Three new species of mouse spider (Araneae: Actinopodidae: Missulena Walckenaer, 1805) from Western Australia, including an assessment of intraspecific variability in a widespread species from the arid biome

Abstract

Mouse spiders (genus Missulena Walckenaer, 1805) are a lineage of trapdoor spiders with males of many species having a brightly coloured red cephalic region, an abdomen that is tinged metallic blue, and the habit of wandering during the day in search of a mate. A total of 17 species of Missulena have been described in Australia to date but most descriptions are based exclusively on males and always small numbers of specimens. Here, we describe three new species of Missulena from the Pilbara and Goldfields regions of Western Australia based on morphology and genetic data: Missulena davidi sp. nov. (male and female), M. iugum sp. nov. (male) and M. manningensis sp. nov. (male). One of them is presently known only from its type locality and another one from a small range based on two specimens but M. davidi sp. nov. has a linear range of almost 300 km and is genetically highly structured. We use genetic data for 75 specimens as a foundation to evaluate morphological variability in this species and note substantial variation in several characters commonly used to identify species such as body size, colouration, rastellum shape and eye distances. This variation does not necessarily relate to phylogeographic structure as inferred from the genetic data, but rather seems to reflect natural variability both within and between localised populations. Overall, our results stress the need to evaluate a large series of specimens for mygalomorph taxonomy and provide an interesting example of intraspecific variability in hard-to-collect species that are usually underrepresented in museum collections.