UC specimens and range limits for Codium fragile subsp. californicum

• Blue markers: specimen records
• Yellow marker: type locality, if present
• Red markers: endpoints of range from literature

View map from the Consortium of Pacific Northwest Herbaria

Notes: Northern records: Rockwell Island, Sitka Harbor, Alaska, UBC-A43990. Southern records: Thurloe Bay, Puerto San Bartolome, Baja California, Mexico, MICH-726449; Isla San Benito, Baja California, near Punta Abreojos, Baja California, WTU-A-000528.

Status: The most common and widespread erect species of Codium on our coast. Confirmed by DNA sequence from "Bird Rock, California", collected by D. Kapraun in 1980 (Provan et al. 2007).

Habitat: Low intertidal to subtidal, moderately to fully exposed environments

Life History: Diploid unisexual or bisexual macroscopic thallus arising from perennating fibrous base; sexual reproduction anisogamous, zygote developing into pancake-like stage from which gametophyte eventually arises (Borden and Stein 1969; Smith 1930); parthenogenesis possible.

Search Sequences in GenBank

Illustration from DeCew's Guide to the Seaweeds of British Columbia, Washington, Oregon, and Northern California

Codium Stackhouse 1797

Thalli much branched, the branches compacted and forming erect or prostrate, noncalcareous spongy thallus of definite form, basally attached by rhizoids. Surface layer composed of palisade-like, photosynthetic, enlarged branch tips (utricles). Interior of thallus composed of slender, colorless, intertwined tubular branches. Thalli mostly dioecious; gametangia fusiform to cylindrical, borne laterally on utricles and sealed off at base by annular thickenings. Gametes biflagellate, anisogamous, formed following meiosis. Zygote developing directly into diploid plant.

Codium fragile (Sur.) Har.

Acanthocodium fragile Suringar 1867: 258. Codium fragile (Sur.) Hariot 1889: 32; Smith 1944: 75; Silva 1951: 96 (incl. synonymy).

Thalli erect, dark green to blackish-green, 10-30(41) cm tall, with 1 to several erect branches from broad basal disk, abundantly dichotomo-fastigiately branched; the branches cylindrical, 3-8(10) mm diam.; utricles unbranched, narrowly to broadly clavate, 150-350(630) µm diam., 600-1500 µm long, with mucronate apex, hairs absent to abundant.

Frequent to common, intertidal on tops and sides of rocks, occasionally subtidal (to 45 m), Sitka, Alaska, to Bahia Asuncion, Baja Calif. Widely distributed in temperate seas. Type locality: Japan.

Excerpt from Abbott, I. A., & Hollenberg, G. J. (1976). Marine algae of California. Stanford University Press, Stanford, California. xii [xiii] + 827 pp., 701 figs.

Notes: Codium fragile subsp. californicum was distinguished from the Japanese C. fragile by Brodie et al. (2007). Provan et al. (2007) demonstrated that morphology and utricle anatomy fail to distinguish regional subspecies and the invasive strain of C. fragile from one another.

In warm water conditions in southern California, hairs are extremely abundant, forming a halo around the axes. Common in the subtidal.