dcsimg

Brief Summary

    Springtail: Brief Summary
    provided by wikipedia

    Springtails (Collembola) form the largest of the three lineages of modern hexapods that are no longer considered insects (the other two are the Protura and Diplura). Although the three orders are sometimes grouped together in a class called Entognatha because they have internal mouthparts, they do not appear to be any more closely related to one another than they all are to insects, which have external mouthparts.

    Some DNA sequence studies suggest that Collembola represent a separate evolutionary line from the other Hexapoda, but others disagree; this seems to be caused by widely divergent patterns of molecular evolution among the arthropods. The adjustments of traditional taxonomic rank for springtails reflects the occasional incompatibility of traditional groupings with modern cladistics: when they were included with the insects, they were ranked as an order; as part of the Entognatha, they are ranked as a subclass. If they are considered a basal lineage of Hexapoda, they are elevated to full class status.

    Collembolans are omnivorous, free-living organisms that prefer moist conditions. They do not directly engage in the decomposition of organic matter, but contribute to it indirectly through the fragmentation of organic matter and the control of soil microbial communities. The word "Collembola" is from the ancient Greek κόλλα kólla "glue" and ἔμβολος émbolos "peg"; this name was given due to the existence of the collophore, which was previously thought to stick to surfaces in order to stabilize the creature.

    Brief Summary
    provided by EOL authors

    Worldwide ca. 6500 collembolan species are listed, belonging to 18 families (Hopkin 1997). For Europe, there are estimated to be ca. 1500 species, belonging to 16 families (taxonomic work is still progressing).

    Collembola are the most abundant terrestrial arthropods, colonising all soil habitats that provide enough humidity and food, such as organic matter or microorganisms. Example habitats include root rosettes of high alpine plants, plant debris on the shore, natural soils, as well as microhabitats such as flower pots. Most species are soil or litter dwellers, whilst only few species live on the surface or in the vegetation (mainly Entomobryidae and Symphypleona). In mature soil, abundances may attain values of 50–100,000 individuals/m2. Local gradations in abundance are a well known phenomenon in many Collembola.

Comprehensive Description

Trophic Strategy

    Trophic Strategy
    provided by EOL authors
    The Collembola fauna function lead us to formation of soil (nutrient cicling) and to feeding habit on litter, clay, fungi, bacteria, and other taxa, even the same taxa, sometimes cited as pantophagous because of this.

    The diversity of fungi found in the natural soil was 33 times higher than that in the guts of the collembolan Protaphorura armata (Jørgensen et al., 2005).

    Collembolans can preferentially select certain taxa of fungi when feeding in soils, and on the other hand, studies have also indicated that collembolans have an opportunistic feeding behaviour; available resources in the immediate proximity of the animals rather than the specific distributed resources are ingested (Ponge, 2000).

    At a lower depth (2–4 cm) springtails ate mainly fungal material, hemorganic and holorganic humus. Gut contents of the species living at the lowest depth were mostly composed of mycorrhizae and higher plant material. In particular, holorganic humus and fungal material dominated the food bolus in bulked Collembola, even in animals found in the first top 2 cm (Ponge, 2000).

    Some studies have shown that Collembola prefer saprophytic and pathogenic to mycorrhizal fungi and, among saprophytic fungi, actively metabolizing to senescent mycelia. Feeding of Collembola on active mycorrhiza would be expected to decrease plant growth by inhibiting nutrient uptake. However, if Collembola feed primarily on low vitality and dead mycelia that have already been severed from the plant, this could have a positive effect on plant growth, because of enhanced nutrient release from senescent and dead mycelia (Kaneda and Kaneko, 2004).

Population Biology

    Population Biology
    provided by EOL authors
    Springtails have been found in everywhere on earth were there is soil and are active under most environmental conditions – unlike nematodes, bacteria or earthworms (Filser, 2002).

    A very abundant group of soil hexapods, both in terms of species and numbers. Densities range from about 100 to 670,000 individuals/m2 as many as 60 different species may coexist within a few hectares (Petersen and Luxton, 1982).

Risks

    Risks
    provided by EOL authors

    As detritivores, Collembola are not generally considered as pest species. Exceptions are two species of Symphypleona living above ground in the vegetation layer: the European Sminthurus viridis which became a severe pest in Australia on alfalfa, clover etc, and the ubiquitous Bourletiella hortensis is known to feed on vegetable seedlings when natural food (weed seedlings) is absent. The ubiquitous onychiurid Protaphorura armata also switches food source in the absence of weeds, but only as a secondary pest when feeding on wounds infected by microorganisms.

Education Resources

    One Species at a Time Podcast: Springtails
    provided by EOL authors

    Springtails are tiny creatures that live underfoot in the soil and leaf litter. Most people are not even aware they exist. Until 2000, biologists classified these curious animals as insects. Then new DNA evidence forced scientists like Louis Deharveng to revise their thinking and redraw a branch on the tree of life.

    Listen to this podcast