- Blue markers: specimen records
- Yellow marker: type locality, if present
- Red markers: endpoints of range from literature
Pikea Harvey 1853
Thalli with 2 morphological phases: larger, gametangial plants erect, isolated or tufted and arising from small, conical holdfasts; sporangial plants small, crustose, bearing cruciately divided tetrasporangia. Gametangial plants with or without distinct stipe, with or without percurrent axis; major branches somewhat compressed, pinnately branched. Medulla with 1 prominent axial filament, surrounded by rhizoidal filaments, these in mature portions appearing pseudoparenchymatous. Cortex filamentous, of 6-8 dichotomously branched cell rows, forming rigid exterior. Spermatangia superficially produced, in whitish patches at apices of young branches. Development of carpogonial and auxiliary-cell branches as in Farlowia, but differing in formation of gonimoblast in having the cells adjacent to auxiliary cell participating in forming several gonimolobes. Nearly all cells of gonimoblast become carposporangia.
Pikea californica Harv.
Harvey 1853: 246; Smith 1944: 202; Abbott 1968: 182 (incl. synonymy); Scott & Dixon 1971: 295.
Gametangial thalli 5-10(24) cm tall, bushy; several fronds arising from 1 holdfast, deep red, drying to blackish. Branching pinnate; major branches 1-1.5 mm broad, the final orders acutely pointed and spinelike. Tetrasporangia cruciately divided, in crustose phase; development of other reproductive structures as for genus; mature gonimoblasts crowding apices of branches, each apex subterminally swollen and spindle-shaped; gonimoblasts in nemathecioid rows.
Locally frequent, saxicolous, rarely epiphytic, low intertidal to subtidal (20 m), S. Br. Columbia to Pta. Baja, Baja Calif. Also reported from Japan. Type locality: San Francisco, 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.
