Rhizoclonium tortuosum (Dillwyn) Kützing

Rhizoclonium tortuosum (Dillwyn) Kützing

Conferva tortuosa Dillwyn, 1805:pl. 46.

Rhizoclonium tortuosum (Dillwyn) Kützing, 1845:205; Setchell and Gardner, 1920b:185; Chapman, 1939:19; Doty, 1947:25; Dawson, 1961b:376; Blair, 1983:198, figs. 12, 13; Hoffman and Santelices, 1997:91, fig. 19; Bucio-Pacheco and Dreckmann, 1998:44; Pedroche et al., 2005:51.

Chaetomorpha tortuosa (Dillwyn) Kleen, 1874:45; Scagel et al., 1989:62.

Lola tortuosa (Dillwyn) Chapman, 1953:65; Chapman, 1956:463.

Rhizoclonium lubricum Setchell et N. L. Gardner in N. L. Gardner, 1919:492, pl. 42: fig. 5A,B; Setchell and Gardner, 1920b:185, pl. 9: fig. 5a,b; Taylor, 1945:56; Doty, 1947:26.

Lola lubrica (Setchell et N. L. Gardner in N. L. Gardner) A. Hamel et G. Hamel, 1929:1094; Hamel, 1931a:118, fig. 37 (1–5); Dawson, 1944:208; Dawson, 1961b:376; Abbott and Hollenberg, 1976:92, fig. 47; Ortega et al., 1987:78, pl. 14: figs. 63, 64; Scagel et al., 1989:74; Stewart, 1991:32; González-González et al., 1996:137; Paul-Chávez and Riosmena-Rodríguez, 2000:146; Pedroche et al., 2005:49.

Rhizoclonium riparium f. validum Foslie in Wittrock et Nordstedt, 1884:No. 624; Foslie, 1890:139.

Algae of slippery filaments, up to 40 cm long, often entangled or forming free-floating mats; composed of unbranched filaments, (25–)30–75 µm in diameter; newer cells (25–)35–100 µm long; mature cells 120–300 µm long; attached by simple short rhizoids. Cells with a reticulate chloroplast, and numerous pyrenoids; cell wall 0.2 µm thick.

Vegetative reproduction by fragmentation. Reproduction not observed in Gulf material. A life history involving an isomorphic alternation of generations has been reported, with asexual reproduction by quadriflagellate zoospores, and sexual reproduction that is anisogamous,

with biflagellate gametes (Hamel and Hamel, 1929; Blair, 1983).

HABITAT. On rocks or other hard substrata, often entangled with other algae; on mud-sand flats in lagoons and shallow bays; or sometimes unattached and free-floating; mid to low intertidal.

DISTRIBUTION. Gulf of California: Guaymas; Bahía San Gabriel; Isla Espíritu Santo; Laguna de Agiabampo (Sonora). Pacific coast: Alaska to Michoacán.

TYPE LOCALITY. Lectotype: Swansea, Glamorgan, Wales, UK (Blair, 1983:198).