''Spilopsyllus cuniculi'', the rabbit flea, is a species of

flea Flea, the common name for the order Siphonaptera, includes 2,500 species of small flightless insects that live as external parasites of mammals and birds. Fleas live by ingesting the blood of their hosts. Adult fleas grow to about long, 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 ...

Pulicidae The Pulicidae are a flea family in the order Siphonaptera. Currently, this family has 181 species in 27 genera. Of these, 16 are known from North America. Like all 2,500 Siphonaptera, the Pulicidae are ectoparasites. These fleas are wingless, ...

. It is an external

parasite 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 rabbits and hares and is occasionally found on cats and dogs and also certain seabirds that nest in burrows. It can act as a

vector Vector most often refers to: *Euclidean vector, a quantity with a magnitude and a direction *Vector (epidemiology), an agent that carries and transmits an infectious pathogen into another living organism Vector may also refer to: Mathematic ...

for the

virus A virus is a submicroscopic infectious agent that replicates only inside the living cells of an organism. Viruses infect all life forms, from animals and plants to microorganisms, including bacteria and archaea. Since Dmitri Ivanovsk ...

that causes the rabbit disease

myxomatosis Myxomatosis is a disease caused by ''Myxoma virus'', a poxvirus in the genus '' Leporipoxvirus''. The natural hosts are tapeti (''Sylvilagus brasiliensis'') in South and Central America, and brush rabbits (''Sylvilagus bachmani'') in North A ...

Description

The rabbit flea is about long and a dark brown colour. It is laterally compressed, has three pairs of legs and no wings. Its head is held at an angle to its body and its mouthparts are adapted for piercing the skin of its host and sucking its blood. It has a pronotal comb or row of spines just behind the head and a genal comb of spines below the head and these help to distinguish it from other species of flea.

Host species

The rabbit flea is found worldwide, usually as an external parasite found on rabbits and hares but occasionally also on cats and dogs. It can work its way through the animal's fur but is usually found in clusters around the bases of the host's ears. On some of the islands off the coasts of the United Kingdom it can be found on Manx shearwaters and Atlantic puffins, presumably because the birds nest in burrows and often take over holes previously occupied by rabbits.

Life cycle

Adult female rabbit fleas can detect the changing levels of certain

hormone A hormone (from the Greek participle , "setting in motion") is a class of signaling molecules in multicellular organisms that are sent to distant organs by complex biological processes to regulate physiology and behavior. Hormones are require ...

s in a female rabbit's blood that show that she is near to

parturition Birth is the act or process of bearing or bringing forth offspring, also referred to in technical contexts as parturition. In mammals, the process is initiated by hormones which cause the muscular walls of the uterus to contract, expelling the f ...

. This triggers sexual maturity in the fleas and they mate and start producing eggs. As soon as the young rabbits are born, the fleas move onto them and start feeding, mating and laying eggs. About twelve days later, they return to the mother rabbit. They complete this migration every time she produces a litter of young. Piper, Ross (2007), ''Extraordinary Animals: An Encyclopedia of Curious and Unusual Animals'', Greenwood Press. The larvae are legless grubs, creamy-white with a brown head. After three larval stages they pupate. Fleas newly emerged from the pupa need to have a blood meal within a week, otherwise they will die. After that they can survive for many months without feeding. The optimum temperature for the flea's life cycle is 70 °F to 85 °F (21 °C to 30 °C).

Disease transmission

Myxomatosis is a virus disease of rabbits which can be fatal. The symptoms are swelling of the eyelids and lips, conjunctivitis and the formation of skin tumours on the face, ears and limbs. The rabbit flea acts as a vector for the disease and the virus has been shown to remain viable in the flea's mouthparts for at least one hundred days. The rabbit flea has also been implicated in the transmission of the '' Bartonella alsatica''

bacterium Bacteria (; singular: bacterium) are ubiquitous, mostly free-living organisms often consisting of one biological cell. They constitute a large domain of prokaryotic microorganisms. Typically a few micrometres in length, bacteria were amon ...

, an opportunistic

pathogen In biology, a pathogen ( el, πάθος, "suffering", "passion" and , "producer of") in the oldest and broadest sense, is any organism or agent that can produce disease. A pathogen may also be referred to as an infectious agent, or simply a germ ...

that causes disease in animals and man.

References

{{Taxonbar, from=Q10675774 Pulicidae Parasitic arthropods of mammals