- Blue markers: specimen records
- Yellow marker: type locality, if present
- Red markers: endpoints of range from literature
Lithothrix Gray 1867
Thalli of crustose bases and articulated fronds. Intergenicular medulla of a single tier of short cells. Genicular medulla of a single tier of long cells, uncorticated but surrounded by calcified flange of cortical tissue, this produced by the surmounting intergeniculum. Branch apices with cover cells. Secondary pit-connections present; intercellular fusions lacking. Conceptacles lateral, uniporate, developing from cortical tissue.
Lithothrix aspergillum Gray
Gray 1867: 33; Manza 1940: 296; Smith 1944: 231 (incl. some synonymy); Segawa 1947: 87. Amphiroa aspergillum f. nana Setchell & Gardner 1903: 359. Lithothrix aspergillum f. nana (S. & G.) Yendo 1905: 14.
Thalli saxicolous, occasionally epizoic; fronds clustered, to 13 cm tall, dull purple; primary branching dichotomous, but irregularly distributed lateral branches sometimes abundant; lower intergenicula terete, +/- 0.5 mm long, 0.5-1 mm broad; upper intergenicula in main branches terete or often compressed, +/- 1 mm long, 1-1.5 mm broad, those in secondary branches smaller; conceptacles 350-450 µm diam.; most collected plants bisporangial; tetrasporangial, male, and female specimens known from San Diego Co.
Locally abundant on rocks or animals in sandy areas in lower intertidal, Br. Columbia to S. Baja Calif. Type locality: Vancouver I., Br. Columbia.
Excerpt from Abbott, I. A., & Hollenberg, G. J. (1976). Marine algae of California. Stanford University Press, Stanford, California. xii [xiii] + 827 pp., 701 figs.
