- Blue markers: specimen records
- Yellow marker: type locality, if present
- Red markers: endpoints of range from literature
Gigartina Stackhouse 1809
Thalli with peglike or discoid holdfasts; fronds gregarious, relatively elongate, cylindrical or compressed to foliaceous, multiaxial, thickly or sparsely beset with papillate outgrowths, some of these clearly vegetative, others carrying reproductive structures. Medulla of delicate, cobwebby, anastomosing filaments, or with cells of various shapes and sizes. Cortex uniform, relatively thin, the cells small, oval to spherical, in 4-6(15)-celled anticlinal rows. Most species with tetrasporangial thalli similar in size and shape to gametangial thalli; in 2 species (G. agardhii and G. papillata) tetrasporangial plant crustose, not resembling erect thalli. Tetrasporangia developed from innermost cortical cells, cruciately divided, in globose to flattened sori on fertile papillae, or in chains in separate crustose stage. Spermatangia in irregularly shaped, continuous, confluent, superficial patches on papillae, sometimes spreading to flat surface of thallus; in some species entire thallus smooth, mostly without papillae, and lighter in color when spermatangial. Cystocarps making prominent bulges on papillae, in some species changing appearance of sterile thallus completely; firm, dense, internal ring of sterile tissue surrounding carposporangia.
Different species of Gigartina tend to occur in characteristic tidal zones.
Gigartina corymbifera (Kütz.) J. Ag.
Mastocarpus corymbiferus Kützing 1847: 24. Gigartina corymbifera (Kütz.) J. Agardh 1876: 202; Setchell & Gardner 1933: 275; Smith 1944: 281 (incl. synonymy). G. binghamiae J. Ag. 1899: 33; Dawson 1961a: 267.
Thalli in clumps of large, crisp blades, to 1+ m long, to 30 cm wide; blades generally with stout holdfasts and strap-shaped apophyses, these 4-5 cm wide, somewhat flared upwardly at bases of blades; holdfasts and apophyses usually smooth; blades of various sizes and ages in clumps; young blades and basal portion of old blades iridescent; older blades yellowish-pink when plants in low intertidal, the plants uniformly bluish-rose when subtidal; medulla with filaments of variety of sizes and shapes; papillae very coarse, commonly 1-2 cm long, obtuse and occasionally bifurcate if tetrasporangial, acuminate and slender if spermatangial, short and mammillose (often corymbose) if cystocarpic, commonly with 2 or 3 terminally branched cystocarps per papilla.
Common, saxicolous, low intertidal (in areas exposed to surf and surge) to subtidal (30 m), Whidbey I. and Cape flattery, Wash., to Cabo San Quintin, Baja Calif. Type locality: probably Monterey, Calif.
Excerpt from Abbott, I. A., & Hollenberg, G. J. (1976). Marine algae of California. Stanford University Press, Stanford, California. xii [xiii] + 827 pp., 701 figs.
