Abstract: | The genus Antennocheles gen. nov. is based on adults and nymphs of two newly described species associated with hispine beetles of the genera Chelobasis and Cephaloleia occupying unfurled leaves of Heliconia in lowland rainforest of Costa Rica. Within the superfamily Ascoidea, this taxon is so distinctive morphologically and behaviourally as to justify its own family, Antennochelidae, fam. nov. These mites bear remarkably elongated cheliceral shafts, which may extend for lengths greater than the body but are fully ensheathed in repose within the body. Other unique attributes include linear arrangement of hypostomatic setae, a pore-like structure beside the corniculus, and adults with a pair of unique sternal invaginations for enlarged muscle insertions. While undergoing their life history in water films of unfurled host leaves, the mites exhibit a slow, swimming-like behaviour in quest for prey. As leaves unfurl, adult mites run quickly off and on their hispine beetle phoronts for dispersal.http://zoobank.org/urn:lsid:zoobank.org:pub:0876014C-1433-463B-B1A4-4CD6886F9D28 |