Alienopteridae; Mesozoic; systematics; amber; palaeontology; palaeobiology

Alienoptera have been recently described from mid-Cretaceous amber and are nested phylogenetically inside the Dictyoptera lineage as the sister group of Mantodea. The second known species, Alienopterella stigmatica gen. et sp. nov., is described and illustrated in this contribution based on a male embedded in Cretaceous Burmese amber of earliest Cenomanian age. The well-preserved holotype allows clarification of the characteristics of the order. The first-studied hind wings are derived from the Dictyoptera ground plan. The membrane is transparent, veins are thickened and strongly sclerotized, and between C and SC2 is a conspicuous leathery lancet-shaped pterostigma. The wings are folded longitudinally back on the abdomen between the CuP and AA(1) veins in repose. The palaeobiology of Alienoptera is discussed based on the morphology of both known species. Alienopterans are inferred to have lived in trees or bushes with suitable foliage and were probably daytime active, visually oriented predators of small invertebrates.