Springtail

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{{Taxobox | color = pink | name = Springtails | image = Onychiurus-on-Birch.JPG | image_width = 300px | image_caption = Orchesella on a birch | regnum = Animalia | phylum = Arthropoda | subphylum = Hexapoda | classis = Entognatha | ordo = Collembola | ordo_authority = Lubbock, 1870 | subdivision_ranks = Families | subdivision = Suborder Arthropleona
  Superfamily Entomobryoidea
   Entomobryidae - slender springtails
   Isotomidae - smooth springtails
   Oncopoduridae
   Paronellidae
   Tomoceridae
  Superfamily Poduroidea
   Brachystomellidae
   Hypogastruridae - elongate-bodied springtails
   Neanuridae
   Odontellidae
   Onychiuridae - blind springtails
   Poduridae - water springtails
Suborder Symphypleona
   Dicyrtomidae
   Katiannidae
   Sminthuridae - globular springtails
   Sminthurididae
   Bourletiellidae
   Arrhopalitidae
}}

Springtails (Order Collembola) form the largest of the three orders of modern Hexapods that are no longer considered to be insects (along with the Protura and Diplura). The three orders are sometimes grouped together in a class called Entognatha because they have internal mouth parts, but they do not appear to be more closely related to one another than they are to the insects, which have external mouthparts. Recent genetic studies suggest that the Collembola are a separate evolutionary line from the other Hexapoda.

Members of Collembola are normally less than 6 mm in length, have six or fewer abdominal segments and possess a tubular appendage (the collophore) in the first abdominal segment. An abdominal, tail-like appendage, called the furcula, is present in most species and is folded beneath the body, to be used for jumping when the animal is threatened. Springtails are frequently found in leaf litter and other decaying material. The suborder Arthropleona has an elongated body in contrast to the globular body of the Symphypleona.

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