...Figure 1. Generalized reconstruction and cross section of Totiglobus nimius based on fossil evidence. A) External view from side (modified from Bell and Sprinkle, 1978 ). B) Cross section through reconstruction. Black arrow points to oral frame plate. Gray arrow points to basal disk plate...

... plating. In one important aspect, the holotype and referred specimens complement each other with regard to interpretation of the cover-plate configuration (see the preceding). Biserial ambulacral floor-plate morphology resembles those of S. lloydi , Totiglobus nimius Bell and Sprinkle, 1978...

... Pompeckj, 1896 ) and edrioasterid edrioasteroid ambulacra, where similar plates are embedded into the body wall of the primary thecal cavity (e.g., the middle Cambrian Totiglobus nimius Bell and Sprinkle, 1978 , and later Ordovician taxa, such as edriosterid sp. of Guensburg and Sprinkle, 1994 ; see...

... rather than being aligned (Sumrall et al., 2013 ). Interestingly, these aboral structures are demonstrably absent from the middle Cambrian taxon Totiglobus nimius . Here, the base of the theca is a circular structure plated on the outside by a flat radial array of small...

..., the early edrioasterid Totiglobus nimius Bell and Sprinkle 1978 , Middle Cambrian, ambulacral segments; 5, NYSM 13313, cover plates intact, lateral floor plate extensions; 7, NYSM 13303, cover plates missing, floor plates exposed showing furrow, podial pores, lateral extensions, compare...

...Figure 1 —Comparison of thecal morphology between the major clades of edrioasteroids. 1 , the edrioasterid Edrioaster bigsbyi (Billings) showing a globular theca and a short pedunculate zone; 2 , The totiglobid Totiglobus nimius Bell and Sprinkle showing a globular theca lacking...