Class Ophiuroidea

Ophiothrix spiculata  Le Conte, 1851
Phylum Echinodermata, Class Ophiuroidea, Order Ophiurida, Family Ophiotrichidae

Disk diameter to 15 mm, arms to 85 mm; arms with prominent marginal spines each with microscopic thornlike spinelets. Color & markings vary enormously from green, brown, orange & yellow with red maroon, brown, pink or white markings. Arms autotomize readily.

Very abundant, cryptic, nestled in kelp holdfasts, under rocks, etc. Scavenger, deposit & suspension feeder.  Extends 2-3 arms from cryptic location & captures fine particulate matter using sticky mucus on podia.

Geogr. Range: central California to Galapagos Islands  
Synonyms:
Similar species: Ophiopteris papillosa is often larger in Monterey region, with thicker more robust arms.

Ophiopteris papillosa  (Lyman, 1875)
Phylum Echinodermata, Class Ophiuroidea, Order Ophiurida, Family Ophiocomidae

Disk diameter to 18 mm, arms to 70 mm; disk densely granulated; arm spines flattened.  Black, pale brown or red with dark bands on arms. Arms autotomize readily.

Abundant but patchy, under cobbles & other cryptic microhabitats. Very photonegative and active when disturbed.

Geogr. Range: British Columbia to Baja
Synonyms:
Similar species: Ophiothrix spiculata is more brightly colored and has more delicate lateral arm spines.

Ophioplocus esmarki  Lyman, 1874
Phylum Echinodermata, Class Ophiuroidea, Order Ophiurida, Family Ophiolepidae

Disk round to 22 mm, arms to 60 mm; gray-brown; lateral arm spines very short.

Common; one of the few ophiuroids visible during daylight hours.  Sluggish & relatively unresponsive; arms do not autotomize easily, but are often found regenerating from being nipped off by fishes.

Geogr. Range: Central California to San Diego
Synonyms:
Similar species:

Amphiura arcystata  H.L. Clark, 1911
Phylum Echinodermata, Class Ophiuroidea, Order Ophiurida, Family Amphiuridae

Very long arms to 30 cm protruding from sand are usually all that's visible of this species.

Very abundant in sand where water motion is low; in Monterey occurs in deeper sites. Suspension & deposit feeder.

Geogr. Range: British Columbia to southern California (at least)
Synonyms:
Similar species: