Best Subtidal

Nereocystis luetkeana, or bull kelp, is an annual brown kelp found along the Pacific coast of North America from Alaska to California. It has a long, whip-like stipe and a hollow gas-filled float from which ribbon-like blades extend, and it can reach about 36 m in length. The species forms dense sur...

Laminaria hyperborea, commonly known as Cuvie, is a species of large brown kelp found in the subtidal zones of the northeastern Atlantic Ocean. It grows up to 3.5 meters tall and forms dense canopy forests that provide critical habitat for a wide variety of marine life. This cold-water seaweed is di...

Egregia menziesii, commonly known as feather boa kelp, is a species of brown algae in the family Lessoniaceae. It is native to the rocky coastlines of the Pacific Ocean along western North America, ranging from Alaska to Baja California. The kelp is characterized by a single long, cylindrical stipe...

Cystoseira barbata is a large, canopy-forming brown macroalga in the family Sargassaceae. It is native to the shallow subtidal zones of the Mediterranean Sea and the Black Sea. The algae attach to rocky substrates using a holdfast and feature branched, bushy thalli with small air bladders that help...

Gelidium spinosum is a red alga in the family Gelidiaceae, found in the Mediterranean Sea and the eastern Atlantic Ocean. Species of the genus Gelidium are among the primary commercial sources of agar, a polysaccharide used as a gelling agent in food, microbiology, and various industrial application...

Lessonia corrugata is a species of subantarctic brown macroalgae, or kelp, native to the southern coasts of South America and adjacent islands. It thrives in cold-water marine environments, forming dense subtidal forests that provide critical habitat and shelter for diverse marine communities. The a...

Phyllospora comosa, commonly known as crayweed, is a large brown macroalga endemic to the shallow coastal waters of southeastern Australia. The seaweed forms dense underwater canopies on rocky reefs, providing vital habitat and food sources for marine life, including rock lobsters. Crayweed populati...

Pterygophora californica, commonly known as stalked kelp, is a perennial brown macroalga native to the rocky subtidal zones of the Pacific North American coast. The seaweed features a single, woody central stipe that supports long, flat blades, structurally resembling an underwater palm tree. Growth...

Pterocladia lucida is a species of red macroalgae belonging to the family Gelidiaceae. It is distributed across the Southern Hemisphere, particularly along the coastlines of New Zealand and southern Australia. The species grows in subtidal zones and is characterized by its flattened, cartilaginous b...

Sarcothalia crispata is a species of red macroalgae in the order Gigartinales, native to the southeastern Pacific coast. It is distributed along the coastlines of Peru and southern Chile, where it grows in subtidal marine environments. The species is harvested for its cell wall polysaccharides, whic...

Eualaria fistulosa, commonly known as dragon kelp, is a large brown macroalga belonging to the order Laminariales. It is native to the North Pacific, with a range extending from Alaska down the Aleutian Islands to the coastlines of Russia and Japan. The species is structurally distinct, featuring a...

Halidrys siliquosa, commonly known as sea oak, is a species of brown macroalgae primarily found in the northeastern Atlantic Ocean and the Mediterranean Sea. It is easily identified by its branched fronds, which feature segmented, pod-like pneumatocysts that closely resemble seed pods. These air-fil...

Solieria chordalis is a species of red marine alga belonging to the family Solieriaceae. It is distributed along the Atlantic and Mediterranean coasts, where it typically inhabits shallow subtidal waters. The seaweed is characterized by its gelatinous, cord-like thallus and is harvested on a commerc...

Saccharina groenlandica is a species of brown kelp belonging to the family Laminariaceae, native to the cold, nutrient-rich marine waters of the Arctic and subarctic regions, particularly around Greenland. Like other species in its genus, it is a large, macroscopic alga adapted to subtidal rocky env...

Desmarestia aculeata, commonly known as sea sorrel, is a species of brown algae found in cold-water marine environments across the North Atlantic and Pacific Oceans. It is notable for its ability to accumulate sulfuric acid within its cellular vacuoles. This acidic content can rapidly destroy other...

Laminaria setchellii is a species of brown kelp belonging to the family Laminariaceae, native to the Pacific coast of North America. It grows in low intertidal and shallow subtidal zones, where it attaches firmly to rocky substrates using a robust holdfast. The species is characterized by a long, st...

The graceful decorator crab (Oregonia gracilis) is a marine crustacean found along the Pacific coast of North America, ranging from the Bering Sea to central California. It is a member of the spider crab group, characterized by a small triangular carapace and long, slender walking legs. Like other d...

Desmarestia viridis is a species of brown algae native to temperate and polar coastal waters. It is distinguished by its unique ability to store high concentrations of sulfuric acid within its cellular vacuoles. When the alga's cells are disrupted or damaged, the released acid causes its tissues to...

Red alga native to the Atlantic coast of North America and the Caribbean, studied for its carrageenan-like sulfated polysaccharides with potential commercial applications.

Delicate rose-colored red alga of the Atlantic and Mediterranean, classified in the order Halymeniales and notable for its thin, fan-shaped fronds.

A large brown kelp (Laminariaceae) forming extensive subtidal forests along the cold upwelling coasts of South Africa and Namibia, reaching several meters in length on rocky reefs.

Iridescent red alga of Pacific North American rocky shores, distinguished by violet-tinged blades bearing branching, vein-like midribs.

Red alga (Halymeniales) native to Australian waters, belonging to a large pantropical genus widely used as a food source and investigated for bioactive compounds.

Cymathaere triplicata is a Pacific North American brown alga (Laminariaceae) recognized by its blade bearing three prominent longitudinal ribs, hence the specific epithet triplicata.

*Ecklonia radiata* is a dominant habitat-forming seaweed found in the temperate reefs of Australia and New Zealand, supporting diverse marine ecosystems and biodiversity.

*Laminaria hyperborea* is a large brown macroalga that forms extensive kelp forests in the Northeast Atlantic and is heavily harvested in Norway for alginate production.

Red alga (Halymeniaceae) native to the Pacific coast of North America, distinguished by a conspicuously net-like reticulate blade formed by anastomosing veins.

Red alga (Delesseriaceae) found on the Pacific coast of North America and in the Mediterranean, notable for its strap-like blade bearing an interrupted midrib.

Rytiphlaea tinctoria is a red alga (Rhodomelaceae) of the Mediterranean and Atlantic, historically used to produce a reddish-purple dye extracted from its thalli in southern Europe.