- Blue markers: specimen records
- Yellow marker: type locality, if present
- Red markers: endpoints of range from literature
Hymenena Greville 1930
Thalli differentiated into prostrate, ribbonlike portions and erect blades. Blades undivided to much divided; divisions linear, spatulate, palmately or flabellately divided, monostromatic in upper portions and along edges, polystromatic through center and basally. Veins microscopic, or sometimes macroscopic, these several cells thick, without internal rhizoids. Tetrasporangia in sori, these small and scattered over blade, elliptical and in linear series, or in transverse bands across upper segments. Spermatangia, where known, in areolate sori scattered over blade. Cystocarps scattered over blade, or lateral to midline of branches, sometimes extending into marginal proliferations.
Hymenena flabelligera (J. Ag.) Kyl.
Nitophyllum flabelligerum J. Agardh 1876: 699. Hymenena flabelligera (J. Ag.) Kylin 1924: 83; Smith 1944: 348.
Thalli in deep salmon to dull rose clusters, 10-25(30) cm tall, subdichotomously or palmately divided into many linear-lanceolate divisions; lower portions with distinct midribs in each division, these persisting upward and finally disappearing in upper lobes; midribs frequently abraded, appearing stipelike; margins of male plants ruffled, those of cystocarpic and tetrasporangial plants usually plane or slightly dentate; tetrasporangia in narrow, linear sori, these in parallel, long, longitudinally forking rows on upper half of blade; spermatangial sori not clearly shaped, giving divisions a pale, straw-colored cast; cystocarps scattered near margins.
Frequent in exposed places, saxicolous, low intertidal to subtidal (to 12 m), Vancouver I., Br. Columbia, to San Luis Obispo Co., Calif. Type locality: San Francisco, Calif.
A very common species; when very mature and eroded, it is difficult to distinguish from Botryoglossum farlowianum.
Excerpt from Abbott, I. A., & Hollenberg, G. J. (1976). Marine algae of California. Stanford University Press, Stanford, California. xii [xiii] + 827 pp., 701 figs.