Chondracanthus exasperatus

It is a perennial species. It can be confused with Chondracanthus spinosus and Gigartina binghamiae, and it might take RFLP analysis to be sure of the species. The color of the thallus is greenish when exposed to ultraviolet light, but when it grows in deeper water it is darker red to purple. As originally described, C. exasperatus has a leafy stipe, with large long leathery-membranaceous blades that are lanceolate and simple. The blade, and the majority of the thallus, is purplish-red. Blade margins are thick, with rounded teeth, and appendiculate. Thalli have a moisture content of about 81.4% and protein content of 1.59-1.97%. ==Distribution and habitat==

C. exasperatus is found on the Pacific coast of North America from Baja California north to Sitka Sound. The type locality is in Puget Sound opposite Fort Nisqually. ==Ecology==

Proliferation of invasive species such as Mazzaella japonica have a negative impact on the growth of C. exasperatus. C. exasperatus is also susceptible to infection by the parasitic oomycete Pythium marinum. C. exasperatus decomposes quickly, faster than most other species, indicating its importance to detritivores and to nutrient cycling.) will avoid C. exasperatus. The isopod Ligia pallasii and the green sea urchin (Strongylocentrotus droebachiensis) 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. ==Use by humans==

Commercial aquaculture in both tanks and on nets of C. exasperatus was attempted as early as the 1970s in Washington state. 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. Intact blades are used in baths or for thalassotherapy, along with species such as feather boa (Egregia menziesii), finger kelp (Laminaria digitata), and Fucus. ==Gallery==