UC specimens and range limits for Prasiola meridionalis

• Blue markers: specimen records
• Yellow marker: type locality, if present
• Red markers: endpoints of range from literature

View map from the Consortium of Pacific Northwest Herbaria

Status: This species has been shown to be have the same, or nearly the same, tufA, SSU and rbcL sequences as the Atlantic species Prasiola stipitata Suhr ex Jessen (Saunders & Kucera 2010, Moniz et al. 2014), but these species have not been formally merged. Confirmed by DNA sequence from: Amalik Bay, Alaska; False Creek Yacht Club, British Columbia, Canada; Friday Harbor, Washington; Deadman Bay, Washington; Newport, Oregon; Humboldt Bay, Humboldt Co. and Bodega Bay, Sonoma Co., California (Moniz et al. 2014).

Habitat: Splash zone or uppermost intertidal, enriched with gull guano, in exposed environments

Life History: Sexual reproduction by biflagellate male gametes and non-flagellate female gametes produced following somatic meiosis in packets in different areas of the same diploid leaflike plant; recycling by means of aplanospores (Cole and Akintobi 1963). Bravo (1962, 1965) interpreted the results of her culture studies as showing that Prasiola meridionalis and Rosenvingiella constricta are phases in the same life history. Recent molecular analyses have shown that she was in error, and that these are separate species (e.g., Moniz et al. 2014).

Search Sequences in GenBank

Prasiola Meneghini 1838

Thalli foliaceous, monostromatic, the blades commonly stipitate, the plant frequently with rhizoidal attachment. Cells cubical or elongate to rounded, commonly in groups of 4, repeatedly dividing and forming longitudinal and transverse rows. Vegetative reproduction by abscission of marginal strips. Asexual reproduction by aplanospores or akinetes. Some species with zoospores and motile gametes, having morphologically similar gametangial and sporangial stages in the life history.

Prasiola meridionalis S. & G.

Setchell & Gardner 1920a: 291; 1920b: 278; Smith 1944: 53; Bravo 1965: 177. Gayella constricta S. & G. 1917: 384. Rosenvingiella constricta (S. & G.) Silva 1957b: 41.

Blades deep green, broadly ovate, with crisped margins, to 8(10) mm tall, 40-45 µm thick; cells cubical or anticlinally elongate, mostly 5-8 µm diam., 14-20 µm long; cylindrical form (= Rosenvingiella) and diploid spores reported to be formed during summer and fall, haploid gametes during winter; sexual reproduction oogamous.

Frequent to locally abundant, mostly in spray zone on exposed rock coated with guano, Friday Harbor, Wash., to Carmel and Santa Cruz I., Calif. Type locality: entrance to Tomales Bay (Marin Co.), 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.

Notes: Rosenvingiella constricta is not a synonym, but is rather a separate species, now Rosenvingiellopsis constricta (Setchell & Gardner) S. Heesch, M. Pazoutova & F. Rindi (Moniz et al. 2014). NB: Type locality is Neah Bay, Washington.