The moorhen flea, Dasypsyllus gallinulae, originally from South America, is now a globally widespread flea

Flea

Flea is the common name for insects of the order Siphonaptera which are wingless insects with mouthparts adapted for piercing skin and sucking blood...

 species. It is a large flea, easily identified because the male has two heavy horn-like spines on one of the genital flaps, and the female has a deep "bite" on the seventh sternite

Sternum (arthropod)

The sternum is the ventral portion of a segment of an arthropod thorax or abdomen.In insects, the sterna are usually single, large sclerites, and external...

.

It is found in bird nests, and is more likely to be found on the bird's body than, say, the chicken flea Dasypsyllus gallinae, which is normally found in the nest. The moorhen flea's many hosts include the Common Moorhen

Common Moorhen

The Common Moorhen is a bird in the Rallidae family with an almost worldwide distribution. The North and South American Committees of the AOU and the IOC have voted on or before July 2011 to split the American forms into a new species Common Gallinule, however, no other committee has voted to...

, Eurasian Woodcock

Eurasian Woodcock

The Eurasian Woodcock, Scolopax rusticola, is a medium-small wading bird found in temperate and subarctic Eurasia. It has cryptic camouflage to suit its woodland habitat, with reddish-brown upperparts and buff-coloured underparts...

, grouse

Grouse

Grouse are a group of birds from the order Galliformes. They are sometimes considered a family Tetraonidae, though the American Ornithologists' Union and many others include grouse as a subfamily Tetraoninae in the family Phasianidae...

, European Robin

European Robin

The European Robin , most commonly known in Anglophone Europe simply as the Robin, is a small insectivorous passerine bird that was formerly classed as a member of the thrush family , but is now considered to be an Old World flycatcher...

, Goldcrest

Goldcrest

The Goldcrest, Regulus regulus, is a very small passerine bird in the kinglet family. Its colourful golden crest feathers gives rise to its English and scientific names, and possibly to it being called the "king of the birds" in European folklore. Several subspecies are recognised across the very...

, Willow Tit

Willow Tit

The Willow Tit is a passerine bird in the tit family Paridae. It is a widespread and common resident breeder throughout temperate and subarctic Europe and northern Asia. It is more of a conifer specialist than the closely related Marsh Tit, which explains it breeding much further north...

 and Eurasian Treecreeper.