Other Phyla - sponges, worms, etc.

Haliclona sp. A (Hartman, 1975)
Phylum Porifera, Class Demospongiae, Order Haplosclerida, Family Chalinidae

Purple sponge; thin crust 2-3 mm thick with raised tubular oscula 1-3 mm diameter.

Moderately common on sides of rocks, but spotty in space and time; mid- to low intertidal zones, protected outer coast; only sponge to occur on open rock this high on the shore.

Geogr. Range: central to southern California
Synonyms: formerly thought to be the Atlantic Haliclona permollis
Similar species: this is the only sponge that lives this high in the intertidal zone; all other  sponges occur much lower and into the subtidal.

Image: dark brown crust is Petrocelis phase of (probably) Mastocarpus papillatus.

Oscarella carmela Muricy & Pearse 2004
Phylum Porifera, Class Demospongiae, Order Homosclerophorida, Family Plakinidae

Encrusting sponge; skeleton absent (no spiclules); thin soft slimy crust 2-3 mm thick, raised into small lumps or lobes; superficially resembles a compound ascidian; color tan to light brown or pale reddish orange; ovoid choanocyte chambers (only visible under a microscope).

Very patchy, on sides and underneath boulders submerged in tidepools in the high intertidal zone; also in aquarium facilities.

Geogr. Range: central California,  north at least to Vancouver
Synonyms:
Similar species: Halisarca sp. also lacks spicules but possesses elongate tubular choanocyte chambers.

Image: from underside of a boulder; white spots are spirorbid polychaetes.

Phragmatopoma californica (Fewkes, 1889)
Phylum Annelida, Class Polychaeta, Order Sabellida, Family Sabellariidae

Tubes 3-4 mm diameter of cemented sand grains with short purple tentacles & operculum protruding; worm to 5 cm; often in large aggregations (from gregarious larval settlement, not asexual division).

Common; can form large reefs several meters across & >50 cm thick; mid- to low intertidal zones & subtidal; protected outer coast.

Geogr. Range: central California to Baja
Synonyms:
Similar species: Sabellaria cementarium is mostly subtidal, has golden tentacles instead of purple and doesn't form large reef-size aggregations.

Image: Cladophora (green tuft, top center), Mazzaella leptorhynchos (top, left of center), Anthopleura sola (right side)

Dodecaceria fewkesi Berkeley & Berkeley, 1954
Phylum Annelida, Class Polychaeta, Order Terebellida, Family Cirratulidae

Small to medium worm; 40 mm long, with dark green- black body; crown of 12 tentacles 1-2 mm in diameter surrounds mouth; colony forms by asexual fission of single original founder; at low tide hard solid masses of fused calcareous tubes resemble concrete riddled with tiny holes.

Locally abundant on rocks, mid- to low intertidal zones & subtidal; protected outer coast.

Geogr. Range: British Columbia to southern California
Synonyms:
Similar species: subtidal D. fewkesi grow as clusters of  larger erect tubes; smaller Dodecaceria concharum bore into calcareous material such as crustose corallines & do not occur in the intertidal zone.

Image: contracted Anthopleura elegantissima (across top).

Nereis grubei (Kinberg, 1866)
Phylum Annelida, Class Polychaeta, Order Phyllodocida, Family Nereidae

Segmented worm, to 100 mm long; often bright green/blue-green with large prostomial palps & eversible proboscis with jaws.  

Common but cryptic; builds mucus tubes in algal fronds, holdfasts, or mussel beds in mid-intertidal to subtidal zones; omnivorous.  Individual in photo is becoming  reproductive (epitokous) as evidenced by it's pinkish posterior end and enlarged eyes on head.

Geogr. Range: British Columbia to Mexico; Peru
Synonyms:
Similar species: numerous spp. of mobile "errant" polychaetes live on rocky shores, but most are cryptic, small, or both.

Phascolosoma agassizii Keferstein, 1867
Phylum Sipuncula, Family Phascolosomatidae

Peanut worm. Small bulbous body with extensible tubular introvert (burrowed into shell rubble in photo); length 5-12 cm (half of which is introvert); mouth at end of introvert partially surrounded by short finger-like tentacles; body covered with short conical papillae; color tan to dk. brown w. dk. brown or purplish spots.

Abundant under rocks, among mussels, holdfasts, roots of surf grass, or nestled in crevices; mid- to low intertidal zones & subtidal; protected outer coast; deposit feeder.

Geogr. Range: Alaska to Baja
Synonyms:
Similar species:

Notocomplana acticola (Boone, 1929)
Phylum Platyhelminthes, Class "Turbellaria," Order Polycladida, Suborder Acotylea, Family Leptoplanidae

Flatworm, to 60 mm long (most < 30 mm) with tapering body; tan to pale gray with dk. brown markings near midline.

Most common intertidal flatworm; under rocks, lower portion of high to mid-intertidal zones; exposed & protected outer coast; very photonegative. Preys on small limpets, barnacles & other invertebrates.

Geogr. Range: California coast
Synonyms: Notoplana acticola
Similar species: numerous spp. of flatworms live on rocky shores, but most are rare or cryptic.

Pseudoalloioplana californica (Heath & McGregor, 1912)
Phylum Platyhelminthes, Class "Turbellaria," Order Polycladida, Suborder Acotylea, Family Planoceridae

Flatworm, to 24 mm long with firm oval body; tan to olive with reticulating dark brown branches of gut visible through body wall.

Moderately common, but intermittent; under rocks lying in gravel or shell rubble, upper mid-intertidal zones; exposed & protected outer coast; very photonegative. Probably preys on small snails & other invertebrates.

Geogr. Range: California coast
Synonyms: Alloioplana californica
Similar species: numerous spp. of flatworms live on rocky shores, but most are rare or cryptic.