Maternal care in a neotropical jumping spider (Salticidae)

Abstract

Although female jumping spiders (Salticidae) often stay with their egg sacs, little is known about whether this behaviour is effective in improving offspring survival. Females of the jumping spider Psecas chapoda (Salticidae) typically stay above their egg sacs and under a plain silk cover, spun from edge to edge of bromeliad leaves. The objective of this paper is to test the hypothesis that the presence of the females above the egg sac increases egg survival. We experimentally manipulated females and silk cover in P. chapoda using three treatments: female and silk cover present (control), female removed and silk cover present and female and silk cover removed. The number and area of holes in the egg sac walls, which are likely to be damage caused by egg predators, were higher in the absence of spiders and spiders+silk cover than in controls. Additionally, the number of spiderlings and exuvia was lower in the absence of females and female+silk cover than in the control treatment. The number of important specialized predators of spider eggs (i.e. mantipids) that develop inside P. chapoda egg sacs did not differ among the treatments. To our knowledge, this is the first experimental study that effectively demonstrates maternal care in spiders of the family Salticidae.