(Neotrombicula autumnalis)
Biology:
Autumn mites are very small, up to 0.3 mm in size, orange-red colored animals that have 6 legs as larvae and 8 legs in the adult stage. They belong to the arachnid family.
The development of the fall mite proceeds via egg, larva and various nymph stages to the adult animal.
In warm, humid and sunny weather, the larvae that hatch from the eggs laid on the ground climb up through the low vegetation and wait for a potential host at a height of 5 to 20 cm.
Their hosts are mostly birds and small rodents, but also dogs, cats or humans, from which they are stripped off in the grass, for example.
Like ticks, for example, they seek out warm, moist areas with thin skin on the host’s skin. They scratch the skin with their mouthparts and secrete a saliva secretion that dissolves tissue. They usually feed on cell sap and lymph, only rarely do they damage a blood vessel and then ingest blood. After sucking, they drop off and develop through three nymph stages into adults, which do not live parasitically and inhabit the soil. Humans are actually a false host for the animals. They therefore only suck on them for a relatively short time and soon let go again after being ingested outdoors and carried into the home. This is why they can be found in floor dust.
Damage:
Autumn or harvest mites occur in large numbers outdoors, especially on warm late summer days. Only their larvae suck on humans and animals, the imagines do not live parasitically!
Their sucking activity causes unpleasant itchy rashes (harvest scabies, also known as “autumn bite” or trombidiosis). The itching can be almost unbearable, especially in the warmth of the bed.
