Ant or spider? If you do come across something you think is a spider but looks extremely similar to an ant, this picture isn’t helpful unless you know what to look for. That is because these are ant-mimicking jumping spiders! Think that is super cool? Look up wasp-mimicking jumping spiders.
Ant-mimicking spiders come from the genus “Myrmarachne”, literally meaning ant-spider. Worldwide, this genus has over 180 species—180 different ways to mimic a plethora of ant species. We can slightly alter Zaphod Beeblebrox’s “Count the heads!” to “Count the eyes!” to make sure our quarry is indeed a spider. Red weaver ants have 2 large compound eyes on the side of their head while their mimics, Myrmaplata plataleoides have 4 small eyes at the front of their head. Another marker is that ants, being insects, have 6 legs while the mimics, spiders, have 8. These spiders are such dedicated mimics that they even wave their front legs around like ant antennae. M. plataleoides mimics an Asian red-weaver ant (Oecophylla smaragdina) to perfection, in morphology as well as behaviour.
This incredible mimicry is called Batesian Mimicry, where the spider mimics the ant to ward off predators. Weaver ants taste bad, so predators generally avoid anything that looks somewhat similar to the ant. The spider may even go to the extent of stealing and feeding on larvae from the weavers’ colony to smell like ants. The male of Myrmaplata plataleoides has long ‘chelicerae’(jaw) that enclose long, swordlike fangs. He is probably the greatest swordsman after Jon Snow. He defends his territory and fights other males for the female’s favour. The female doesn’t have elongated jaws and is thus a better mimic.
Salticidae (jumping spiders) isn’t the only spider family to mimic ants. Ants as a taxon are just so successful that many other organisms find it easier to exist as kleptoparasites inside their colonies by donning the scent of ant larva, or to just mimic the ants and feed on them when they draw close.
So the next time you come across a line of red weaver ants, treat yourselves to a smug smile when you identify ‘ants’ that you know are actually spiders!
-Anumit Saralkar (B17)
References: https://inaturalist.ca/taxa/796160-Myrmaplata-plataleoides https://sustain.round.glass/species/when-spiders-mimic-weaver-ants/ https://en.wikipedia.org/wiki/Myrmaplata_plataleoides https://www.antwiki.org/wiki/Ant-Mimicking_Spiders YouTube: The Impostor - Kerengga Ant-Like Jumper | Myrmaplata plataleoides | Ant Mimics Image credits - Sudeep R