Scanning electron microscopy of Sarcoptes kutchensis, a new species of a Middle Eocene sarcoptid mite in amber from the Umarsar Lignite Mine of Kutch, Western India

Abstract

ABSTRACT The article describes a new species of a fossil sarcoptid mite, Sarcoptes kutchensis n. sp. extracted from a dissolved slab of amber, from the Umarsar Lignite Mine of the Kutch Basin. The fossil is a remarkable representative of forest litter biota, well-preserved in amber and represents the oldest group of mites from the equatorially placed Eocene forest, dominated by broad-leaved Dipterocarpaceae trees and shares similar taxonomic features with the present day genus of Sarcoptes, Latreille, 1802. The species is recognised by dense microfoveolate striations, lack of cuticular spines on the dorsal surface with morphological resemblance to Trixacarus, Sellnick, 1944, particularly in terms of monodactyly. The fossil is derived from an ancient group of forest litter biota which gradually evolved to higher trophic levels including association with vertebrates. Scanning Electron Microscopy (SEM) is used to highlight diagnostic characteristics including capitulum and partially concealed legs with sensory suckers, crucial for defence against large faunal predators.