Systematics and natural history of Uaitemuri, a new genus of the orb-weaving spider family Uloboridae (Araneae: Deinopoidea) from south-eastern Brazil

摘要

We describe a new genus and two new species of the spider family Uloboridae Thorell, 1869 from south-eastern Brazil. Uaitemuri gen. nov. can be distinguished by the peculiar shape of the opisthosoma, the presence of flattened setae on the patella and tibia of all legs, the flattened embolus, presence of a tegular plate in the male palpus, and female genitalia with flattened copulatory ducts associated with inflated hyaline copulatory atria. The type species, Uaitemuri rupicola sp. nov., is described from males and females from lowland and montane forests throughout south-eastern Brazil. A second species, Uaitemuri demariai sp. nov., is based on a single male from a coastal forest in the state of Sao Paulo. Morphological and behavioural data support the monophyly of the genus and suggest it is closely related to Orli-lomat-la Strand, 1934, Polertecia Lehtinen, 1967, Hyptiotes Walckenaer, 1837, and Miagrammopes 0, Pickard-Cambridge, 1870. Uaitemuri rupicola builds vertical orb webs with a spiral-free sector, as observed in some species of Araneidae and Tetragnathidae, but recorded here for the first time in Uloboridae. The pteromalid wasp Arachnopteromalus dasys Gordh, 1976 was observed attacking egg sacs in a population of U. rupicola.