''Collinia oregonensis'' is a species of parasitoid

ciliate The ciliates are a group of alveolates characterized by the presence of hair-like organelles called cilia, which are identical in structure to eukaryotic flagella, but are in general shorter and present in much larger numbers, with a differen ...

s of the Colliniidae family. It is known to infect the

krill Krill are small crustaceans of the order Euphausiacea, and are found in all the world's oceans. The name "krill" comes from the Norwegian word ', meaning "small fry of fish", which is also often attributed to species of fish. Krill are consid ...

Euphausia pacifica ''Euphausia pacifica'', the North Pacific krill, is a euphausid that lives in the northern Pacific Ocean. In Japan, ''E. pacifica'' is called ''isada krill'' or ' (ツノナシオキアミ). It is found from Suruga Bay northwards, including all ...

'', ''

Thysanoessa spinifera Thysanoessa Abstract ''Thysanoessa'' is a genus of the krill that play critical roles in the marine food web. They're abundant in Arctic and Antarctic areas, feeding on zooplankton and detritus to obtain energy. Thysanoessa are responsible for ...

'', and ''

Thysanoessa gregaria Thysanoessa Abstract ''Thysanoessa'' is a genus of the krill that play critical roles in the marine food web. They're abundant in Arctic and Antarctic areas, feeding on zooplankton and detritus to obtain energy. Thysanoessa are responsible for ...

'' off the coast of

Oregon Oregon () is a state in the Pacific Northwest region of the Western United States. The Columbia River delineates much of Oregon's northern boundary with Washington, while the Snake River delineates much of its eastern boundary with Idah ...

and

Washington Washington commonly refers to: * Washington (state), United States * Washington, D.C., the capital of the United States ** A metonym for the federal government of the United States ** Washington metropolitan area, the metropolitan area centered o ...

. It caused a mass mortality of ''E. pacifica'' in June 2001 at the base of

Astoria Canyon Astoria Canyon is a submarine canyon 10 miles (16 km) offshore from the mouth of the Columbia River. See also * Astoria Fan The Astoria Fan is a submarine fan. It has sediment, radiating asymmetrically southward from the mouth of th ...

References

* * Protists described in 2006 Oligohymenophorea {{ciliate-stub