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Ochrophyta, Phaeophyceae - brown seaweeds

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Egregia menziesii

Egregia menziesii (Turner) Areschoug
Phylum Ochrophyta, Class Phaeophyceae, Order Laminariales, Family Alariaceae

Long straplike thallus 2 cm wide with numerous proliferous blades and small gas-filled floats along opposite edges.

Abundant, low intertidal zone to subtidal, exposed & protected outer coast.

Geogr. Range: Alaska to Baja
Synonyms:
Similar species:

Image: Mazzaella flaccida (top rt., lower left), erect corallines (pink)

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Alaria marginata

Alaria marginata Postels & Ruprecht
Phylum Ochrophyta, Class Phaeophyceae, Order Laminariales, Family Alariaceae

Long bladelike thallus 15-30 cm wide, >2.5 m long, with slightly ruffled margin and a single obvious midrib.  Stipe at base of blade is short & cylindrical, bearing 20-40 lateral sporophyll blades (each 10-25 cm long).

Plants live only 1 year, recruiting in late winter or early spring; peak spore release is in mid to late autumn just prior to removal of thallus by winter storm waves.

Locally abundant, mid to low intertidal zone in California, on wave-exposed outer coast.

Geogr. Range: Alaska to Pt Conception, CA
Synonyms:
Similar species:

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Laminaria setchellii

Laminaria setchellii P.C. Silva
Phylum Ochrophyta, Class Phaeophyceae, Order Laminariales, Family Laminariaceae

Thallus with single stiff cylindrical stipe to 50 cm tall; stipe flattens at top and spreads into a single, deeply divided blade which is smooth and rubbery in texture.

Abundant, low intertidal zone to subtidal, exposed & protected outer coast.

Geogr. Range: Bering Strait to northern Baja
Synonyms: Laminaria dentigera
Similar species: Pterygophora and Eisenia are subtidal.

Image: Egregia across top & far right top.

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Postelsia palmaeformis

Postelsia palmaeformis Ruprecht
Phylum Ochrophyta, Class Phaeophyceae, Order Laminariales, Family Lessoniaceae

Thallus with single stiff cylindrical stipe to 60 cm tall; numerous flat corrugated blades; resembles a small palm tree.

Locally common, high to mid-intertidal zone often on mussel shells, very wave-exposed outer coast.

Geogr. Range: Vancouver Island to Morro Bay, central Calif.
Synonyms:
Similar species:

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Costaria costata  (C. Agardh) D.A. Saunders
Phylum Ochrophyta, Class Phaeophyceae, Order Laminariales, Family Laminariaceae

Thallus with single stipe giving rise to a single broad blade with 5 unevenly-spaced longitudinal ribs, to 35 cm wide &  50 cm long.

Moderately common, on rocks; low intertidal and shallow subtidal.

Geogr. Range: Alaska to southern California, also Japan
Synonyms:
Similar species:
Dictyoneuropsis / Dictyoneurum have multiple straplike blades; neither's blades have 5 distinct longitudinal ribs; both are more common subtidally.

Image: Laminaria setchellii (across top); Egregia menziesii (across bottom)

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Fucus gardneri

Fucus gardneri P.C. Silva
Phylum Ochrophyta, Class Phaeophyceae, Order Fucales, Family Fucaceae

Thallus to 25 cm tall, flattened dichotomous branches with midrib, 15-25 mm wide; olive-brown. Reproductive conceptacles concentrated at branch tips (swollen when mature).

Common, upper mid-intertidal zone, protected outer coast.

Geogr. Range: Washington to Pt. Conception
Synonyms: previously identified as Fucus distichus
Similar species:  Hesperophycus has conspicuous white hairs.

Image: Silvetia compressa (lower left)

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Hesperophycus californicus

Hesperophycus californicus P.C. Silva
Phylum Ochrophyta, Class Phaeophyceae, Order Fucales, Family Fucaceae

Thallus to 40 cm tall, flat with regular dichotomous branches 3-12 mm wide; conspicuous white hairs on either side of midrib; olive-green to yellow-brown.

Common, upper mid-intertidal zone, protected outer coast.

Geogr. Range: Santa Cruz, CA to Baja
Synonyms: Hesperophycus harveyanus
Similar species: Fucus gardneri lacks fine white hairs.

Image: Silvetia compressa (upper right)

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Silvetia compressa

Silvetia compressa (J.Agardh) Serrao et al.
Phylum Ochrophyta, Class Phaeophyceae, Order Fucales, Family Fucaceae

Thallus to 90 cm long, dichotomous branches 2-5 mm wide; subcylindrical with branch tips more compressed; dark olive-green to yellowish-brown.

Common, mid-intertidal zone, protected outer coast.

Geogr. Range: British Columbia to Baja
Synonyms: Pelvetia fastigiata, Fucus compressus
Similar species: Fucus & Hesperophycus have wider, more flattened thalli; Hesperophycus has white hairs.

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Analipus japonica

Analipus japonica (Harv.) Wynne
Phylum Ochrophyta, Class Phaeophyceae, Order Chordariales, Family Heterochordariaceae

Thallus to 35 cm long, main axes cylindrical, arising from crustose base with unbranched curved laterals which range from cylindrical to flattened.; dark brown to olive-tan.

Common but patchy, upper mid-intertidal zone, protected outer coast with moderate to strong wave action.

Geogr. Range: Alaska to Pt Conception
Synonyms:
Similar species:
superficially resembles a finely-branched Chondracanthus canaliculatus but its side branches surround main axis rather than being opposite as in Chondracanthus; much smaller & more delicate than Silvetia.

Image: eroded Mazzaella flaccida (upper left)

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