Dispersal Strategies, Genetic Diversity, and Distribution of Two Wolf Spiders (Araneae, Lycosidae): Potential Bio-Indicators of Ecosystem Health of Coastal Dune Habitats of South America

Abaycosa a new genus of South American wolf spiders (Lycosidae: Allocosinae)

“…In the same way, the environment could explain the morphological differences between Abaycosa and other South American species of the subfamily, such as Allocosa senex, which presents a divergent morphology related to a specialization to live in sandy substrates, such as elongated spinnerets, long and thin pedipalps with specialized macrosetae, large chelicerae, and a high prosoma (Aisenberg et al 2010;Foelix et al 2017;Simó et al 2017;Albín et al 2018). The present study contributes to establishing a phylogenetic framework of the subfamily, necessary to study how some interesting behavior traits evolve in species of the subfamily such as A. senex and A. marindia (Bidegaray-Batista et al 2017), which shows a reversal in the typical sex roles and size dimorphism of spiders (Aisenberg et al 2007;Aisenberg and Costa 2008;Aisenberg 2014). Future studies will focus on expanding this phylogenetic framework, including more taxa of Allocosinae from South America and the North American species of the genus Allocosa, in order to determine the diversity of genera and species within the subfamily and their relationships to each other.…”

Ground-Dwelling Arachnids and Fire Disturbance: A Case Study in Northeastern Patagonia (Argentina)

“…Many arachnids have high efficiency as colonizers of disturbed sites [65]. Spiders can disperse to nearby environments by ambulatory locomotion or reach higher distances through the air through silk threads ("ballooning") [14,66]. This could explain why the most evident changes in arachnid richness and diversity usually occur during the first year after the fire [19,57].…”

Eight‐legged swimmers: Behavioral responses to floods in two South American spiders

“…Furthermore, females of A. senex and A. marindia showed higher "swims" events than males. In both species, the females construct shorter burrows than males, which exposes them more quickly and dramatically to the water currents when facing sudden flood events (Aisenberg, 2014;Bidegaray-Batista et al, 2017). These facts would imply a more intense pressure on this sex to be better swimmers than males.…”

“…Divergences in the microhabitat and in the distance to the shoreline between species could be shaping these differences. Allocosa senex is found closer to the shore, in open dunes with scarce vegetation (Bidegaray‐Batista et al, 2017; Ghione et al, 2013), areas which are much more prone to floods, whereas A . marindia inhabits behind the foredune, in areas with native and exotic vegetation that could offer natural anchorage when facing sudden floods.…”

“…Divergences in the microhabitat and in the distance to the shoreline between species could be shaping these differences. Allocosa senex is found closer to the shore, in open dunes with scarce vegetation(Bidegaray-Batista et al, 2017;Ghione et al, 2013), areas which are much more prone to floods, whereas A. marindia inhabits behind the foredune, in areas with native and exotic vegetation that could offer natural anchorage when facing sudden floods. We observed in both Allocosa species that when the water entered the burrows, individuals reinforced the burrow walls with silk, and their bodies looked as if they were covered with air bubbles.Immersion tolerance and subsequent flood survival observed in this study for A. senex and A. marindia have also been reported byStratton et al (2004) in the wolf spider Pardosa lapidicina andRovner (1987) for the spiders Dysdera crocata and Ariadna bicolor.These last species are able to survive the floods by remaining within their nests for up to 10 days.…”