The monophyly of Conchifera is supported by molecular phylogenetic analysis.[1] The relationships among the members of Conchifera are disputed.[1] A grouping of Scaphopoda and Bivalvia, named Diasoma, has been proposed,[3][4] but other studies find scaphopods to be more closely related to cephalopods[5] or gastropods.[1]
^ abSong, Hao; Wang, Yunan; Shao, Haojing; Li, Zhuoqing; Hu, Pinli; Yap-Chiongco, Meghan K.; Shi, Pu; Zhang, Tao; Li, Cui; Wang, Yiguan; Ma, Peizhen; Vinther, Jakob; Wang, Haiyan; Kocot, Kevin M. (2023-10-03). "Scaphopoda is the sister taxon to Bivalvia: Evidence of ancient incomplete lineage sorting". Proceedings of the National Academy of Sciences. 120 (40): –2302361120. doi:10.1073/pnas.2302361120. eISSN1091-6490. hdl:1983/edbbfb14-28f5-47ae-9189-ed00112ad1db. ISSN0027-8424. PMID37738291.
^Steiner, Gerhard; Dreyer, Hermann (2003). "Molecular phylogeny of Scaphopoda (Mollusca) inferred from 18S rDNA sequences: support for a Scaphopoda–Cephalopoda clade". Zoologica Scripta. 32 (4): 343–356. doi:10.1046/j.1463-6409.2003.00121.x. eISSN1463-6409. ISSN0300-3256.