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flea,common name for any of the small, wingless insectsinsect,
invertebrate animal of the class Insecta of the phylum Arthropoda. Like other arthropods, an insect has a hard outer covering, or exoskeleton, a segmented body, and jointed legs. Adult insects typically have wings and are the only flying invertebrates.
..... Click the link for more information. of the order Siphonaptera. The adults of both sexes eat only blood and are all external parasites of mammals and birds. Fleas have hard bodies flattened from side to side and piercing and sucking mouthparts. Their legs are powerful and adapted for fast movement and jumping, enabling them to find new hosts as well as to escape quickly the attempts of the hosts to remove them. The adults can survive away from a host for several weeks without eating. Flea eggs are usually laid in dirt or in the nest of the host; the larvae feed on organic material and the feces of adult fleas. Metamorphosismetamorphosis
[Gr.,=transformation], in zoology, term used to describe a form of development from egg to adult in which there is a series of distinct stages. Many insects, amphibians, mollusks, crustaceans, and fishes undergo metamorphosis, which may involve a change in habitat,
..... Click the link for more information. is complete; the larvae spin silken cocoons when ready to pupate. Many species are not specific to a particular host species, and cat and dog fleas, as well as the human flea of the warmer parts of Europe and Asia, attack humans. Certain rat fleas transmit typhustyphus,
any of a group of infectious diseases caused by microorganisms classified between bacteria and viruses, known as rickettsias. Typhus diseases are characterized by high fever and an early onset of rash and headache.
..... Click the link for more information. and bubonic plagueplague,
any contagious, malignant, epidemic disease, in particular the bubonic plague and the black plague (or Black Death), both forms of the same infection. These acute febrile diseases are caused by Yersinia pestis (Pasteurella pestis
..... Click the link for more information. to humans, and another species transmits tularemiatularemia
or rabbit fever,
acute, infectious disease caused by Francisella tularensis (Pasteurella tularensis). The greatest incidence is among people who handle infected wild rabbits.
..... Click the link for more information. from rabbits. Fleas also transmit several species of tapewormstapeworm,
name for the parasitic flatworms forming the class Cestoda. All tapeworms spend the adult phase of their lives as parasites in the gut of a vertebrate animal (called the primary host).
..... Click the link for more information. that sometimes infest humans. The chigoechigoe
small parasitic flea (Tunga penetrans) of the tropics and subtropics, including the S United States. Humans and their domestic animals are the main hosts.
..... Click the link for more information. is a flea. Water fleas and beach fleas are crustaceanscrustacean
, primarily aquatic arthropod of the subphylum Crustacea. Most of the 44,000 crustacean species are marine, but there are many freshwater forms. The few groups that inhabit terrestrial areas have not been particularly successful in an evolutionary sense; most require
..... Click the link for more information. and not closely related to the insects. Fleas are classified in the phylum ArthropodaArthropoda
[Gr.,=jointed feet], largest and most diverse animal phylum. The arthropods include crustaceans, insects, centipedes, millipedes, spiders, scorpions, and the extinct trilobites.
..... Click the link for more information. , class Insecta, order Siphonaptera.
Any of the wingless insects composing the order Siphonaptera; most are ectoparasites of mammals and birds.
1. any small wingless parasitic blood-sucking insect of the order Siphonaptera, living on the skin of mammals and birds and noted for its power of leaping
2. any of various invertebrates that resemble fleas, such as the water flea and flea beetle