fishes)
Order Squatiniformes (Angelsharks)
Family Squatinidae (Angelsharks)

FishBase Page: http://www.fishbase.org/summary/736

Citations

Klug, S., J Kriwet. 2013. Node age estimations and the origin of angel sharks, Squatiniformes (Neoselachii, Squalomorphii). Journal of Systematic Palaeontology 11(1): 91-110. doi: 10.1080/14772019.2012.674066

– Ben Young Landis



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