''Laminaria sinclairii'' is a

species A species () is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. It is the basic unit of Taxonomy (biology), ...

brown algae Brown algae (: alga) are a large group of multicellular algae comprising the class (biology), class Phaeophyceae. They include many seaweeds located in colder waters of the Northern Hemisphere. Brown algae are the major seaweeds of the temperate ...

(class Phaeophyceae), in the

family Family (from ) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). It forms the basis for social order. Ideally, families offer predictabili ...

Laminariaceae Laminariaceae is a Family (biology), family of brown algal seaweeds, many genera of which are popularly called "kelp". The table indicates the genera within this family. Guiry, M.D. & Guiry, G.M. (2006). AlgaeBase version 4.2. World-wide electron ...

. It is native to the lower intertidal zone of the northeastern Pacific Ocean from

British Columbia British Columbia is the westernmost Provinces and territories of Canada, province of Canada. Situated in the Pacific Northwest between the Pacific Ocean and the Rocky Mountains, the province has a diverse geography, with rugged landscapes that ...

southwards to

California California () is a U.S. state, state in the Western United States that lies on the West Coast of the United States, Pacific Coast. It borders Oregon to the north, Nevada and Arizona to the east, and shares Mexico–United States border, an ...

Description

This dark brown, perennial kelp grows from a creeping, branching

rhizome In botany and dendrology, a rhizome ( ) is a modified subterranean plant stem that sends out roots and Shoot (botany), shoots from its Node (botany), nodes. Rhizomes are also called creeping rootstalks or just rootstalks. Rhizomes develop from ...

which sends up

thalli Thallus (: thalli), from Latinized Greek (), meaning "a green shoot" or "twig", is the vegetative tissue of some organisms in diverse groups such as algae, fungi, some liverworts, lichens, and the Myxogastria. A thallus usually names the entir ...

at intervals. The thalli are ribbon-like and grow to a length of about and width of with a smooth surface and entire edges. They grow on short, cylindrical

stipes Crucifixion is a method of capital punishment in which the condemned is tied or nailed to a large wooden cross, beam or stake and left to hang until eventual death. It was used as a punishment by the Achaemenid Empire, Persians, Carthaginians, ...

some long and wide containing many

mucilage Mucilage is a thick gluey substance produced by nearly all plants and some microorganisms. These microorganisms include protists which use it for their locomotion, with the direction of their movement always opposite to that of the secretion of ...

ducts. It is very similar in appearance to '' Laminaria longipes'' but that species does not have mucilage glands in the stipes. In 1972, the American phycologist James W. Markham did some transplanting experiments to try to determine whether the presence of mucilage glands is a distinctive feature or the two species were identical. He found that they were indeed distinct and that there were some other differences between the two related to the width of blades, the shedding of the blades, the morphology of the reproductive structures, temperature tolerance and habitat preference.

Distribution and habitat

''Laminaria sinclairii'' is found in the northeastern Pacific Ocean, its range extending from

Vancouver Island Vancouver Island is an island in the northeastern Pacific Ocean and part of the Canadian province of British Columbia. The island is in length, in width at its widest point, and in total area, while are of land. The island is the largest ...

in British Columbia, southwards to

Ventura County, California Ventura County () is a County (United States), county located in Southern California, the southern part of the U.S. state of California. As of the 2020 United States census, 2020 census, the population was 843,843. The largest city is Oxnard, Ca ...

. It occurs on rocky substrates, sometimes partially covered in sand, in the lower part of the

intertidal zone The intertidal zone or foreshore is the area above water level at low tide and underwater at high tide; in other words, it is the part of the littoral zone within the tidal range. This area can include several types of habitats with various ...

Ecology

This is the dominant seaweed on rocks in the lower part of the intertidal zone in Oregon on beaches where sand levels fluctuate dramatically at different times of year. In March and April new thalli appear from the rhizomes but these blades are progressively buried by rising sand levels which results in the complete burial of the plants over the summer. With the arrival of storms in the fall, the sand is scoured away and the thalli reappear. Reproductive sori are produced on the old blades before they are shed in December and on the new blades that grow in the spring.

References

{{Taxonbar, from=Q3216746 Laminariaceae Biota of the Temperate Northern Pacific