Type locality: Turn Island, San Juan Islands, Washington (Dawson 1962: 72). Type: H. Kylin; Agardh Herbarium Lund, Sweden (Dawson 1962: 72). Notes: Dawson (1962: 72) notes that the type specimen was dredged from a depth of 5-10 fms.
Etymology: Griffithsia was named in honor of Amelia W. Griffiths; and the pacifica refers to the fact that this species is restricted to or pertaining to the Pacific Ocean.
Fig 1. Griffithsia pacifica. Scale bar = 1cm
Plants orange to pink, 3-5 cm tall; Thallus monosiphonous tufted-filamentous, made up of uniseriate connected, relatively large typically barrel-shaped cells (usually clearly visible to the naked eye – without magnification); laterally or almost dichotomously branched; often with terminal repeatedly dichotomously divided hairs (Braune & Guiry 2011).
North America: Alaska (Scagel et al. 1989), Baja California (Dawson 1962), British Columbia (Scagel et al. 1989), California (Abbott & Hollenberg 1976, Scagel et al. 1989, Stewart 1991, Miller 2012), Gulf of California (Dawson 1944, Dawson 1962), Oregon (Hansen 1997), Washington (Scagel et al. 1989). Central America: Islas Revillagigedo (Taylor 1945). South America: Galápagos Islands (Taylor 1945, Ruiz & Ziemmeck 2011), Peru (Ramírez & Santelices 1991).
Regional Distribution (based on FHL Herbarium Collection ): Hein Bank , dredged, 1993; Brown Island, 1961; San Juan Island , 1961; Brown Island 1961; Brown Island, 1915; Dredged Louver Littoral, 1910; Cliff Island, 1916; Friday Harbor, 1907; Dredged Frost Island, 1957; Vancouver Island, 1964;
Herbarium species and slide housed at FHL Herbarium (under the PHYKOS number 00145).
5. Research Notes.
San Juan Island is the type location for this species, which was firstly described in the original publication of Kylin (1925). The thalli is tuffed, 3-5 cm tall, orange-pink, branching regularly dichotomous in lower parts, irregular in terminal portions (fig. 1); bases frequently entangled, the rhizoids produced from lower ends of all entangled cells; rhizoids frequently unilateral on each cell from base to mid-portion of plant, these cells commonly fragmenting and regenerating; upper thallus of turgid, cylindrical cells (sometimes cylindrical), (0.3)1-2 mm diam. Through the middle portions of thallus; terminal cells are often spherical; thalli are usually sterile, occasionally tetrasporangial; tetrasporangia without involucrate (fig. 2). Infrequently, saxicolous, or occasionally on sponges or holdfast of large brown algae, in isolated tufts, lower intertidal to subtidal (to 20m) (Abbot & Hollenberg, 1976). The data obtained by Garbary et al. (2004) suggest that this subtidal habitat of G. pacifica is based in part on lack of tolerance to UV radiation, and that UV protection mechanisms are not inducible or insufficient to prevent the accumulation of damage in this species.
Fig. 2. A tetrasporophyte thallus, tetraspores grouped forming a ring in the cells join. Scale bar= 20 µm
An interesting fact about this species is that it has been studied in many cell biology studies, such as cells elongation, cells regeneration, cell repair through cell fusion and type of growth (Duffield et al. 1972, Waaland & Cleland, 1974, Garbary et al. 2004).
Cytochemical data from the Ramus (1971) indicate that the plugs of Griffithsia pacifica (fig. 3) are composed of an acid polysaccharide-protein complex. He pointed out that the polysaccharide component is neither pectin nor cellulose, but contains both free sulfate and carboxyl groups, which is very characteristic of red algal polysaccharides. The protein component appears to contain basic amino acids. The plugs are acid resistant, but are soluble in weak alkali at high temperatures. As long as the plant remains vegetative, plug structure is never altered. However, during reproduction, especially the post-fertilization development of the female reproductive apparatus (cystocarp development), plugs in reproductive tissues and adjacent vegetative tissues break down and disappear. Subsequently, fusions occur between adjacent cells by dissolution of their common septum. The tissues thus formed appear to function in a “nursing” capacity (Kylin, 1956), facilitating the translocation of cytoplasmic materials to rapidly developing areas. The plug, then, appears to be a preformed “weakness” in the septum which is more labile to chemical or enzymatic degradation than the septum itself. Once the plug is removed, intercellular fusions and cytoplasimc translocations occur via the septal aperture with ease (Ramus 1971).
Fig. 3. The pit-plug of Griffithsia pacifica. Scale bar= 5 µm
The life history is triphasic isomorphic, with alternations of generations, but no differences between the morphology of the gametophytes and the tetrasporophytes. Also, a study regarding the life history of G. globurifera (as G. bornetiana) has described that the male plants are smaller than the female ones, and also is greater easy to find the tetrasporophytic rather than the gametophytic plants (Lewis 1909).
6. Literature Cited.
Abbott, I.A. & Hollenberg, G.J. (1976). Marine algae of California. Stanford, California: Stanford University Press.
Duffield, E.C.S., Waaland, S.D. & Cleland, R. (1972). Morphogenesis in the red alga, Griffithsia pacifica: regeneration from single cells. Planta 105: 185-195.
Guiry, M.D. & Guiry, G.M. 2013. AlgaeBase. World-wide electronic publication, National University of Ireland, Galway. http://www.algaebase.org; searched on 10 July 2013.
Lewis, I. F. 1909. The Life History of Griffithsia Bornetiana. Annals of Botany -23 (4): 639-690
Waaland, S.D. & Cleland, R.E. (1974). Cell repair through cell fusion in the red alga Griffithsia pacifica.Protoplasma 79: 185-196
Waaland, S.D., J.R. Waaland & R.E. Cleland. 1972. A new pattern of plant cell elongation: bipolar band growth. J. Cell Biol. 54:184-190.
7. Links to additional resources.
For molecular data available: http://www.ncbi.nlm.nih.gov/nuccore?cmd=search&term=Griffithsia+pacifica+%5Borganism%5D
More informations about Florideophyceae: http://tolweb.org/Florideophyceae
8. Page Authors & Affiliations.
Talita Vieira-Pinto, Ph.D. student, Instituto de Biociências, Universidade de São Paulo. Rua do Matão, travessa 14, nº 321, Cidade Universitária, São Paulo – SP, Brazil.