- Blue markers: specimen records
- Yellow marker: type locality, if present
- Red markers: endpoints of range from literature
Illustration from DeCew's Guide to the Seaweeds of British Columbia, Washington, Oregon, and Northern California
Laurencia spectabilis Post. & Rupr.
Postels & Ruprecht 1840: 16; Smith 1944: 377; Dawson 1963b: 464.
Thalli to 30 cm tall, with several erect, decompound, compressed axes arising from conical base; branching pinnately alternate to subopposite, pyramidal or flabellate, with branches short above and progressively longer below; lower branches deciduous, or eroding, leaving lower axes more or less naked; branch apices rounded; tetrasporangia in short, dichotomously branched branchlets; spermatangial pockets adaxial on smaller branchlets; cystocarps ovoid on smaller branchlets.
Laurencia spectabilis var. diegoensis (Daws.) Daws.
Laurencia diegoensis Dawson 1944b: 236. L. spectabilis var. diegoensis (Daws.) Daws. 1963b: 465.
Thalli mostly 8-28 cm tall, deep reddish-brown, with general features of var. spectabilis but with narrower branches, 2-3 mm broad, at relatively longer intervals of 6-10(17) mm; branches of different orders of variable length, resulting in asymmetrical appearance of frond; spermatangial pockets in prominent adaxial secund series on smaller branchlets.
Frequent on rocks, midtidal to mostly lower intertidal, Carpinteria (Santa Barbara Co.), Calif., to Pta. Baja, Baja Calif. Type locality: La Jolla, Calif.
Laurencia spectabilis var. spectabilis
Intertidal thalli deep purplish-red; northern and subtidal Calif. thalli rose red, to 30 cm tall; axes 3-5(6) mm broad; branching mostly symmetrical; branches markedly compressed with broadly rounded apices, borne at intervals of 2-8 mm above.
Frequent to common on rocks, midtidal to low intertidal and occasionally subtidal (to 15 m), Sitka, Alaska, to northern Santa Barbara Co., Calif.; infrequent to San Diego, Calif., and in upwelling cold water off Baja Calif. Type locality: Norfolk Sd., Alaska.
Laurencia spectabilis var. tenuis Daws. Dawson 1963b: 466.
Thalli similar to var. diegoensis but much more slender, with main axes 0.7-1.2 mm broad, less compressed than preceding varieties.
Infrequent, saxicolous or epiphytic, intertidal to subtidal, Santa Catalina I. and Pt. Loma (San Diego Co.), Calif., to I. Guadalupe, Baja Calif. (type locality).
Excerpt from Abbott, I. A., & Hollenberg, G. J. (1976). Marine algae of California. Stanford University Press, Stanford, California. xii [xiii] + 827 pp., 701 figs.
