1913 Protornoceras mirabile Dybczynski: 514, pl.2 fig.4.
1970 Tornia mirabile.-House, p.672, pl.126 fig.3-5, text-fig.2A.
2002 Tornia mirabilis.-Korn & Klug: 165, Fig.150 B, F.

see Fig. TAX1359 A (suture).

Open umbilicate, with ventral siphuncle, biconvex growth-lines.

Suture forming a broad shallow lateral lobe, a narrow ventral lobe and a deep linguiform dorsal lobe.

"Morphologically this form is identical with some platyclymenids apart from the ventral position of the siphuncle. Relic traces of the typical tornoceratid adventitious lobe can be seen in the broad lateral lobe, but this cannot be crossed by a radial line drawn from the umbilicus and in this respect differs from the presumed Protornoceras antecedents ... and there is no arched lateroumbilical saddle as is also characteristic of tornoceratids. The genus closely approaches homeomorphy with the Middle Devonian genus Agoniatites." (House, 1970, p. 671).