''Pyura haustor'' is a
species of
sessile ascidian, or sea squirt, that lives in coastal waters in the north-eastern Pacific Ocean, attached to rocks or artificial structures. Common names for this species include the wrinkled seapump, the wrinkled sea squirt and the warty tunicate.
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]
Description
This sea squirt is nearly as tall as it is wide, growing to about . It is not attached to the substrate
Substrate may refer to:
Physical layers
*Substrate (biology), the natural environment in which an organism lives, or the surface or medium on which an organism grows or is attached
** Substrate (locomotion), the surface over which an organism lo ...
by a stalk, as are some members of the genus, but is attached over a wide base and appears roughly globular, with two obvious siphons projecting upwards. these siphons can be projected a long way when feeding, and can be retracted if danger threatens. The tunic is tough, wrinkled and folded, and does not have spiny projections. The color is usually dark brown, tinged with red on the siphons, but much of the surface is often hidden by sand, shell fragments or debris adhering to the tunic, or the tunic may be overgrown with other organisms.
Distribution and habitat
''Pyura haustor'' is native to the northeastern Pacific Ocean where its range extends from the Shumagin Islands in Alaska southwards to San Diego County, California
San Diego County (), officially the County of San Diego, is a county in the southwestern corner of the U.S. state of California. As of the 2020 census, the population was 3,298,634, making it California's second-most populous county and the fi ...
. It is found attached to rocks, piers, pilings and floats, as well as to the holdfasts of kelp. It occurs in both sheltered and exposed locations, but in the San Juan Islands, where it is common, it avoids the areas with the strongest currents. Its depth range is from the 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 about .[
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Ecology
Like other tunicates, this sea squirt draws in large quantities of water through its buccal siphon, filters out the edible particles and expels the water through the atrial siphon. Among the planktonic particles ingested are a variety of invertebrate larvae, however researchers have found that the activities of the sea squirt are not sufficient to deplete the local larval populations appreciably.mollusks
Mollusca is the second-largest phylum of invertebrate animals after the Arthropoda, the members of which are known as molluscs or mollusks (). Around 85,000 extant species of molluscs are recognized. The number of fossil species is esti ...
and other tunicates.[
The eggs of this sea squirt are gray, but there are conflicting reports on whether this species liberates the eggs into the water column or whether the developing embryos are brooded. The seastar '']Solaster stimpsoni
''Solaster stimpsoni'', common names Stimpson's sun star, sun star, orange sun star, striped sunstar, and sun sea star, is a species of starfish in the family Solasteridae.
Description
''Solaster stimpsoni'' is a large species, growing up to 5 ...
'' is a predator of this tunicate.[
]
References
{{Taxonbar, from=Q4911485
Stolidobranchia
Animals described in 1864