WHATSTHATFISH
Sea stars & urchins

Imperial Sea Urchin

Phyllacanthus imperialis

Also known as: Imperial Lance Urchin, Imperial Urchin, Knobby Sputnik Sea Urchin, Lance Urchin, Land Mine Sea Urchin, Mine Urchin, Pencil Sea Urchin, Pencil Urchin, Sea Hedgehog, Sputnik Sea Urchin, Sputnik Sea Urchin Seashell, Sputnik Urchin

Adult
@blogie · Isla Reta Beach Resort, Talikud Island, Island Garden City of Samal, Philippines · October 20111 / 2
01

Overview

Found singly, during the day hiding in holes and hollows, venturing out to feed at night, over shallow reefs. Their spikes vary in colour.

Sea Urchins use tubed feet to get around, often in large impenetrable masses for protection.
Sometimes they hitch a lift on the back of crabs.
They have well developed jaws for grinding their prey.
Their anus is on top in most sea urchins, except the heart urchins where it is at the rear.
Predators of sea urchins are triggerfish and large wrasses, who nibble away at their spines before turning them over to eat the fleshy undersides.
Sea Urchins are highly venomous and can piece through a wet-suit.
Some are sensitive to light and have the ability to shoot venom loaded spines at a short distance.
To be avoided.

02

How to identify

Body shape
fingers

Tap any trait to see other fish that share it.

03

Habitat & where to find it

  • Range · Indo-West Pacific
  • Country only · 2
LIVES IN

Found singly, during the day hiding in holes and hollows, venturing out to feed at night, over shallow reefs.

04

Adult photos 2

05

Discussion

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    ALL STAGES
    FOR THE MARINE-BIOLOGY CURIOUS

    Deep dive

    Taxonomy

    1. kingdomAnimalia
    2. phylumEchinodermata
    3. classEchinoidea
    4. orderCidaroida
    5. familyCidaridae
    6. genusPhyllacanthus
    7. speciesPhyllacanthus imperialis (Lamarck, 1816)

    SourcesWoRMSWikipedia

    06

    More in the family

    Cidaroida