Burrowing Sea Cucumber

Massinium magnum

Also known as Echinoderms, Burrowing Sea Cucumber and Sea Basket Sea Cucumber. Found singly buried in the sand of shallow waters on sand and rubble areas. They feed on plankton.
Burrowing Sea Cucumber (Massinium/Neothyonidium magnum) Madidir III, Lembeh. In the next two pics I show how it starts retracting its tentacles as it feels me getting closer. https://www.jungledragon.com/image/66382/.html https://www.jungledragon.com/image/66383/.html Video of the same sea cucumber: https://youtu.be/sZOAGogwcWU You can see how it approached its tentacles to its mouth one at a time to get food. Burrowing Sea Cucumber,Geotagged,Indonesia,Massinium magnum,Spring

Appearance

Length - 30cm.
Massinium/Neothyonidium magnum Madidir III, Lembeh. I think this sea cucumber may be older than that of the previous posting as it is larger also. Another video of this one feeding: https://youtu.be/M42kxT4dMAs Burrowing Sea Cucumber,Geotagged,Indonesia,Massinium magnum,Spring

Naming

Genus synonym: Neothyonidium.
Burrowing Sea Cucumber - Massinium magnum Burrowing Sea Cucumber,Fall,Geotagged,Indonesia,Massinium magnum

Distribution

Depth - 0-40m, Widespread Indo-Pacific
Large Burrowing Sea Cucumber - Massinium magnum Burrowing Sea Cucumber,Indonesia,Komodo,Large Burrowing Sea Cucumber,Massinium magnum,Sea Cucumber

Behavior

When feeding they fan out their "arms" and then one by one roll them in into their mouths to feed.

References:

Some text fragments are auto parsed from Wikipedia.

https://www.whatsthatfish.com/fish/magnum-sea-cucumber/1764
https://reefguide.org/neothyonidiummagnum.html
http://www.marinespecies.org/aphia.php?p=taxdetails&id=529531
Taxonomy
KingdomAnimalia
DivisionEchinodermata
ClassHolothuroidea
OrderDendrochirotida
FamilyPhyllophoridae
GenusMassinium
SpeciesMassinium magnum
Photographed in
Indonesia