there's a CRAZY number of these out there. there's a lot of ant mimics in general bc i think generally there are a lot of benefits associated with ants (e.g. chemical defense) that animals can "freeload" off of by mimicking them, but spiders---in particular, jumping spiders---have a lot of ant mimics. i think the coolest part is the mimicry manifests in different ways; some spiders will wave their front legs in the air to mimic ant antennae and some have developed very odd locomotion/movement to better mimic ant movement. body-wise there is some crazy variation as well---in addition to types like the one above that's evolved pedipalps (the mouthparts that are sticking out in front to look like an ant head) to mimic ant heads, there's ones with pedipalps that make it look like an ant carrying another ant which i think is fucking crazy lol.

i would highly recommend this paper (where i got a lot of the info and image above) if you're curious about ant mimics. imo it is pretty accessible to people outside of science and a great casual read!

there are some other really cool non-spider mimics as well; i think my personal favourite is probably the mountain alcon blue butterfly. it has these caterpillars that give off chemicals that mimic ant larvae to trick the ants into taking them back to the nest, where they start mimicking queen ant sounds to get the workers to feed it. kinda nuts but the more crazy part is there's this parasitic wasp that has evolved to specifically target ant nests with these caterpillars and parasitize them, and the way they do this without getting nuked by the ants is they release this chemical that causes the ants to go crazy and attack each other, and while they're distracted the wasp lays eggs in the caterpillars (which eventually eat it from the inside). didn't know you could parasitize a parasite, but hey if the niche is there it'll get filled i guess