Class Gymnolaemata

[see also Class Stenolaemata]

Order Ctenostomatida

Pherusella brevituba Soule, 1951
Phylum Bryozoa, Class Gymnolaemata, Order Ctenostomatida, Family Alcyonidiidae

Chitinous leathery folded sheets, tan; forms rounded fan-like encrustations on algae; colony appears fuzzy when zooids' large lophophores are extended.

Common, usually encrusting vegetative fronds of Stephanocystis in Monterey region.

Geogr. Range: Monterey Bay(farther north?) to Baja
Synonyms:
Similar species: Pherusella is not rigid & brittle like most other common bryozoans; it is the most abundant foliacious bryozoan on algae.

Bowerbankia
Phylum Bryozoa, Class Gymnolaemata, Order Ctenostomatida, Family Vesiculariidae

Tiny tubular zooids (<0.5 mm tall) interconnected by basal stolons, growing on algae or as minute branching colonies. Appears as a white fuzz or a very delicate hydroid to unaided eye.

Common but inconspicuous; especially on wharf pilings & other fouling communities.

Geogr. Range: Puget Sound to Gulf of California
Synonyms:
Similar species:

Order Cheilostomatida, Suborder Anascina

Membranipora fusca Osburn, 1950
Phylum Bryozoa, Class Gymnolaemata, Order Cheilostomatida, Suborder Anascina, Family Membraniporidae

Encrusting on rocks, colonies orange with darker orange or brownish margins; zooids rectangular with clear frontal membrane & dark orange borders (inset).

Common but inconspicuous on undersides of rocks & in crevices.

Geogr. Range: northern & central California
Synonyms:
Similar species: Membranipora villosa is white & occurs mainly on fronds of kelp & other algae. Celleporella hyalina is white, appears more glassy when not fouled & colonies often have more circular perimeters. Reginella hippocrepis is yellow rather than orange. However, encrusting bryozoans are difficult to identify in the field & require microscopic examination.

Membranipora villosa Hincks, 1880
Phylum Bryozoa, Class Gymnolaemata, Order Cheilostomatida, Suborder Anascina, Family Membraniporidae

Encrusting on kelp or other algae; colonies translucent white; zooids rectangular with clear frontal membrane.

Abundant but variable in time and space. On kelp blades as well as smaller algae.

Geogr. Range: British Columbia to southern California
Synonyms: previously identified as the European Membranipora membranacea, which may not occur along the Pacific coast; the 3 putative speciies of Pacific coast Membranipora (M. membranacea, M.serrilamella, M. villosa) intergrade morphologically w. one another & their separate species status is debated. If M. membrancea is indeed not present, M. villosa has priority; see Dick et al 2005 J.Nat.Hist.39:3687, Schwaninger 2008 Mol.Phylo.Evol.49:893.
Similar species: Membranipora fusca occurs on rocks rather than algae and its zooids are pale orange with dark orange or brown edges.

Bugula neritina Linnaeus, 1758
Phylum Bryozoa, Class Gymnolaemata, Order Cheilostomatida, Suborder Anascina, Family Bicellariellidae

Erect bushy colony, 5-8 cm tall; branches curve slightly inward toward central axis, lightly calcified; dark purple.

Common in sheltered sites such as wharf pilings, Deep Reef; sporadic in kelp forests in Monterey.

Geogr. Range: Monterey Bay to Baja
Synonyms:
Similar species: Bugula californica is tan, its branches stiffer and arranged in spirals around central axis of colony. Scrupocellaria is tan, its branches are not spirally arranged and are flat, not curved.

Image: Phidolopora (cntr rt.), Metridium farcimen (upper left)

Bugula californica Robertson, 1905
Phylum Bryozoa, Class Gymnolaemata, Order Cheilostomatida, Suborder Anascina, Family Bicellariellidae

Erect, bushy, 5-8 cm tall; side branches arranged in distinct spirals around central axis; pale orange to tan.

Spotty but can be common, on rocks in low intertidal and kelp forest depths; also on wharf pilings.

Geogr. Range: British Columbia to southern California
Synonyms:
Similar species: Scrupocellaria is a similar color but its branches are not spirally arranged.

Image: compound tunicate (Diplosoma?) rt. side

Scrupocellaria spp.
Phylum Bryozoa, Class Gymnolaemata, Order Cheilostomatida, Suborder Anascina, Family Scrupocellariidae

Colony erect & branched, 10 cm tall; branches flattened with two rows of zooids on inward-facing side (biserial); flagella-like vibraculae present. Microscopic examination required to distinguish species.

Moderately common, on rocks with other sessile invertebrates & red algae; also on wharf pilings.

Geogr. Range: British Columbia to Baja
Synonyms:
Similar species: Crisia has a similar branching pattern but is smaller and more delicate. Bugula californica is less common in kelp forests & its side branches are arranged spirally around its central axes.

Cellaria mandibulata Hincks, 1882
Phylum Bryozoa, Class Gymnolaemata, Order Cheilostomatida, Suborder Anascina, Family Cellariidae

Colony erect & branched, 5-8 cm tall; with dark joints separating sausage-like internodes; giant avicularia with dark mandible (visible only under a microscope).

Common, but inconspicuous; on rocks among other sessile invertebrates and red algae.

Geogr. Range: British Columbia to Baja
Synonyms:
Similar species: Thalamoporella californica lacks dark joints & occurs more frequently in southern California (rare in Monterey).

Image: Coleopora (middle left), encrusting bryozoan (lower rt.)

Order Cheilostomatida, Suborder Cribimorphina

Reginella hippocrepis (Hincks, 1882)
Phylum Bryozoa, Class Gymnolaemata, Order Cheilostomatida, Suborder Cribimorphina, Family Cribrilinidae

Encrusting, pale yellow with dark yellow margin.

Common, but inconspicuous, on rock faces and undersides of cobbles & boulders, usually with other encrusting bryozoans & often partially overgrown by neighboring invertebrates or algae.

Geogr. Range: Alaska to southern California
Synonyms: Lyrula hippocrepis
Similar species: most encrusting bryozoans are very difficult to identify in the field, though few are as yellow as Reginella.

Order Cheilostomatida, Suborder Ascophorina

Celleporella hyalina (Linnaeus, 1767)
Phylum Bryozoa, Class Gymnolaemata, Order Cheilostomatida, Suborder Ascophorina, Family Hippothoidae

Encrusting colony, usually on red algae. Glassy white; colonies dioecious with larger female feeding zooids and minute dwarf male zooids.

Very abundant, especially on low-lying red algae such as Rhodymenia.

Geogr. Range: Alaska to Galapagos Islands
Synonyms: Hippothoa hyalina
Similar species: this is a complex of several species; other encrusting bryozoans also occur on red algae, but require microscopic examination to distinguish.

Celleporella sp.
Phylum Bryozoa, Class Gymnolaemata, Order Cheilostomatida, Suborder Ascophorina, Family Hippothoidae

Erect to 10 cm tall; branches circular in cross section 3-5 mm diameter; white or cream.

Very common, on rocks in areas with moderate to strong water motion.

Geogr. Range: this is an undescribed species of Celleporella
Synonyms:
Similar species: misidentified in many popular sources as Heteropora magna (which is a cyclostome, not a cheilostome).

Celleporaria brunnea (Hincks,1884)
Phylum Bryozoa, Class Gymnolaemata, Order Cheilostomatida, Suborder Ascophorina, Family Curculionoidea

Encrusting colony of thick lumpy brown or gray crusts; possess giant interzooecial avicularia with black mandible (only visible under a microscope).

Common, especially in protected harbors & wharf pilings.

Geogr. Range: Oregon to Ecuador
Synonyms: Holoporella brunnea
Similar species:

Eurystomella bilabiata (Hincks, 1884)
Phylum Bryozoa, Class Gymnolaemata, Order Cheilostomatida, Suborder Ascophorina, Family Eurystomellidae

Encrusting with visible zooids; rose red to pink.

Common, on rocks, often partially overgrown by other inverts or algae. Preferred prey of pink hopkinsia nudibranch Okenia rosacea.

Geogr. Range: Alaska to Mexico
Synonyms:
Similar species: only rose-pink encrusting bryozoan in Monterey region. Invasive Watersipora usually grows in foliacious erect sheets, but can be just a crust; it is often darker red to nearly black.

Image: Balanophyllia elegans (right)

Coleopora gigantea (Canu & Bassler, 1923)
Phylum Bryozoa, Class Gymnolaemata, Order Cheilostomatida, Suborder Ascophorina, Family Petraliidae

Encrusting with large zooids (1-2 mm) visible to naked eye; aperture round with raised collar-like margin; yellow to pale orange.

Common but inconspicuous; on rocks.

Geogr. Range: Monterey Bay to Baja
Synonyms:
Similar species: the many orangish-tan encrusting bryozoans are very difficult to distinguish in the field.

Celleporina robertsoniae (Canu & Bassler, 1923)
Phylum Bryozoa, Class Gymnolaemata, Order Cheilostomatida, Suborder Ascophorina, Family Celleporidae

Forms low rounded knobs 4 cm tall; bright orange.

Common, on rocks interspersed with other bryozoans and sessile invertebrates.

Geogr. Range: Alaska to Baja
Synonyms: Costazia robertsoniae
Similar species: Lagenicella is more branched & erect (not knob-like), its branches are smaller in diameter, more densely packed, & pale orange or tan rather than bright orange.

Image: Hippoporina insculpta (lower left, middle left); Eudistylia polymorpha (center top); Pisaster giganteus (cntr bottom)

Lagenicella punctulata (Gabb & Horn, 1862)
Phylum Bryozoa, Class Gymnolaemata, Order Cheilostomatida, Suborder Ascophorina, Family Phylactellidae

Erect branched colony 5 cm tall; branches cylindrical 2-3 mm diameter & densely packed; pale orange or tan.

Common, on rocks; colony may cover respectable area; interior of colony provides habitat for many different polychaetes, crustaceans, & other small motile invertebrates.

Geogr. Range: British Columbia to Baja
Synonyms: Lagenipora punctulata
Similar species: Celleporella sp. is white, less densely branched with thicker diameters. Celleporina robertsoniae is bright orange, more knob-like and much less branched.

Image: Reginella hippocrepis (upper rt), Celleporina (upper rt corner), Corynactis californica (left, middle rt.)

Hippoporina insculpta (Hincks, 1882)
Phylum Bryozoa, Class Gymnolaemata, Order Cheilostomatida, Suborder Ascophorina, Family Hippoporinidae

Encrusting base growing into foliacious sheet-like folds; golden brown to orange; no lace-like perforations in colony.

Common, growing on rocks and encrusting blades of red algae.

Geogr. Range: Alaska to central California
Synonyms: Hippodiplosia insculpta
Similar species: Phidolopora pacifica is orange with obvious perforations in colony, giving it a lacy appearance. Invasive Watersipora has similar growth form but is dark rose red rather than golden brown & is more delicate.

Image: Celleporella sp. (upper rt., lower left), Crisia sp. (top rt. corner), compound tunicate (Diplosoma?) overgrowing bryozoans

Phidolopora pacifica (Robertson, 1908)
Phylum Bryozoa, Class Gymnolaemata, Order Cheilostomatida, Suborder Ascophorina, Family Reteporidae

Erect, foliacious, rigid tuft of folded sheets to 10 cm or more across with lace-like perforations throughout colony; bright to pale orange; zooids only on inner faces of folds.

Abundant, on rocks. Often with juvenile Calliostoma annulatum living on colony.

Geogr. Range: British Columbia to Galapagos Islands
Synonyms:
Similar species: no other foliacious bryozoan in Monterey region has perforations throughout colony.

Image: Lagenicella punctulata (lower left); Paracyathus stearnsi (cup coral)

Watersipora subtorquata (d'Orbigny, 1852)
Phylum Bryozoa, Class Gymnolaemata, Order Cheilostomatida, Suborder Ascophorina, Family Watersiporidae

Encrusting base growing into foliacious folded sheets. Dark red to black; zooecia with large black opercula. Colonies rigid, but fragile; erect portions appear to die back periodically (gray portion in photo).

Increasingly common; fast-growing introduced species; on rocks in kelp forests as well as sheltered sites such as harbors & wharf pilings.

Geogr. Range: world-wide distribution
Synonyms:
Similar species: Hippoporina insculpta has a similar foliacious growth form, but is golden brown to pale orange rather than deep rose red and is not nearly so fragile as Watersipora.