Akoldinioidia dydimacantha

Order Ptychopariida / Suborder Ptychopariina / Superfamily Ptychoparioidea / Family Shumardiidae

a-, against, not, away from, without; Koldinioidia, a trilobite genus name

dydim-, dydimos, Greek, double; acantha, Greek, spine, referring to the macropleural spines of the thorax

Glabella slightly convergent anteriorly with blunt-pointed front; occipital ring large, transversely triangular, with a small occipital node at its centre; fixigenae short in front of the eyes. Thorax of 6 segments; axis narrowing abruptly after the third axial ring; segments 3 and 4 are macropleural with long, backward-extending spines. Pygidium transversely wide; axis with 3 rings and a terminal piece; pleural furrows and pleural ribs distinct.