Diplorrhina

Mesospheniscus Diplorrhina Hawle and Corda (1847) [2] is a genus of trilobite belonging to Order Agnostida.

It lived during the early Middle Cambrian (Amgan and Mayan stages) in what are now the Czech Republic and the North Siberian plateau.

D. recta is the most primitive species and it gave rise to D. cuneifera, which was in turn ancestral to Diplorrhina triplicata.

The pygidial border is flattened and wide with posterolateral angles, but no spines.

[3] Diplorrhina differs from members of the subgenus Peronopsis (Peronopsis) in the better developed transaxial furrows, better developed lateral furrows of the glabella, larger basal lobes, and in the trend towards the formation of a transverse depression of the axis.

Schematic showing the relationship between the genus *Diplorrhina* (light green) with other Peronopsid genera (darker green).