''Skrjabingylus nasicola'' is a species of parasitic

nematode The nematodes ( or ; ; ), roundworms or eelworms constitute the phylum Nematoda. Species in the phylum inhabit a broad range of environments. Most species are free-living, feeding on microorganisms, but many are parasitic. Parasitic worms (h ...

in the family Metastrongylidae. Its lifecycle includes an intermediary mollusc host and a paratenic host, a shrew or small rodent. The adult worms live in the nasal sinuses of

mustelid The Mustelidae (; from Latin , weasel) are a diverse family of carnivoran mammals, including weasels, badgers, otters, polecats, martens, grisons, and wolverines. Otherwise known as mustelids (), they form the largest family in the suborde ...

s that have eaten the paratenic hosts.

Infection

Hansson (1977) showed that direct transmission of the nematode from mustelid to mustelid did not occur, nor did infection occur when the mustelid was fed on small

rodent Rodents (from Latin , 'to gnaw') are mammals of the Order (biology), order Rodentia ( ), which are characterized by a single pair of continuously growing incisors in each of the upper and Mandible, lower jaws. About 40% of all mammal specie ...

amphibian Amphibians are ectothermic, anamniote, anamniotic, tetrapod, four-limbed vertebrate animals that constitute the class (biology), class Amphibia. In its broadest sense, it is a paraphyletic group encompassing all Tetrapod, tetrapods, but excl ...

s, molluscs, arthropods, or

earthworms An earthworm is a soil-dwelling terrestrial animal, terrestrial invertebrate that belongs to the phylum Annelida. The term is the common name for the largest members of the class (biology), class (or subclass (biology), subclass, depending on ...

. Infection could occur when the animal was fed on the common shrew (''Sorex aranea''); larvae of the nematode began to be excreted by the mustelid some three weeks later. Research since then has shown that rodents can be a source of infection for mustelids.

Lifecycle

''Skrjabingylus nasicola'' has a complex lifecycle. Larvae passed in the

faeces Feces (also known as faeces American and British English spelling differences#ae and oe, or fæces; : faex) are the solid or semi-solid remains of food that was not digested in the small intestine, and has been broken down by bacteria in the ...

of infected mustelids are ingested by slugs such as '' Deroceras reticulatum''. Mustelids do not usually eat molluscs, but the slugs may be eaten by a mammalian paratenic host such as ''

Apodemus ''Apodemus'' is a genus of Muridae, murid (true mice and rats) containing the field mice as well as other well-known species like the wood mouse and the yellow-necked mouse. The name is unrelated to that of the ''Mus (genus), Mus'' genus, instead ...

'' sp. or '' Clethrionomys glareolus''. No developmental stages take place in this host and the nematode rests in the glandular zones in the head or possibly in the muscle or connective tissue. Further development takes place when this host is eaten by a mustelid and the parasite moves into its nasal tissues.

References

{{Taxonbar, from=Q5268946 Strongylida Parasitic nematodes of mammals Nematodes described in 1842