The leather star (''Dermasterias imbricata'') is a

sea star Starfish or sea stars are star-shaped echinoderms belonging to the class Asteroidea (). Common usage frequently finds these names being also applied to ophiuroids, which are correctly referred to as brittle stars or basket stars. Starfish a ...

in the

family Family (from la, familia) is a group of people related either by consanguinity (by recognized birth) or affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its members and of society. Idea ...

Asteropseidae Asteropseidae is a family of sea stars Starfish or sea stars are star-shaped echinoderms belonging to the class Asteroidea (). Common usage frequently finds these names being also applied to ophiuroids, which are correctly referred to as ...

found at depths to off the western seaboard of North America. It was first described to science by

Adolph Eduard Grube Adolph Eduard Grube (18 May 1812, Königsberg – 23 June 1880 , Breslau) was a German zoologist. Adolph Eduard Grube, an able worker in many animal groups, was mainly interested in Polychaetes. In 1837 he defended his thesis at the University of ...

in 1857.

Description

The leather star has a broad central disc and five plump, short arms which taper broadly from the central disc. The arms have two rows of tube feet and no bordering marginal plates. The upper, aboral, surface is smooth and velvety, made more so by the absence of spines and a light layer of mucous. It is covered with a reticulated pattern in reddish-brown, often with patches of greyish-blue. No

pedicellaria A pedicellaria (plural: pedicellariae) is a small wrench- or claw-shaped appendage with movable jaws, called valves, commonly found on echinoderms (phylum Echinodermata), particularly in sea stars (class Asteroidea) and sea urchins (class Echi ...

e are present, but the

madreporite The madreporite is a light colored calcareous opening used to filter water into the water vascular system of echinoderms. It acts like a pressure-equalizing valve. It is visible as a small red or yellow button-like structure, looking like a sma ...

can be seen. This starfish can grow to about in diameter and has a distinctive smell that resembles garlic and sulphur.Marine Biodiversity of British Columbia
Zipcode Zoo

Distribution and habitat

The range of the leather star includes the western seaboard of North America from

Cook Inlet Cook Inlet ( tfn, Tikahtnu; Sugpiaq: ''Cungaaciq'') stretches from the Gulf of Alaska to Anchorage in south-central Alaska. Cook Inlet branches into the Knik Arm and Turnagain Arm at its northern end, almost surrounding Anchorage. On its so ...

Alaska Alaska ( ; russian: Аляска, Alyaska; ale, Alax̂sxax̂; ; ems, Alas'kaaq; Yup'ik: ''Alaskaq''; tli, Anáaski) is a state located in the Western United States on the northwest extremity of North America. A semi-exclave of the U.S. ...

to northern Mexico. It occurs 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 ...

. It lives in the intertidal zone and in deeper water down to depths of about . It is found on rocky bottoms and occasionally sandy seabeds.

Biology

Dermasterias imbricata (4628744017) (cropped)

The leather star feeds on algae and a range of invertebrates, including other asteroids,

bryozoa Bryozoa (also known as the Polyzoa, Ectoprocta or commonly as moss animals) are a phylum of simple, aquatic invertebrate animals, nearly all living in sedentary colonies. Typically about long, they have a special feeding structure called a ...

ns, sea urchins,

sponge Sponges, the members of the phylum Porifera (; meaning 'pore bearer'), are a basal animal clade as a sister of the diploblasts. They are multicellular organisms that have bodies full of pores and channels allowing water to circulate throug ...

s, sea cucumbers,

hydroids Hydroids are a life stage for most animals of the class Hydrozoa, small predators related to jellyfish. Some hydroids such as the freshwater '' Hydra'' are solitary, with the polyp attached directly to the substrate. When these produce buds ...

sea pen Sea pens are colonial marine cnidarians belonging to the order Pennatulacea. There are 14 families within the order; 35 extant genera, and it is estimated that of 450 described species, around 200 are valid. Sea pens have a co ...

s, and colonial

tunicate A tunicate is a marine invertebrate animal, a member of the subphylum Tunicata (). It is part of the Chordata, a phylum which includes all animals with dorsal nerve cords and notochords (including vertebrates). The subphylum was at one time ...

s. It is in turn preyed on by the morning sun star (''Solaster dawsoni''). In its attempts to evade this voracious

predator Predation is a biological interaction where one organism, the predator, kills and eats another organism, its prey. It is one of a family of common feeding behaviours that includes parasitism and micropredation (which usually do not kill th ...

, it crawls away at a maximum speed of 15 cm/min, but this is too slow, and leather stars make up 50% of the diet of morning sun stars. Off the Washington coast, spawning is from April to August. The females release yellow eggs which are fertilized in the

water column A water column is a conceptual column of water from the surface of a sea, river or lake to the bottom sediment.Munson, B.H., Axler, R., Hagley C., Host G., Merrick G., Richards C. (2004).Glossary. ''Water on the Web''. University of Minnesota-D ...

. The larvae then become part of the

zooplankton Zooplankton are the animal component of the planktonic community ("zoo" comes from the Greek word for ''animal''). Plankton are aquatic organisms that are unable to swim effectively against currents, and consequently drift or are carried along by ...

. The leather star sometimes lives

symbiotically Symbiosis (from Greek , , "living together", from , , "together", and , bíōsis, "living") is any type of a close and long-term biological interaction between two different biological organisms, be it mutualistic, commensalistic, or parasit ...

with the scaleworm '' Arctonoe vittata''. The worm also associates with various other marine invertebrates, but if separated from its host, will search out another member of the same species. The worm may nip off the heads of small tube-dwelling polychaetes as the starfish moves around, but is not harmed by its host.''Arctonoe vittata''
The parasitic barnacle genus ''

Dendrogaster ''Dendrogaster'' is a genus of crustaceans belonging to the family Dendrogastridae Dendrogastridae is a family of crustaceans belonging to the order Dendrogastrida Dendrogastrida is an order of crustaceans belonging to the class Maxillopoda ...

'' is sometimes an

endoparasite 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 ...

of the leather star.

References

{{Taxonbar, from=Q2618140 leather star Western North American coastal fauna leather star leather star