Summary1. Developing a predictive understanding of how species assemblages respond to fire is a key conservation goal. In moving from solely describing patterns following fire to predicting changes, plant ecologists have successfully elucidated generalizations based on functional traits. Using species traits might also allow better predictions for fauna, but there are few empirical tests of this approach. 2. We examined whether species traits changed with post-fire age for spiders in 27 sites, representing a chronosequence of 0-20 years post-fire. We predicted a priori whether spiders with ten traits associated with survival, dispersal, reproduction, resource-utilization and microhabitat occupation would increase or decrease with post-fire age. We then tested these predictions using a direct (fourth-corner on individual traits and composite traits) and an indirect (emergent groups) approach, comparing the benefits of each and also examining the degree to which traits were intercorrelated. 3. For the seven individual traits that were significant, three followed predictions (body size, abundance of burrow ambushers and burrowers was greater in recently burnt sites); two were opposite (species with heavy sclerotisation of the cephalothorax and longer time to maturity were in greater abundance in long unburnt and recently burnt sites respectively); and two displayed response patterns more complex than predicted (abdominal scutes displayed a U-shaped response and dispersal ability a hump shaped curve). However, within a given trait, there were few significant differences among post-fire ages. 4. Several traits were intercorrelated and scores based on composite traits used in a fourth-corner analysis found significant patterns, but slightly different to those using individual traits. Changes in abundance with post-fire age were significant for three of the five emergent groups. The fourthcorner analysis yielded more detailed results, but overall we consider the two approaches complementary. 5. While we found significant differences in traits with post-fire age, our results suggest that a traitbased approach may not increase predictive power, at least for the assemblages of spiders we studied. That said, there are many refinements to faunal traits that could increase predictive power.

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The Australian wolf spider genus Hoggicosa Roewer, 1960 with the type species Hoggicosa errans (Hogg, 1905) is revised to include ten species: Hoggicosa alfi sp. nov.; Hoggicosa castanea (Hogg, 1905) comb. nov. (= Lycosa errans Hogg, 1905 syn. nov.; = Lycosa perinflata Pulleine, 1922 syn. nov.; = Lycosa skeeti Pulleine, 1922 syn. nov.); Hoggicosa bicolor (McKay, 1973) comb. nov.; Hoggicosa brennani sp. nov.; Hoggicosa duracki (McKay, 1975) comb. nov.; Hoggicosa forresti (McKay, 1973) comb. nov.; Hoggicosa natashae sp. nov.; Hoggicosa snelli (McKay, 1975) comb. nov.; Hoggicosa storri (McKay, 1973) comb. nov.; and Hoggicosa wolodymyri sp. nov. The Namibian Hoggicosa exigua Roewer, 1960 is transferred to Hogna, Hogna exigua (Roewer, 1960) comb. nov. A phylogenetic analysis including nine Hoggicosa species, 11 lycosine species from Australia and four from overseas, with Arctosa cinerea Fabricius, 1777 as outgroup, supported the monophyly of Hoggicosa, with a larger distance between the epigynum anterior pockets compared to the width of the posterior transverse part. The analysis found that an unusual sexual dimorphism for wolf spiders (females more colourful than males), evident in four species of Hoggicosa, has evolved multiple times. Hoggicosa are burrowing lycosids, several constructing doors from sand or debris, and are predominantly found in semi-arid to arid regions of Australia.

Fire is a common disturbance in many ecosystems, including arid Australia. Understanding whether fauna respond in a deterministic manner towards a single end-point, or to multiple states, is of crucial importance for conservation management. Why different taxa or assemblages display single or multiple end-points is also important to develop a synthetic theory of succession. To examine the post-fire changes in assemblages of spiders, we established a chronosequence study in spinifex habitat of central Western Australia. Ground-active spiders were pitfall-trapped over nine months in sites representing experimental fires (0 and 0.5 years post-fire) and wildfires (3, 5, 8 and 20 years post-fire). There were significant non-linear changes in species richness, evenness and composition of spiders with increasing post-fire age. For all three measures, the assemblage appeared highly deterministic, converging towards the long unburnt state. Similarity in richness, evenness and species composition to the 20-year-old sites all increased with increasing time since fire (3-8 years). However, experimentally burnt sites did not neatly fit this sequence. We consider two alternative hypotheses to explain this second trajectory: inertia within the system or the rapid migration and recolonization from nearby surrounding unburnt areas. Analyses indicated that half of the 179 species had significant preferences for, or were restricted to, particular post-fire ages. This suggests that adequate pyrodiversity, both in terms of post-fire ages and/or scale and intensity of fires, may be important for the conservation of spiders in this habitat. However, owing to the high number of singletons and low indicator values, the significance of this result for conservation management remains equivocal. Despite this, the high degree of determinism provides hope that managers can develop a good predictive understanding of post-fire successional changes in spider assemblages in arid Australia.

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