| KEY TO GENERA AND SPECIES OF BROWN ALGAE | ||
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CONTENTS
FIGURES ABOUT INDEXES: Reds · Greens · Browns KEYS: Browns |
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| 1 | Thallus appears filamentous | 2 | |
| 1 | Thallus other than a simple filament | 23 | |
| & lt; | < a name="2"> 2 | Thallus wholly or partly endophytic | 3 |
| 2 | Thallus free-living or epiphytic | 6 | |
| & lt; | 3 | Branching at right angles; multiseriate at maturity; host the epiphytic red alga Smithora | Internoretia fryeana |
| 3 | Branching at oblique angles; uniseriate throughout | 4 | |
| & lt; | 4 | Lifting the surface of Hedophyllum , often erupting through the epidermis | Gononema aecidioides |
| 4 | Filaments among the bases of the unangia in other laminarians | 5 | |
| & lt; | 5 | Host is Laminaria setchellii | Streblonema evagatum |
| 5 | Host is Alaria | Streblonema pacificum | |
| & lt; | 6 | Thallus multiseriate and parenchymatous in part, though appearing filamentous | 7 |
| 6 | Thallus truly filamentous in structure | 8 | |
| & lt; | 7 | Multseriate thallus behind a large and distinctive apical cell | Sphacelaria ( see genus key ) |
| 7 | Multiseriate thallus behind an intercalary meristem that produces a uniseriate terminal filament | Stictyosiphon tortilis | |
| & lt; | 8 | Hooked branchlets unite upright branches in yarn-like strands, on fucoids | Spongonema tomentosum |
| 8 | Branches generally free or absent | 9 | |
| & lt; | 9 | Reproductive organs intercalary | 10 |
| 9 | Reproductive organs not intercalary | 13 | |
| & lt; | 10 | Minute epiphyte on Postelsia stipes; plurangia in axes and in paired, opposite branches | Pilayella gardneri |
| 10 | On various substrates; organs in catenate series | 11 | |
| & lt; | 11 | Unbranched | 12 |
| 11 | Branched | Pilayella littoralis | |
| & lt; | 12 | Reproductive organs large and globose, not in adjacent series | Leptonematella fasciculata |
| 12 | Unangia in series below series of plurangia, to the tip of the filament | Pilayella tenella | |
| & lt; | 13 | Minute, epiphyte on Fucus , unangia borne laterally near filament base | Elachista fucicola |
| 13 | On various substrates, plurangia common | 14 | |
| & lt; | 14 | Discoid base | 15 |
| 14 | Filaments attached at the base by rhizoids or a short prostrate filament | 19 | |
| & lt; | 15 | Basal disc distromatic in part | 16 |
| 15 | Basal disc monostromatic | 17 | |
| & lt; | 16 | Small ( < 2 mm ) discs on the blades of laminarians | Hecatonema primarium |
| 16 | Circular or irregular cushions ( to 10 mm ), often confluent | Hecatonema streblonematoides | |
| & lt; | 17 | Short unbranched or sparingly branched uprights. | Myrionema ( see genus key ) |
| 17 | Dense mat of unbranched upright filaments | 18 | |
| & lt; | 18 | Erect filaments 10 - 12 µ m in diameter, on Nereocystis | Compsonema serpens |
| 18 | Erect filaments 8 - 9 µ m in diameter, on large algae | Compsonema fructuosum | |
| & lt; | 19 | Meristem at the base of branches, above which no lateral branching occurs | 22 |
| 19 | Meristem inconspicuous and diffuse | 20 | |
| & lt; | 20 | Plurangia on short lateral branches, growth intercalary | Ectocarpus ( see genus key ) |
| 20 | Plurangia sessile, generally asymmetrical, meristems inconspicuous | 21 | |
| & lt; | 21 | Plurangia arranged in unilateral series on axes | Hincksia sandriana |
| 21 | Plurangia irregularly arranged, mostly singly | Hincksia granulosa | |
| & lt; | 22 | Plurangia irregularly conical, tapering sharply to tip | Feldmannia irregularis |
| 22 | Plurangia cylindrical, thin, and blunt tipped | Feldmannia simplex | |
| & lt; | 23 | Thallus robust and evidently parenchymatous | 24 |
| 23 | Thallus appears cylindrical, globose, saccate, or crustose | 57 | |
| & lt; | 24 | Thallus with distinct blades and hapteran holdfast separated by a stipe | 25 |
| 24 | Thallus parenchymatous or pseudparenchymatous, stipe insubstantial or absent | 44 | |
| & lt; | 25 | Thallus with differentiated sporophylls and vegetative blades | 26 |
| 25 | Thallus in which all blades are sporophyllous or which bear conceptacles | 31 | |
| & lt; | 26 | Sporophylls borne laterally on stipe, below a single vegetative blade | 27 |
| 26 | Sporophylls borne otherwise | 28 | |
| & lt; | 27 | Teminal blade with conspicuous midrib, lamina thin, stipe flexible | Alaria ( see genus key ) |
| 27 | Terminal blades smooth, lamina tough and leathery, stipe stiff and woody | Pterygophora californica | |
| & lt; | 28 | Blades formed in terminal dichotomies, without pneumatocysts | Lessoniopsis littoralis |
| 28 | Blades with basal pneumatocysts formed laterally | 29 | |
| & lt; | 29 | Sporophylls and vegetative blades profuse along a flattened rachis | Egregia menziesii |
| 29 | Blades regularly spaced on long, cylindrical branches | 30 | |
| & lt; | 30 | Blades and pneumatocysts small and densely packed | Sargassum muticum |
| 30 | Blades and pneumatocysts large and well spaced | Macrocystis integrifolia | |
| & lt; | 31 | Stipe prostrate with haptera growing from sides | 32 |
| 31 | Stipe upright | 33 | |
| & lt; | 32 | Blades branching by splitting from the base to the tip; no midrib | Dictyoneurum californicum |
| 32 | Blades unbranched; distinct midrib | Dictyoneuropsis reticulata | |
| & lt; | 33 | Stipe branched | 34 |
| 33 | Stipe unbranched, terete or flat but not blade-like | 36 | |
| & lt; | 34 | Stipe flattened near base; seasonally terete near tip, bearing pneumatocysts and conceptacles | 35 |
| 34 | Stipe appears dichotomously and repeatedly branched near tip | Eisenia arborea | |
| & lt; | 35 | Pneumatocysts in catenate series | Cystoseira osmundacea |
| 35 | Pneumatocysts in pairs | Cystoseira geminata | |
| & lt; | 36 | Blades with one or more midribs | 37 |
| 36 | Blades without a percurrent rib | 41 | |
| & lt; | 37 | Blades with multiple percurrent midribs, bullations common | 38 |
| 37 | Blade with a single midrib | 39 | |
| & lt; | 38 | Blade with five longitudinal ribs | Costaria costata |
| 38 | Blade with three longitudinal ribs | Cymathere triplicata | |
| & lt; | 39 | Blade about as wide as long, bullate, frequently perforated | 40 |
| 39 | Blade longer than wide, bullations along midrib | Pleurophycus gardneri | |
| & lt; | 40 | Stipe cylindrical, not fimbriate; blade with two basal scrolls | Agarum fimbriatum |
| 40 | Stipe flattened, with fimbriate margins; blade base rounded or cordate | Agarum clathratum | |
| & lt; | 41 | Blades smooth, without notable bullations, ridges, or perforations | Laminaria ( see genus key ) |
| 41 | Blades ornamented with bullations, ridges, or perforations | 42 | |
| & lt; | 42 | Stipe solid topped with a single blade | Laminaria ( see genus key ) |
| 42 | Stipe hollow, several ridged blades | 43 | |
| & lt; | 43 | Stipe terminates in a bulbous pneumatocyst and numerous lamina | Nereocystis luetkeana |
| 43 | Stipe narrows towards the tip and lamina | Postelsia palmaeformis | |
| & lt; | 44 | Thallus a thin blade | 53 |
| 44 | Thallus coarse and strong | 45 | |
| & lt; | 45 | Thallus a broad blade ( frequently with falcate splits ), haptera arise from blade edge | Hedophyllum sessile |
| 45 | Thallus other | 46 | |
| & lt; | 46 | Thallus roughly terete | 47 |
| 46 | Thallus strap-like, dichotomously branched; discoid holdfast | 49 | |
| & lt; | 47 | Thallus unbranched or pinnately branched; strong discoid holdfast; acidulous | Desmarestia ( see genus key ) |
| 47 | With numerous irregular branches | 48 | |
| & lt; | 48 | Arising from crustose base; branches straight or tapering | Analipus japonicus |
| 48 | Small discoid holdfast; some branches clavate and blunt | Saundersella simplex | |
| & lt; | 49 | Thallus with a midrib and well defined terminal receptacles | 50 |
| 49 | Thallus narrow, without evident midrib; receptacles poorly defined | 52 | |
| & lt; | 50 | Thallus with pits in parallel rows along the midrib | Hesperophycus californicus |
| 50 | Thallus without rows of pits | 51 | |
| & lt; | 51 | Midrib and oval conceptacle sharply defined from blade | Fucus spiralis |
| 51 | Midrib and elongated conceptacle grade into blade | Fucus gardneri | |
| & lt; | 52 | Dichotomies often unequal; two eggs in each oogonium | Silvetia compressa |
| 52 | Dichotomies generally equal; one egg and a polar body in each oogonium | Pelvetiopsis limitata | |
| & lt; | 53 | Thallus epiphytic | 58 |
| 53 | Growing on rocks, shells, or other inanimate substrate | 54 | |
| & lt; | 54 | Thallus a branched cylinder, extremely lax, lubricous, and covered with fine hairs | Haplogloia andersonii |
| 54 | Thallus other | 55 | |
| & lt; | 55 | Thallus flattened | 56 |
| 55 | Thallus tubular, irregular, globose, saccate, or crustose | 61 | |
| & lt; | 56 | Blade fan-like, splitting into more narrow blades; thallus less than five cm high | Syringoderma abyssicola |
| 56 | Blade not fan-like, edges irregular or roughly parallel | 57 | |
| & lt; | 57 | Blade shape very irregular; growth from a perennial basal crust | Phaeostrophion irregulare |
| 57 | Blades mildly flabellate but not fan-like; to twenty cm or more when mature | Dictyota binghamiae | |
| & lt; | 58 | Thallus epiphytic on Egregia | Halorhipis winstonii |
| 58 | Thallus epiphytic on sea grasses, occasionally on algae other than Egregia | 59 | |
| & lt; | 59 | Medullary cells four to five times the diameter of cortical cells | Petalonia fascia |
| 59 | Medullary cells two to three times the diameter of cortical cells | 60 | |
| & lt; | 60 | Thalli to 2. 5 cm; margins plane | Punctaria hesperia |
| 60 | Thalli to 20 cm; margins ruffled | Punctaria occidentalis | |
| & lt; | 61 | Thallus hollow | 62 |
| 61 | Thalli crustose, not hollow | 70 | |
| & lt; | 62 | Thalli hollow but not distinctly tubular | 65 |
| 62 | Clumps of tubular thalli found in high intertidal pools | 63 | |
| & lt; | 63 | Mature branches with spiral grooves creating a coiled appearance | Melanosiphon intestinalis |
| 63 | Mature branches not spirally grooved | 64 | |
| & lt; | 64 | Mature branches with regular constrictions; senescent blades up to one cm wide | Scytosiphon lomentaria |
| 64 | Mature branches without regular constrictions; seldom more than 0. 4 cm wide | Scytosiphon dotyi | |
| & lt; | 65 | Irregular, sub-spherical, or globose forms | 68 |
| 65 | Thalli saccate | 66 | |
| & lt; | 66 | Sori numerous and distinct; epiphytic solely on the red algae Neorhodomela and Odonthalia | Soranthera ulvoidea |
| 66 | Sori not obvious; on rocks or epiphytic | 67 | |
| & lt; | 67 | Epiphytic on Cystoseira and other brown algae | Coilodesme californica |
| 67 | On rocks in the low intertidal and subtidal | Coilodesme bulligera | |
| & lt; | 68 | Convoluted, globose forms; epiphytic, but often appearing saxicolous; smears when crushed | Leathesia difformis |
| 68 | Sacs with thin but strong walls that tear but do not crush | 69 | |
| & lt; | 69 | Dimpled, sub-spherical sacs, commonly epiphytic | Colpomenia peregrina |
| 69 | Finger like sacs, appear saxicolous but often epiphytic on crustose algae | Colpomenia bullosa | |
| & lt; | 70 | Crust pulvinate, rugose, and spongy; frequently spreading | Petrospongium rugosum |
| 70 | Crust smooth and firm | 71 | |
| & lt; | 71 | Crustose thallus composed of tightly adherent upright filaments | Ralfsia ( see genus key ) |
| 71 | Crustose thallus composed of packed but not adherent filaments | Petroderma maculiforme | |
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