Figure 18. The systematics of A. amphitrite and C. diadema. Recent rDNA nucleotide study by Petrunina et al. (2013) suggests that Tantulocarida is closely related to the thecostracans and might even be nested within that class. However, it has not been confirmed. (AàB) indicates the change or the most updated systematics from the more widely used version. Although four new orders (Cyprilepadiformes, Ibliformes, Lepadiformes, Scalpelliformes) were erected by Buckeridge and Newman (2006), a more recent phylogenetic study by Pérez-Losada et al. (2008) continued the use the suborders within their analysis. Nonetheless, the newly erected orders are being increasingly used in recent studies (Ewers-Saucedo et al. 2019). (CàD) indicates the change suggested by a recent molecular work of Hayashi et al. (2013). They found that Coronuloidea is indeed monophyletic, but instead they identified four clades within Coronuloidea.