Like these freeloading mites!
Yes, a newly-discovered mite showed a peculiar way of living: living on spider webs and stealing food. This is actually a first!
In Brazil’s Lapa Nova cave, Leopoldo Ferreira de Oliveira Bernardi at the Federal University of Lavras in Minas Gerais first found live mites dotting a spider web. This relationship sparked his curiosity. Moreover, after finding the same thing in differen cave, he did little experiment. He placed a live cave moth (bait) on a mites-infested spider web. Of course, the arachnid had to attack the moth as soon as possible then eat it.
However, he couldn't believe his eyes after: in the next 5 to 40 minutes, the scattered mites gathered in one whole group to eat the moth. These mites have been recently named as Callidosoma cassiculophylla: “cassiculus” means “spider web” and “phylla” means “friend”.
“Spiders and their webs are predictable sources of food, and many animals regularly exploit this resource,” says zoologist Lidianne Salvatierra at the National Institute of Amazonian Research in Manaus, Brazil. “These ‘thieves’ are specialised spiders, scorpion flies, flies, plant bugs, gnats and also hummingbirds.” But, again, this is the first one wherein mites are observed to do the same.
“The fact that the mites involved in the relationship are adult is interesting,” says Robert Pape at the University of Arizona Insect Collection. “In this regard, Callidosoma cassiculophylla is unusual.”
And these mites aren't playing; they won't eat scraps! That is, they'll only devour spider’s freshly-killed prey and not scavenge. Ready for another surprise?
The spider seemed so unbothered at all! No, not annoyed at all with these freeloaders! No signs of aggression were actually observed. “I saw a mite walk under the spider’s legs and nothing happened,” says Bernardi.
“The mites are too small to be useful prey for the spiders, and are not large enough to be a potential predator,” says Pape. “I suspect the spiders are not adversely affected by the small amount of nutrients consumed by the mites.”
Spiders and mites, not a very good combination, is it?
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