New haidomyrmecine ants (Hymenoptera: Formicidae) from mid-Cretaceous amber of northern Myanmar

Abstract

Three new species and a new genus of “hell ants” (Haidomyrmecinae) are described from Cenomanian Burmese amber. Ceratomyrmex planus sp. nov. is the second species formally known for the genus and obliges a revision of the generic diagnosis. It can be recognized by its smaller size, the straight and shorter club-like cephalic horn, and flattened eyes. Haidomyrmex davidbowiei sp. nov. has only two trigger hairs on the apex of a brief clypeal lobe dorsal to the setal patch, the first flagellomere distinctly longer than the second, amongst other characters. Dilobops bidentata gen. et sp. nov., is the only known ant with a bidentate projection on the frontal region. Its clypeus is posteriorly flanked by two projecting lobes. The possible relation of the cephalic and mandibular morphology with the feeding habits of Haidomyrmecinae is discussed. It is argued that not all species impaled prey with their mandibles and that honeydew collection could have formed a part of their diet. A key for identifying the species of Haidomyrmex is included.