Crown-spined Pencil Urchin

Spined like a crown, this urchin is mostly active at night in search for food. Its diet consists of algae, organic waste, snails, mussels, tubeworms but also corals and sponges, making it therefore a risk to keep in a reef aquarium.

House the Pencil Urchin in matured aquariums due to their algae consumption. Due to the sensitivity of these animals to changes, we recommend keeping the water parameters – especially the salinity level – constant.

Be careful when keeping them in a fish-only system as they are on the menu of trigger fishes and big wrasses. Sea urchins do not have brains but it is believed their entire nervous system acts like a brain. They are able to avoid predators and finding hiding places without any apparent eyes, but the question is, how? Research has shown they have light-sensitive molecules in their spines and as a result their entire body acts as one big eye.

Prionocidaris baculosaUp to 20 cm.
Indo-West Pacific OceanTemperature: 22 – 28 °C
pH: 8,0 – 8,4
Sg: 1.023 – 1.025
This is a debatable ‘fun’ fact 😅 They have the reputation of being a bulldozer, making them more suitable for Fish Only Tanks. Their spines can break off but regenerate again.

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