Descriptions of a new species and the gyne in the rarely collected arboreal genera Paratopula and Rotastruma (Hymenoptera: Formicidae) from Hong Kong, with a discussion on their ecology

Despite its relatively large size among the Myrmicinae of the Indomalayan region, collection events of Paratopula Wheeler are rare. Here we discuss the discovery of Paratopula in Hong Kong and present Paratopula bauhinia sp. nov as a new species. This addition brings the number of globally described species for the genus to twelve species, four of which are known only from the reproductive caste. Paratopula bauhinia sp. nov . can be distinguished from previously described species by the combination of the following features: 10 teeth on the masticatory margin of mandibles, apically acute hairs, a rounded median portion of the anterior margin of the pronotum, postpetiole broader than long, and straight, blunt propodeal spines. A revised key for the eight species of Paratopula known from the worker caste is provided. Additionally, the female caste of Rotastruma stenoceps Bolton is described for the first time. The rarity of these two genera are also discussed on the basis of their potentially nocturnal and arboreal habits.