The Rhodophyta is a unique group of organisms, which, like the Chlorophyta, are thought to be very ancient. Most red algae belong to the class Florideophyceae, which is characterized by proteinaceous "pit" plugs occluding the connection between cells (due to incomplete cell cleavage at mitosis). Most red algae are multicellular and marine, but unicellular and freshwater taxa also occur. No red algal cell, including reproductive cells, is flagellated.
Like the Chlorophyta, the chloroplast is encircled by a double membrane, but thylakoids occur singly and are not stacked. The primary pigment is chlorophyll a, and cells are distinctively colored by the accessory pigments, phycocyanin and phycoerythrin, which occur in hemispheric granules on the thylakoids. The photosynthetic product is a highly branched form of starch and is stored outside the chloroplast.
Phylum: Rhodophyta
Class: Bangiophyceae
Order: Bangiales
Family: Bangiaceae
- "Bangia" spp. Black sea-hair
- Boreophyllum aestivale (S.C.Lindstrom & Fredericq) S.C.Lindstrom Summer laver
- Fuscifolium papenfussii (V.Krishnamurthy) S.C.Lindstrom Eastern dark laver
- Fuscifolium tasa (Yendo) S.C.Lindstrom Western dark laver
- Pyropia abbottiae (V.Krishnamurthy) S.C.Lindstrom Black seaweed
- Pyropia fallax (S.C.Lindstrom & K.M.Cole) S.C.Lindstrom False laver
- Pyropia fucicola (V.Krishnamurthy) S.C.Lindstrom Rockweed laver
- Pyropia gardneri (G.M.Smith & Hollenberg) S.C.Lindstrom Kelp laver
- Pyropia nereocystis (C.L.Anderson) S.C.Lindstrom Bull Kelp laver
- Pyropia perforata (J.Agardh) S.C.Lindstrom Purple laver
- Pyropia pseudolanceolata (V.Krishnamurthy) S.C.Lindstrom Olive green winter laver
- Pyropia taeniata S.C.Lindstrom Long laver
- Wildemania amplissima (Kjellman) Foslie Red cellophane
- Wildemania norrisii (V.Krishnamurthy) S.C.Lindstrom Norris' laver
- Wildemania variegata (Kjellman) De Toni Kjellman's laver
Class: Compsopogonophyceae
Order: Erythropeltidales
Family: Erythrotrichiaceae
- Smithora naiadum (C.L.Anderson) Hollenberg Seagrass laver
Class: Florideophyceae
Order: Acrochaetiales
Family: Rhodochortonaceae
- Rhodochorton purpureum (Lightfoot) Rosenvinge Red sea moss
Order: Ahnfeltiales
Family: Ahnfeltiaceae
- Ahnfeltia fastigiata (Endlicher) Makienko Bushy ahnfelt's seaweed
Order: Bangiales
Family: Bangiaceae
- Pyropia kurogii (S.C.Lindstrom) S.C.Lindstrom Split spring laver
- Pyropia torta (V.Krishnamurthy) S.C.Lindstrom Teal nori
- Pyropia unabbottiae S.C.Lindstrom False black seaweed
Order: Bonnemaisoniales
Family: Bonnemaisoniaceae
- Pleuroblepharidella japonica (Okamura) M.J.Wynne False sea brush
Order: Ceramiales
Family: Callithamniaceae
- Callithamnion pikeanum Harvey Beauty bush
Family: Ceramiaceae
- Antithamnion defectum Kylin Dwarf skein
- Antithamnionella pacifica (Harvey) E.M.Wollaston Hooked skein
- Ceramothamnion pacificum (Collins) M.J.Wynne & C.W.Schneider Staghorn felt
- Herpochondria borealis (Ruprecht) Barros-Barreto & Maggs Coarse sea lace
- Scagelia occidentalis (Kylin) E.M.Wollaston Scagel's skein
Family: Delesseriaceae
- Cryptopleura ruprechtiana (J.Agardh) Kylin Hidden rib
- Cumathamnion decipiens (J.Agardh) M.J.Wynne & G.W.Saunders Winged rib
- Loranthophycus sp. Red feathered seaweed
- Membranoptera spinulosa (Ruprecht) Kuntze Bering membrane wing
- Mikamiella ruprechtiana (Zinova) M.J.Wynne Mikami's sea oak
- Nienburgia sp. prolifera M.J.Wynne Northern toothed wing
- Phycodrys fimbriata (Kuntze) Kylin Common sea oak
- Polyneura latissima (Harvey) Kylin Crisscross network
- Tokidadendron bullatum (N.L.Gardner) M.J.Wynne Northern sea oak
Family: Rhodomelaceae
- Neorhodomela aculeata (Perestenko) Masuda Graceful black pine
- Neorhodomela larix (Turner) Masuda Black pine
- Neorhodomela oregona (Doty) Masuda Oregon pine
- Odonthalia comosa (Setchell & N.L.Gardner) G.W.Saunders & C.W.Schneider Rockweed brush
- Odonthalia floccosa (Esper) Falkenberg Sea brush
- Odonthalia kamtschatica (Ruprecht) J.Agardh Flattened sea brush
- Odonthalia setacea (Ruprecht) Perestenko Russian sea brush
- Osmundea spectabilis (Postels & Ruprecht) K.W.Nam Sea laurel
- Polysiphonia pacifica var. pacifica Hollenberg Pretty polly
- Savoiea bipinnata (Postels & Ruprecht) M.J.Wynne Black tassel
- Savoiea hamata (E.S.Zinova) M.J.Wynne Subtidal tassel
Family: Wrangeliaceae
- Pleonosporium vancouverianum (J.Agardh) Setchell & N.L.Gardner Alternate skein
- Ptilota asplenioides (Esper) C.Agardh Sea fern
- Ptilota serrata Kützing Northern sea fern
- Tokidaea chilkatensis S.C.Lindstrom & M.J.Wynne Tokida's red felted skein
Order: Corallinales
Family: Corallinaceae
- Bossiella frondescens (Postels & Ruprecht) E.Y.Dawson Enigmatic coral seaweed
- Corallina officinalis Linnaeus Chalky coral seaweed
- Corallina vancouveriensis Yendo Graceful coral seaweed
- Johansenia macmillanii (Yendo) K.R.Hind & G.W.Saunders Macmillan's coral seaweed
Order: Corallinales & Hapalidiales
Family: Corallinaceae & Hapalidiaceae
- Coralline crusts Calcareous crusts
Order: Gigartinales
Family: Dumontiaceae
- Constantinea rosa-marina (S.G.Gmelin) Postels & Ruprecht Cup and saucer
- Constantinea simplex Setchell Simple saucer
- Constantinea subulifera Setchell Cracked saucer
- Cryptosiphonia woodii (J.Agardh) J.Agardh Bleached brunette
- Dilsea californica (J.Agardh) Kuntze California red blade
- Dumontia alaskana V.Tai, S.C.Lindstrom & G.W.Saunders Purple pencils
- Dumontia simplex Cotton Ephemeral spring tubes
- Farlowia mollis (Harvey & Bailey) Farlow & Setchell Farlow's seaweed
- Neodilsea borealis (I.A.Abbott) S.C.Lindstrom Northern red blade
Family: Endocladiaceae
- Endocladia muricata (Endlicher) J.Agardh Black sea moss
- Gloiopeltis furcata (Postels & Ruprecht) J.Agardh Jelly moss
Family: Furcellariaceae
- Opuntiella californica (Farlow) Kylin Red Opuntia
- Turnerella mertensiana (Postels & Ruprecht) F.Schmitz Red sea-cabbage
Family: Gigartinaceae
- Chondracanthus exasperatus (Harvey & Bailey) Hughey Turkish towel
- Mazzaella parksii (Setchell & N.L.Gardner) Hughey, P.C.Silva & Hommersand Iridescent horn-of-plenty
- Mazzaella parvula (Kjellmann) P.W.Gabrielson, S.C.Lindstrom, Hughey & Hammersand Small northern mazza weed
- Mazzaella phyllocarpa (Postels & Ruprecht) Perestenko Northern mazza weed
- Mazzaella splendens (Setchell & N.L. Gardner) Fredericq Splendid iridescent seaweed
Family: Gloiosiphoniaceae
- Gloiosiphonia capillaris (Hudson) Carmichael Red capillary seaweed
Family: Kallymeniaceae
- Callophyllis spp. Red Sea fan
- Euthora cristata (C.Agardh) J.Agardh Delicate northern sea fan
- Hommersandia maximicarpa G.I.Hansen & S.C.Lindstrom Hommersand's seaweed
- Kallymeniopsis spp. Russian red blade
Family: Nemaliaceae
- Dudresnaya sp. False soft coral
Family: Phyllophoraceae
- Coccotylus truncatus (Pallas) M.J.Wynne & J.N.Heine Arctic false Opuntiella
- Mastocarpus alaskensis S.C.Lindstrom, Hughey & Martone Turkish washcloth
- Mastocarpus latissimus (Harvey) S.C.Lindstrom, Hughey & Martone Harvey's Turkish washcloth
- Mastocarpus pacificus (Kjellman) Perestenko Northern Turkish washcloth
- Mastocarpus rigidus S.C.Lindstrom, Hughey & Martone Narrow Turkish washcloth
- Mastocarpus spp. (Petrocelis phase) Tar spot alga
Family: Solieriaceae
- Sarcodiotheca gaudichaudii (Montagne) P.W.Gabrielson False sea spaghetti
Order: Halymeniales
Family: Halymeniaceae
- Grateloupia californica Kylin Spiny red bottlebrush
- Prionitis sternbergii (C.Agardh) J.Agardh Bleachweed
Order: Hapalidiales
Family: Hapalidiaceae
- Boreolithothamnion soriferum (Kjellman) P.W.Gabrielson, Maneveldt, Hughey & V.Peña Rhodoliths
- Clathromorphum nereostratum Lebednik Thick rock crust
- Neopolyporolithon articum (Kjellman) P.W.Gabrielson, S.C.Lindstrom & Hughey Arctic coralline crust
- Neopolyporolithon reclinatum (Foslie) W.H.Adey & H.W.Johansen Coralline disc
Order: Hildenbrandiales
Family: Hildenbrandiaceae
- Hildenbrandia rubra (Sommerfelt) Meneghini Rusty rock
Order: Nemaliales
Family: Nemaliaceae
- Nemalion sp. Rubber threads
Order: Nemastomatales
Family: Schizymeniaceae
- Schizymenia pacifica (Kylin) Kylin Slippery red blade
Order: Palmariales
Family: Palmariaceae
- Devaleraea callophylloides (M.W.Hawkes & Scagel) G.W.Saunders, C.J.Jackson & Salomaki Frilly red ribbon
- Devaleraea firma (Postels & Ruprecht) Selivanova Flattened sea sac
- Devaleraea mollis (Setchell & N.L.Gardner) G.W.Saunders, C.J.Jackson & Salomaki Red ribbon
- Halosaccion fucicola Postels & Ruprecht Sea sac
- Halosaccion glandiforme (S.G.Gmelin) Ruprecht High intertidal sea sac
- Halosaccion sp. undesribed Ephemeral sea sac
- Palmaria hecatensis M.W.Hawkes Stiff red ribbon
- Palmaria sp. Alaskan False Dulse
Order: Plocamiales
Family: Plocamiaceae
- Plocamium pacificum Kylin Sea comb
Order: Rhodymeniales
Family: Rhodymeniaceae
- Lukinea dissecta Perestenko Northern fan
- Sparlingia pertusa (Postels & Ruprecht) G.W.Saunders, I.M.Strachan & Kraft Red eyelet silk
corallines
tubes or sacs
finely branched
coarsely branched
thin blades
thick blades
blades with ribs or veins
other forms
No species match .