Symphypleona

Definition

An order of springtails (Collembola) characterized by a globular, compact body form in which the thoracic and abdominal segments are fused into a single rounded unit, giving the appearance of a small sphere. Symphypleona are distinguished from the elongate-bodied Entomobryomorpha and Poduromorpha by this fused body plan and by differences in the springing mechanism (furcula) and head capsule structure. They occupy diverse microhabitats including soil litter, vegetation surfaces, and aquatic margins, where they feed primarily on fungi, pollen, and decaying organic matter.

Etymology

From Greek symphyēs 'grown together' + pleōn 'more' or pleura 'side', referring to the fused body segments.

Example

Sminthurus viridis, the lucerne flea, is a widespread agricultural Symphypleonan that forms dense aggregations on legume crops and can reach pest densities in Australian and European pastures.

Synonyms

• globular springtails

Related Terms

• Collembola
• Entomobryomorpha
• Poduromorpha
• Furcula
• springtail
• Entognatha
• hexapod

Usage Notes

Symphypleona is one of three traditionally recognized orders of Collembola, though molecular phylogenetics has sometimes challenged this grouping. The globular body form is an adaptation for rolling into crevices and resisting desiccation, contrasting with the more elongate, flexible bodies of Entomobryomorpha. When springtails were classified as insects, Symphypleona was treated as a suborder; modern taxonomy places Collembola as a separate class within Entognatha or as a subclass of Entognatha, with Symphypleona at order rank. The superfamilies Sminthuridoidea, Katiannoidea, Sturmioidea, Sminthuroidea, and Dicyrtomoidea are currently placed within this order.