What family did the yellow sac spider historically belong to before modern molecular investigation prompted reclassification?

Clubionidae

For a significant period of arachnid classification history, spiders now subject to molecular scrutiny, including the common yellow sac spider group, were categorized under the family Clubionidae. This historical placement was based primarily on observable external characteristics, or morphology, which scientists now recognize were insufficient indicators of deep evolutionary relationships. The subsequent application of molecular tools revealed that the lineage splitting events were much older and more complex than the external similarities suggested, leading to the establishment of distinct taxonomic groupings outside of the traditional Clubionidae structure for many of these pale spiders.