Thanks Sebastian!
Yes in the first edition of Genera Palmarum they were placed in the Arecoideae based on the similarities in the inflorescence anatomy of Caryoteae and Iriarteeae. In 2006 however this molecular study http://onlinelibrary.wiley.com/doi/10.1111/j.1095-8339.2006.00521.x/abstract showed that they actually belong within Coryphoideae. Another major change with that study was the new placement of Chamaedoreeae within Arecoideae with Chamaedorea, Hyophorbe, Gaussia, Synechanthus and Wendlandiella. It was formerly Hyophorbeae within Ceroxyloideae. That is the classification that also was used in the second edition of Genera Palmarum.