mentioned (under Ranunculus aquatilis, "var. a. native to Eurasia"), but not indicated for California in The Jepson Manual [Ed. 1]; in no way mentioned in Kartesz & Meacham
Correspondence and Comments Subsequent to Initial Analysis
Correspondence 1 indicates that Alan T. Whittemore, in Flora North America 3:132 (1997), includes Ranunculus aquatilis L. var. hispidulus as a synonym of Ranunculus aquatilis L. var. aquatilis.
Correspondence 2 confirms that for The Jepson Manual [Ed. 2] Ranunculus aquatilis L. var. hispidulus Drew is to be treated as a synonym of Ranunculus aquatilis L. var. aquatilis.