Eucidaris

Eucidaris is a genus of sea urchins in the family Cidaridae. These urchins are distinguished by their long, slender spines, which are often tipped with red or orange. They are found in a variety of marine environments, including coral reefs, rocky shores, and seagrass meadows. They are generally considered to be herbivores, feeding on algae and other plant matter. They play an important role in their ecosystems by grazing on algae and helping to maintain the health of the reef.

Ten-lined Urchin – Eucidaris metularia

Common Names

Members of this genus are commonly known as "slate pencil urchins" or "red-spined sea urchins".

Characteristics

The genus Eucidaris is characterized by the following:

  • Long, slender spines, often tipped with red or orange.
  • A test (shell) that is typically covered in small, granular plates.
  • A mouth that is surrounded by five teeth.
  • A madreporite (a small, porous plate that allows water to enter the vascular system) that is located on the aboral surface (the side opposite the mouth).
  • They are typically 5-10 cm in diameter, but some species can reach up to 20 cm.

Environment

Eucidaris urchins are found in a variety of marine environments, including:

  • Coral reefs
  • Rocky shores
  • Seagrass meadows

They are generally found in shallow water, but some species can live in deeper water. They are often found in association with algae, which they feed on.

References

For more detailed information, refer to the following resources:

These resources provide detailed taxonomic information, distribution maps, and other data on the genus Eucidaris.