Sea cucumber

Though the echinoderm phylum is still large, diverse, and ecologically significant, there was a time when at least twenty classes existed on Earth, as is evidenced by the fossil record.

Today, the five extant echinoderm classes are Crinoidea, Asteroidea, Ophiuroidea, Echinoidea, and Holothuroidea.

It's worth mentioning that although there is widespread consensus that these five classes are distinct, the exact number and relationship between orders within a class, and even the total number of orders, is still a subject of ongoing research.

In this tutorial, we will cover the least diverse of the echinoderm classes, the crinoids.

He knows a lot about the science stuff, Professor Dave explains.

As we discussed previously, the five extant echinoderm classes are Crinoidea, Asteroidea, Ophiuroidea, Echinoidea, and Holothuroidea.

In the previous tutorial, we covered the crinoids.

In this tutorial, we will discuss Asteroidea and Ophiuroidea.

You see its kinda weird little tail? Because of that, they have named it Loki, and Loki is one of 57 new species discovered in the deep sea canyon near Argentina.

Now, this is a sea cucumber, Loki the sea cucumber they call it.

One of m- many newly discovered marine species in the South Atlantic Ocean, these creatures discovered during the expedition of Mar del Plata submarine canyon off the coast of Argentina about a year ago.

This is an area, it's called the Brazil Malvinas Confluence, and it is where the warm subtropical currents collide with cold nutrient rich sub-Antarctic waters.

And what you get is this, they call it a crossroad bustling with biodiversity.

The submarine canyon itself is nearly twice as deep as the Grand Canyon, so more than 11,000 feet.

They said among this new crop of ocean dwellers is here we have pictured Loki the sea cucumber.

Named for its appendages which resemble the Norse god of mischief's horns, Loki was discovered at 8,454 feet deep.

Remember, this is just a basic guideline of echinoderm classification, which may change over time.

Lastly, we have class Holothuroidea, whose members are often commonly referred to as sea cucumbers.

Like most echinoderms, these are found in oceans worldwide.

They differ from other echinoderms in that they are elongated and bear gr-