''Chondracanthus exasperatus'', commonly called Turkish towel, is a species of

seaweed Seaweed, or macroalgae, refers to thousands of species of macroscopic, multicellular, marine algae. The term includes some types of '' Rhodophyta'' (red), ''Phaeophyta'' (brown) and ''Chlorophyta'' (green) macroalgae. Seaweed species such as ...

in the family

Gigartinaceae Gigartinaceae is a red algae family in the order Gigartinales. Genera Genera in the family Gigartinaceae include: *'' Chondracanthus'' Kützing, 1843 *''Chondrus'' Stackhouse, 1797 *'' Gigartina'' Stackhouse, 1809 *'' Iridaea'' Bory de Sain ...

. The

specific epithet In taxonomy, binomial nomenclature ("two-term naming system"), also called nomenclature ("two-name naming system") or binary nomenclature, is a formal system of naming species of living things by giving each a name composed of two parts, bot ...

' ( lit. 'roughened') refers to the bumpy texture of the blades (leaf-like structures). This texture also leads to the common name which evokes the luxurious feel of a

towel A towel is a piece of absorbent cloth or paper used for drying or wiping a surface. Towels draw moisture through direct contact. In households, several types of towels are used, such as hand towels, bath towels, and kitchen towels. Paper towels ...

from a

Turkish bath A hammam ( ar, حمّام, translit=ḥammām, tr, hamam) or Turkish bath is a type of steam bath or a place of public bathing associated with the Islamic world. It is a prominent feature in the culture of the Muslim world and was inherited ...

. The rough, papillae-strewn blade surface even makes it difficult to measure the temperature using

infrared thermometer An infrared thermometer is a thermometer which infers temperature from a portion of the thermal radiation sometimes called black-body radiation emitted by the object being measured. They are sometimes called laser thermometers as a laser is use ...

Description

It is a perennial species. Like many species in

, the appearance of ''C. exasperatus'' can vary depending upon grown conditions. It can be confused with '' Chondracanthus spinosus'' and '' Gigartina binghamiae'', and it might take RFLP analysis to be sure of the species. In addition, the names of the species in the genera '' Gigartina'' and '' Chondracanthus'' have been adjusted several times since 1961. It is also similar to '' Mastocarpus'' species, known as Turkish washcloths, but is smaller, with branched blades. The

leaf margin A leaf ( : leaves) is any of the principal appendages of a vascular plant stem, usually borne laterally aboveground and specialized for photosynthesis. Leaves are collectively called foliage, as in "autumn foliage", while the leaves, ste ...

s of the blades are smooth in cooler water and then become toothed and jagged as the temperature increases. In more exposed areas, the blades are thicker. Increased water velocity will cause the blades to change shape. The color of the thallus is greenish when exposed to

ultraviolet Ultraviolet (UV) is a form of electromagnetic radiation with wavelength from 10 nanometer, nm (with a corresponding frequency around 30 Hertz, PHz) to 400 nm (750 Hertz, THz), shorter than that of visible light, but longer than ...

light, but when it grows in deeper water it is darker red to purple. Though it prefers lower water temperatures it can grow at 25 °C, but ends up dark red to black in color and having flat or cylindrical branch clusters. As originally described, ''C. exasperatus'' has a leafy stipe, with large long leathery-membranaceous blades that are

lanceolate The following is a list of terms which are used to describe leaf morphology in the description and taxonomy of plants. Leaves may be simple (a single leaf blade or lamina) or compound (with several leaflets). The edge of the leaf may be regular o ...

and

simple Simple or SIMPLE may refer to: *Simplicity, the state or quality of being simple Arts and entertainment * ''Simple'' (album), by Andy Yorke, 2008, and its title track * "Simple" (Florida Georgia Line song), 2018 * "Simple", a song by Johnn ...

. The blade, and the majority of the thallus, is purplish-red. Blade margins are thick, with rounded teeth, and

appendiculate This glossary of botanical terms is a list of definitions of terms and concepts relevant to botany and plants in general. Terms of plant morphology are included here as well as at the more specific Glossary of plant morphology and Glossary o ...

. The

thallus Thallus (plural: 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. Many of these organisms wer ...

has simple, ramenta-like spiny projections (papillae) thickly strewn on both sides. Coccoid

pedicels In botany, a pedicel is a stem that attaches a single flower to the inflorescence. Such inflorescences are described as ''pedicellate''. Description Pedicel refers to a structure connecting a single flower to its inflorescence. In the absenc ...

are in marginal spines emerging from the thallus. ''C. exasperatus'' grows the fastest in the summer and slowest near the

winter solstice The winter solstice, also called the hibernal solstice, occurs when either of Earth's poles reaches its maximum tilt away from the Sun. This happens twice yearly, once in each hemisphere ( Northern and Southern). For that hemisphere, the winte ...

. Thalli have a moisture content of about 81.4% and

protein Proteins are large biomolecules and macromolecules that comprise one or more long chains of amino acid residues. Proteins perform a vast array of functions within organisms, including catalysing metabolic reactions, DNA replication, respo ...

content of 1.59-1.97%.

Distribution and habitat

''C. exasperatus'' is found on the

Pacific coast Pacific coast may be used to reference any coastline that borders the Pacific Ocean. Geography Americas Countries on the western side of the Americas have a Pacific coast as their western or southwestern border, except for Panama, where the Pac ...

North America North America is a continent in the Northern Hemisphere and almost entirely within the Western Hemisphere. It is bordered to the north by the Arctic Ocean, to the east by the Atlantic Ocean, to the southeast by South America and the Car ...

from

Baja California Baja California (; 'Lower California'), officially the Free and Sovereign State of Baja California ( es, Estado Libre y Soberano de Baja California), is a state in Mexico. It is the northernmost and westernmost of the 32 federal entities of Mex ...

north to

Sitka Sound Sitka Sound is a body of water near the city of Sitka, Alaska. It is bordered by Baranof Island to the south and the northeast, by Kruzof Island to the northwest and by the Pacific Ocean to the southwest. During the early 19th century it was a ...

. The type locality is in

Puget Sound Puget Sound ( ) is a sound of the Pacific Northwest, an inlet of the Pacific Ocean, and part of the Salish Sea. It is located along the northwestern coast of the U.S. state of Washington. It is a complex estuarine system of interconnected ma ...

opposite

Fort Nisqually Fort Nisqually was an important fur trading and farming post of the Hudson's Bay Company in the Puget Sound area, part of the Hudson's Bay Company's Columbia Department. It was located in what is now DuPont, Washington. Today it is a living hist ...

. It grows on rocks in semi-exposed or semi-protected areas of the upper subtidal to lower

intertidal zone The intertidal zone, also known as the foreshore, is the area above water level at low tide and underwater at high tide (in other words, the area within the tidal range). This area can include several types of habitats with various species o ...

, down to a depth of 20m.

Ecology

Proliferation of

invasive species An invasive species otherwise known as an alien is an introduced organism that becomes overpopulated and harms its new environment. Although most introduced species are neutral or beneficial with respect to other species, invasive species ad ...

such as '' Mazzaella japonica'' have a negative impact on the growth of ''C. exasperatus''. ''C. exasperatus'' is also susceptible to infection by the

parasitic Parasitism is a close relationship between species, where one organism, the parasite, lives on or inside another organism, the host, causing it some harm, and is adapted structurally to this way of life. The entomologist E. O. Wilson has c ...

oomycete Oomycota forms a distinct phylogenetic lineage of fungus-like eukaryotic microorganisms, called oomycetes (). They are filamentous and heterotrophic, and can reproduce both sexually and asexually. Sexual reproduction of an oospore is the resul ...

'' Pythium marinum''. ''C. exasperatus'' decomposes quickly, faster than most other species, indicating its importance to

detritivore Detritivores (also known as detrivores, detritophages, detritus feeders, or detritus eaters) are heterotrophs that obtain nutrients by consuming detritus (decomposing plant and animal parts as well as feces). There are many kinds of invertebrates, ...

s and to nutrient cycling. The high rate of decomposition also means that it is harder to find washed ashore as wrack and that its importance in the ecosystem may be underrepresented in research. However,

amphipods Amphipoda is an order of malacostracan crustaceans with no carapace and generally with laterally compressed bodies. Amphipods range in size from and are mostly detritivores or scavengers. There are more than 9,900 amphipod species so far descri ...

such as ''

Megalorchestia californiana ''Megalorchestia californiana'' is a species of sand-hopper in the family Talitridae. It was first described in 1851 by the German naturalist Johann Friedrich von Brandt and is the type species of the genus '' Megalorchestia''. It is commonly ...

'' and '' Traskorchestia spp.'' (including '' Traskorchestia traskiana'') will avoid ''C. exasperatus''. The

isopod Isopoda is an order of crustaceans that includes woodlice and their relatives. Isopods live in the sea, in fresh water, or on land. All have rigid, segmented exoskeletons, two pairs of antennae, seven pairs of jointed limbs on the thorax, an ...

'' Ligia pallasii'' and the green sea urchin (''

Strongylocentrotus droebachiensis ''Strongylocentrotus droebachiensis'' is commonly known as the green sea urchin because of its characteristic green color. It is commonly found in northern waters all around the world including both the Pacific and Atlantic Oceans to a northerly ...

'') also seems to prefer to eat other seaweed species. A diet of ''C. exasperatus'' can slow or decrease shell length in juvenile white abalone ('' Haliotis sorenseni'') at extreme water temperatures, and possibly can be deadly at 18 °C or above raising concerns related to

global warming In common usage, climate change describes global warming—the ongoing increase in global average temperature—and its effects on Earth's climate system. Climate change in a broader sense also includes previous long-term changes to E ...

Use by humans

Commercial

aquaculture Aquaculture (less commonly spelled aquiculture), also known as aquafarming, is the controlled cultivation ("farming") of aquatic organisms such as fish, crustaceans, mollusks, algae and other organisms of value such as aquatic plants (e.g. lot ...

in both tanks and on nets of ''C. exasperatus'' was attempted as early as the 1970s in

Washington state Washington (), officially the State of Washington, is a state in the Pacific Northwest region of the Western United States. Named for George Washington—the first U.S. president—the state was formed from the western part of the Washington ...

. It can also be grown in the air if sprayed with sea water, which conserves water but risks losing the crop if the pumps fail. The gel within the blades has also been harvested to make

cosmetics Cosmetics are constituted mixtures of chemical compounds derived from either natural sources, or synthetically created ones. Cosmetics have various purposes. Those designed for personal care and skin care can be used to cleanse or protect ...

. Intact blades are used in baths or for

thalassotherapy Thalassotherapy (from the Greek word ''thalassa'', meaning "sea") is the use of seawater as a form of therapy. Note: Thalasso therapy is a sub-definition under the listing for Thalasso. It also includes the systematic use of sea products and shore ...

, along with species such as feather boa (''

Egregia menziesii ''Egregia menziesii'' is a species of kelp known commonly as feather boa kelp. It is the only species in the monotypic genus ''Egregia''. It is native to the coastline of western North America from Alaska to Baja California, where it is a com ...

''), finger kelp (''

Laminaria digitata ''Laminaria digitata'' is a large brown alga in the family Laminariaceae, also known by the common name oarweed. It is found in the sublittoral zone of the northern Atlantic Ocean. Description ''Laminaria digitata'' is a tough, leathery, dark ...

''), and ''

Fucus ''Fucus'' is a genus of brown algae found in the intertidal zones of rocky seashores almost throughout the world. Description and life cycle The thallus is perennial with an irregular or disc-shaped holdfast or with haptera. The erect portion o ...

''.

Gallery

References

{{Authority control Gigartinaceae Species described in 1851