Genus

Common name: Pencil Urchin

Scientific name: Prionocidaris

Prionocidaris is a genus of sea urchins commonly known as Pencil Urchins. They are characterized by their thick, blunt spines that resemble pencils, hence the name. These urchins are found in various marine environments, often on rocky substrates. They play a role in the ecosystem by grazing on algae, which helps prevent overgrowth. In the aquarium, they can be beneficial for controlling algae, but their size and potential to overturn corals must be considered. They are generally peaceful and can coexist with a variety of tank mates.

  1. Common name: Crown-spined Pencil Urchin
    Scientific name: Prionocidaris baculosa
  2. View of pencil urchin behind corals
    Common name: Pencil Sea Urchin
    Scientific name: Prionocidaris bispinosa