Punk’s not dead? Punkochyzeria gen. nov. (Acari: Chyzeriidae) from Cretaceous Myanmar amber

We report the discovery of remarkable fossil mites referred to a new genus Punkochyzeria gen. nov. (Trombidiformes: Chyzeriidae) found in mid-Cretaceous Kachin amber from Myanmar. The postlarval stages of these mites possess unusually long tufts of dorsal opisthosomal setae. The mites were initially identified as Parachyzeria Hirst, 1926, but detailed morphological analysis revealed several key characters, including the absence of a paradont or basidonts on the palptibia, suggesting a new genus. We describe three new species, Punkochyzeria minaevi sp. nov., Punkochyzeria makolae sp. nov. and Punkochyzeria khoyi sp. nov., which are distinguished by the form of the dorsal opisthosomal setae, the odontus/palptarsus ratio and the number of setae on the palptibial ctenidium. We also present an identification key to the species of the genus Punkochyzeria and describe four specimens of this genus, which are difficult to attribute to any particular species, because of their poor state of preservation. We discuss the erectile function of the long dorsal setae. Notably, the individuals of P. makolae and P. khoyi carry other mites as syninclusions among the long tufts of setae, although phoretic relationship may be accidental. This discovery extends the known diversity of the family Chyzeriidae to the Cretaceous and provides new insights into their evolutionary history and ecological interactions.