Goniocidaris

Goniocidaris is a genus of sea urchins belonging to the family Cidaridae. They are commonly known as “slate pencil urchins” due to the shape and texture of their spines. This genus is characterized by its distinctive, flattened, and often brightly colored tests (the hard, calcified shell).

Common Names

The common name "slate pencil urchin" is attributed to the shape and texture of the spines, which resemble slate pencils. The name "pencil urchin" is also sometimes used, though it is less specific and can refer to other urchin genera.

Characteristics

Goniocidaris species exhibit several defining characteristics:

  • Test: Flattened and usually circular or slightly oval-shaped.
  • Spines: Long, slender, and often flattened, resembling pencils. They can be brightly colored and are often banded or spotted.
  • Tubercles: The spines are attached to the test through prominent, rounded tubercles that are often arranged in a radial pattern.
  • Coloration: The test and spines can be various colors, including shades of red, orange, yellow, purple, and green.

Environments

Goniocidaris species are found in a variety of marine habitats, primarily in tropical and subtropical waters around the world. They are often found in coral reefs, rocky shores, and seagrass beds, where they feed on algae and other small organisms.

References

World Register of Marine Species (WoRMS)

ResearchGate: Goniocidaris tuberculata (Lamarck, 1816) (Echinoida: Cidaridae): New records and first information about its reproductive biology in the southwestern Atlantic Ocean