Nudechinus
Nudechinus is a genus of sea urchins in the family Echinometridae. The genus currently contains only one species, Nudechinus grayi. They are commonly known as slate pencil urchins due to their distinctive shape and coloration.
Characteristics
Slate pencil urchins are characterized by their flattened, oval-shaped test (shell), which is typically covered in short, blunt spines. The spines are often arranged in a radial pattern, giving the urchin a somewhat star-like appearance. The color of the spines can vary, ranging from dark gray to black. These urchins also have distinctive, small, white "pencils" or "teeth" that project outwards from the test. These pencils are used for scraping algae from surfaces.
Habitat and Distribution
Nudechinus grayi is found in the intertidal and shallow subtidal zones of the Pacific Ocean. It is native to the eastern Pacific, ranging from British Columbia, Canada, to Baja California, Mexico.
Ecology
Slate pencil urchins are herbivores and play a significant role in the marine ecosystem by grazing on algae. They are also an important food source for a variety of predators, including fish, sea stars, and sea otters.
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