The echidna flea (''Bradiopsylla echidnae'') is the larger of two 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 ...

commonly found on the

short-beaked echidna The short-beaked echidna (''Tachyglossus aculeatus''), also called the short-nosed echidna, is one of four living species of echidna and the only member of the genus ''Tachyglossus''. It is covered in fur and spines and has a distinctive snou ...

. It is monotypic, that is, the only species in the genus. This flea reaches 4 millimetres in length and has been claimed to be the world's largest flea. This statement is in error as the world's largest flea is known to be the mountain beaver flea which can be as large as 12 millimetres in length. The echidna flea is found on short-beaked Echidnas in southeastern Australia and Tasmania, and although Echidnas are distributed more widely throughout Australasia, it has not been recorded in New Guinea where other species of Echidna occur (

Zaglossus The long-beaked echidnas (genus ''Zaglossus'') make up one of the two extant genus, genera of echidnas, spiny monotremes that live in New Guinea; the other being the short-beaked echidna. There are three living species and one extinct species in ...

and

Tachyglossus The short-beaked echidna (''Tachyglossus aculeatus''), also called the short-nosed echidna, is one of four living species of echidna and the only member of the genus ''Tachyglossus''. It is covered in fur and spines and has a distinctive snout ...

).The echidna flea has also been recorded once on a

Tasmanian devil The Tasmanian devil (''Sarcophilus harrisii'') (palawa kani: purinina) is a carnivorous marsupial of the family Dasyuridae. Until recently, it was only found on the island state of Tasmania, but it has been reintroduced to New South Wales in ...

. The echidna flea has been a subject in several molecular studies as the out-group for

phylogenetic trees A phylogenetic tree (also phylogeny or evolutionary tree Felsenstein J. (2004). ''Inferring Phylogenies'' Sinauer Associates: Sunderland, MA.) is a branching diagram or a tree showing the evolutionary relationships among various biological spec ...

cat The cat (''Felis catus'') is a domestic species of small carnivorous mammal. It is the only domesticated species in the family Felidae and is commonly referred to as the domestic cat or house cat to distinguish it from the wild members of ...

and dog fleas. Evidence suggests that the echidna flea, in large infestation quantities, is responsible for a type of anemia and perhaps even a type of lymphoma in the short-beaked echidna.

References

Fleas Insects of Australia Insects described in 1843 {{Flea-stub