Balticalcarus archibaldi Simutnik Gen. et sp. n. (Chalcidoidea, Encyrtidae) with the Unusually Small Mesotibial Spur from Baltic Amber

Balticalcarus archibaldi Simutnik, gen. et sp. n., is described and illustrated based on a female specimen from late Eocene Baltic amber. The new genus is characterized by the absence of a filum spinosum, a “boat”-shaped hypopygium enclosing the ovipositor, reaching far past the apex of the syntergum, the presence of a line of long setae along the entire costal cell of the hind wing, and a transverse line of thickened setae alongside the hyaline spur vein. Moreover, like most previously described Eocene Encyrtidae, the new taxon differs from the majority of the extant ones by a number of morphological features. The new fossil differs from most extant and all known fossil Encyrtidae by its unusually small, thin, smooth (without microsetae) mesotibial spur.