The genus Ardea includes all living species of large herons. Brodkorb (1963) listed five fossil species of Ardea, and only one fossil species has since been described. Of these six, only two are unquestionably members of the genus Ardea. Ardea brunhuberi von Ammon, 1918, from the Upper Miocene Brown Coal Formation, Württemburg, Germany, was moved by Brodkorb (1980) to the Phalacrocoracidae as Phalacrocorax brunhuberi. Brodkorb (1980) considered A. lignitum Giebel, 1860, from the Sarmatian Brown Coal of Rippersroda, Thuringia, Germany, to be a large owl in the genus Bubo. Olson (1985) similarly regards A. perplexa from the Astaracian of Sansan, France, to be a large owl, possibly in the genus Bubo. The type of Ardea aureliensis Milne-Edwards, 1871, from the Oreleanian of Suevres, France, has never been illustrated or restudied and its affinities need to be confirmed (Olson, 1985). The valid fossil species are Ardea polkensis Brodkorb, 1955, from the late Hemphillian Bone Valley Mining District, Florida, and A. howardae Brodkorb, 1980, from the Plio/Pleistocene Shungura Formation, Omo Basin, Ethiopia. A large species of Ardea is also known from the late Clarendonian Love Bone Bed local fauna, Florida, but is based on material too fragmentary for specific identification (Becker, 1985). This note reports the earliest certain occurrence of Ardea now known.
Comparison between the Middle Miocene and the Upper Miocene source rock formations in the Sava Depression (Pannonian Basin, Croatia)
