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Webs play many essential roles in spider biology, including communication, prey capture, locomotion, and reproduction. One interesting morphological feature of many spiders is the cribellum, a plate located near the silk-producing structures called spinnerets, and used to create a special type of matted silk that captures prey mechanically, instead of with glue droplets used by many orb-weaving spiders. The cribellum is hypothesized to have been present in the ancestor of all araneomorph spiders, but lost multiple times over the course of spider evolution. One group of spiders, the ‘marronoids’, shows a pattern of repeated loss and gain of this structure, placing them at a transitional position in the evolution of spider webs, with further implications for the web capture strategy, and other ecological conditions such as water-associated habitat. Studying the timing of the loss of the cribellum may yield insight to the cryptic ecology and morphology of the marranoid clade, and more broadly, araneomorph spiders. We use comparative phylogenetic methods to identify ancestral states of morphological and behavioral characters, and examine divergence dates with fossil calibrations. To do this, 98 representative spiders from the marronoid clade were coded by zoogeographic region, distribution proximity to a body of water and type, web type, and observed aquatic behavior. The morphology of the cribellum and spinnerets was assessed using 42 characters with multiple states. We identified patterns of evolution of the cribellum and aquatic habitat associations in the context of phylogeny, and geologic time.