Hyppyhäntäiset

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.

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.

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).

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).

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