A new genus and species of scorpionfly (Mecoptera) from Baltic amber, with an unusually developed postnotal organ

A new genus and species of fossil scorpionflies (Mecoptera) Baltipanorpa damzenigen. et sp.n. is described from two well-preserved male specimens in Baltic amber (middle Eocene: Lutetian). The most characteristic feature of the new taxon is an unusually developed postnotal organ on abdominal tergum IV. This is the most extremely developed example of this organ among Mecoptera and the only observation of notal and postnotal organs among fossil scorpionflies. The following combination of characters are provided to distinguish the new genus from other Panorpidae: Sc, short; R1 and R2 two-branched; A1 joins posterior margin of wing only at same level as fork of vein Rs; unusual shape of abdomen, abdominal segments IIV strongly reduced, abdominal segment V elongate and widened, segments VII and VIII strongly elongate; notal and postnotal organs present, strongly developed process (postnotal organ) on tergum IV, unknown in all described extant and fossil scorpionflies. Different types of notal organs of Mecoptera are compared and their function and morphology are discussed. Morphological analysis of notal and postnotal organs in extant species permits us to conclude that B. damzenisp.n. is characterized by the most developed and complex notal organs in all Mecoptera.