Florent's Guide To The

Tropical Reefs

Slate Pencil Urchin
Eucidaris tribuloides
Slate Pencil Urchin
Category: Pencil Urchins
Scientific Name: Eucidaris tribuloides
Size: 1 to 2 in. (2 to 5 cm)  
Depth: 3-160 ft. (1-50 m)
Distribution: Caribbean, Bahamas, Florida, Brazil
Echinodermata (Phylum)
└Echinozoa (Subphylum)
 └Echinoidea (Class)
  └Cidaroidea (Subclass)
   └Cidaroida (Order)
    └Cidaridae (Family)
     └Eucidaris (Genus)
      └E. tribuloides (Species)

Echinoderms
Pencil Urchins

Slate Pencil Urchin

Rough-Spined Urchin

East Pacific Slate Pencil Urchin



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© 2026 Florent Charpin