''Echinococcus shiquicus'' is a

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 ha ...

worm Worms are many different distantly related bilateral animals that typically have a long cylindrical tube-like body, no limbs, and no eyes (though not always). Worms vary in size from microscopic to over in length for marine polychaete worm ...

first identified in 2005.Xiao N, Qiu J, Nakao M, Li T, Yang W, Chen X, Schantz PM, Craig PS, Ito A. 2005. ''Echinococcus shiquicus'' n. sp., a taeniid cestode from Tibetan fox and plateau pika in China. International Journal for Parasitology, 35, 693–701 It was found in

Tibetan fox The Tibetan fox (''Vulpes ferrilata''), also known as the Tibetan sand fox, is a species of true fox endemic to the high Tibetan Plateau, Ladakh plateau, Nepal, China, Sikkim, and Bhutan, up to elevations of about . It is listed as Least Concern ...

es in the

Qinghai Qinghai (; alternately romanized as Tsinghai, Ch'inghai), also known as Kokonor, is a landlocked province in the northwest of the People's Republic of China. It is the fourth largest province of China by area and has the third smallest po ...

–

Tibet Tibet (; ''Böd''; ) is a region in East Asia, covering much of the Tibetan Plateau and spanning about . It is the traditional homeland of the Tibetan people. Also resident on the plateau are some other ethnic groups such as Monpa people, ...

plateau In geology and physical geography, a plateau (; ; ), also called a high plain or a tableland, is an area of a highland consisting of flat terrain that is raised sharply above the surrounding area on at least one side. Often one or more sides ...

region. Two types of adult worms were recovered and the variant which had a short strobila consisting of single immature and single gravid segments constituted the majority of the specimens. The

strobila Strobilisation or transverse fission is a form of asexual reproduction consisting of the spontaneous transverse segmentation of the body. It is observed in certain cnidarians and helminths. This mode of reproduction is characterized by high offspr ...

, rostellar hooks, location of the

genital pore A sex organ (or reproductive organ) is any part of an animal or plant that is involved in sexual reproduction. The reproductive organs together constitute the reproductive system. In animals, the testis in the male, and the ovary in the female ...

and the number of eggs in gravid uterus helped in differentiating ''Echinococcus shiquicus'' from the other species. The

metacestode A metacestode is the larval stage of a tapeworm, found in an intermediate host In biology and medicine, a host is a larger organism that harbours a smaller organism; whether a parasitic, a mutualistic, or a commensalist ''guest'' (symbiont ...

of ''E. shiquicus'' was detected exclusively from plateau

pika A pika ( or ; archaically spelled pica) is a small, mountain-dwelling mammal found in Asia and North America. With short limbs, very round body, an even coat of fur, and no external tail, they resemble their close relative, the rabbit, but w ...

s. The

larva A larva (; plural larvae ) is a distinct juvenile form many animals undergo before metamorphosis into adults. Animals with indirect development such as insects, amphibians, or cnidarians typically have a larval phase of their life cycle. Th ...

e are unique and they develop into unilocular minicysts approximately 1 cm in diameter within the

liver The liver is a major organ only found in vertebrates which performs many essential biological functions such as detoxification of the organism, and the synthesis of proteins and biochemicals necessary for digestion and growth. In humans, it ...

or lungs.

References

Cestoda Parasites of mammals Animals described in 2005 {{Cestoda-stub