The pliomerid trilobite Ibexaspis and related new genera, with species from the Early Ordovician (Floian; Tulean, Blackhillsian) of the Great Basin, western USA Author E. B, Neo Author Adrain, Jonathan M. Author Karim, Talia S. text Zootaxa 2018 2018-11-27 4525 1 1 152 journal article 27906 10.11646/zootaxa.4525.1.1 aab5d525-1d70-4a48-9469-43d4e446685d 1175-5326 2610805 9D378750-982F-4061-A419-B28E8DDFF825 Deltapliomera n. sp. A Plate 21 , figs 22–26 2009 Ibexaspis sp. nov. 5 ( partim ); Adrain et al ., p. 569, fig. 16L (only; fig. 16P = Deltapliomera heimbergi n. sp. ). Material. Assigned specimen SUI 115308 from Section H 172.5T m, Fillmore Formation (Floian; Tulean; Panisaspis sevierensis Zone), southern Confusion Range, Ibex area, Millard County, western Utah , USA . Discussion. A single cranidium differs from the co-occurring species D. heimbergi (cf. Pl. 21, fig. 22 with Pl. 23, fig. 1) by being broader, less strongly vaulted (tr., sag.) both axially and from less strongly downturned fixigenae; in possessing considerably finer, denser tuberculate sculpture; narrower interocular fixigenae; narrower palpebral lobes; a more parallel-sided, not forwardly-expanding, glabella that is broader at the base and has a larger, more transversely oriented L1, and a slightly smaller L3 and shallower S3; slightly shorter SO; longer, wider, more effaced LO; longer (especially adaxially) and a less tuberculate posterior border. Deltapliomera heimbergi occurs separately from Deltapliomera n. sp. A at H 166.2 m and at H 173.2 m.