''Ceratophyllus gallinae'', known as the hen flea in Europe or the European chicken flea elsewhere, is an

ectoparasite Parasitism is a Symbiosis, close relationship between species, where one organism, the parasite, lives (at least some of the time) on or inside another organism, the Host (biology), host, causing it some harm, and is Adaptation, adapted str ...

of birds. This

flea Flea, the common name for the order (biology), order Siphonaptera, includes 2,500 species of small flightless insects that live as external parasites of mammals and birds. Fleas live by hematophagy, ingesting the blood of their hosts. Adult f ...

was first described by the German botanist and entomologist

Franz von Paula Schrank Franz von Paula Schrank (21 August 1747, in Neuhaus am Inn, Vornbach – 22 December 1835) was a German priest, botanist and entomologist. Biography He was ordained as a priest in Vienna in 1784, gaining his doctorate in theology two years lat ...

in 1803.

Taxonomy

''Ceratophyllus gallinae'' was first described as ''Pulex gallinae'' by

in 1803 in the third volume of his ''Fauna Boica''. It was eventually moved to the genus '' Ceratophyllus'', which was described in 1832 by John Curtis, in his '' British Entomology''. In this genus, ''C. gallinae'' is a member of the nominate subgenus, ''Ceratophyllus''.

Distribution

''C. gallinae'' originated in Europe but became cosmopolitan with the spread of poultry. It is more prevalent in cooler regions. These fleas are estimated to occupy a range of .

Description

The adult ''Ceratophyllus gallinae'' is some long, laterally flattened, and brown. It has a pair of simple eyes, a proboscis for sucking blood, and a characteristic four to six bristles on the femur of the hind leg. The basal segments of the legs do not bear spines. Adults lack a genal ctenidium but have a noticeable pronotal ctenidium.

Hosts

''Ceratophyllus gallinae'' has a broad host range, being associated with several species of birds with dry cavity or semi-cavity nests, mostly constructed in bushes and trees. It commonly attacks

poultry Poultry () are domesticated birds kept by humans for the purpose of harvesting animal products such as meat, Eggs as food, eggs or feathers. The practice of animal husbandry, raising poultry is known as poultry farming. These birds are most typ ...

, and can bite humans and other

mammal A mammal () is a vertebrate animal of the Class (biology), class Mammalia (). Mammals are characterised by the presence of milk-producing mammary glands for feeding their young, a broad neocortex region of the brain, fur or hair, and three ...

s. Another bird flea, '' C. garei'', is associated with the often wet, ground-built nests of ducks, waders and other water birds. A third common bird flea, found on many hosts, is the moorhen flea, and this, in contrast to the other two species, hitches a ride on the bird itself rather than living almost exclusively in its nest, and thus becomes widely dispersed. A further species with multiple bird hosts is '' C. borealis'', found in the nests of

passerine A passerine () is any bird of the order Passeriformes (; from Latin 'sparrow' and '-shaped') which includes more than half of all bird species. Sometimes known as perching birds, passerines generally have an anisodactyl arrangement of their ...

s and cliff-nesting sea birds. ''C. borealis'' has been known to hybridise with ''C. gallinae''. ''Ceratophyllus gallinae'' is most prevalent in birds with nests in nest-holes and crevices. Infestations of nests in nest-holes and crevices are also more intense, meaning that there are more wintering ''C. gallinae'' in those nests. There are reasons to believe that the original host of ''C. gallinae'' was a tit, but the flea is now present, via domestic poultry, on numerous islands where there are no representatives of the tit family. The tit family does provide the optimal reproductive conditions for ''C. gallinae'', suggesting that it is the main host of this species. This flea has often been recorded from

squirrel Squirrels are members of the family Sciuridae (), a family that includes small or medium-sized rodents. The squirrel family includes tree squirrels, ground squirrels (including chipmunks and prairie dogs, among others), and flying squirrel ...

s' dreys, and squirrel fleas have been found in birds' nests. When a domestic cat catches a bird, it often plays with it, and as the bird cools, any fleas it carries are likely to transfer to the warm-blooded cat. There they can feed, but whether they can survive for some time and breed on the cat is unclear.

Ecology

Although many species of flea require a blood meal before they can copulate, that is not the case with ''Ceratophyllus gallinae''. As with other fleas, the life cycle consists of eggs, the larval stages, a pupal stage and an adult stage. The larvae have chewing jaws and it is only the adult fleas that are capable of biting the host. Under optimal conditions of temperature and humidity, adults can emerge from the cocoon in 23 days. How many generations there are in the year depends on how many broods their host bird rears. The fleas usually undergo

metamorphosis Metamorphosis is a biological process by which an animal physically develops including birth transformation or hatching, involving a conspicuous and relatively abrupt change in the animal's body structure through cell growth and different ...

and overwinter as pre-emergent adults. These are fully formed within the cocoon and emerge when certain stimuli occur; suitable stimuli are vibration, heat, or increased levels of

carbon dioxide Carbon dioxide is a chemical compound with the chemical formula . It is made up of molecules that each have one carbon atom covalent bond, covalently double bonded to two oxygen atoms. It is found in a gas state at room temperature and at norma ...

. These fleas generally come into contact with their host by jumping. The jumping is found to be initiated when the intensity of light is reduced. The host is infected during the spring, when it is foraging on the ground. Fleas like ''C. gallinae'' that are found in nests often develop a defined breeding season, which coincides with that of their host. Associated with this is their ability to survive away from the host. ''C. gallinae'' has often been collected far away from its host or the host's nest, under flakes of bark, in cracks or among leaves, where it fasts for an indeterminate period. The largest number of ''C. gallinae'' reported from a single bird's nest was 5,754 fleas, from the nest of a coal tit.

References

{{Taxonbar, from=Q5063801 Ceratophyllidae Ectoparasites Parasites of birds Insects described in 1803 Insects of Europe