Denver Museum of Nature and Science, Denver, Colorado, USA

Holotype DMNH-26516 for Orontium wolfei Bogner, K.R.Johnson, Kvaček et Upchurch

Holotype DMNH 6711 for Symplocarpus hoffmaniae Bogner, K.R.Johnson, Kvaček et Upchurch

Holotype DMNH24819 for Cobbania hickeyi Stockey, G.W.Rothwell et K.R.Johnson