Palaeozygopleura chlupaci Frýda, 1993

Holotype. UUG JF 50 (Frýda 1993: figs 2.1–2.3, 2.6, 2.7).

Paratypes. UUG JF 51–54 (Frýda 1993: figs 2.5, 2.6).

Type locality. Koukolová Hora hill near Beroun, Barrandian area, central Bohemia (49°55'18.346"N, 14°1'13.357"E).

Type horizon. Monograptus uniformis graptolite Biozone, Early Lochkovian, Early Devonian.

Remarks. Palaeozygopleura chlupaci is hitherto the oldest species of the genus. The first occurrence of Palaeozygopleura is connected with a period of global increase of δ13C in the marine ecosystem, known as the Klonk Event (Manda & Frýda 2010), which was followed by a rapid occupation of the free water column by different animal groups, an increase of free-swimming predators as well as distinct changes in the plankton composition (Nützel & Frýda 2003; Berkyová et al. 2007; Klug et al. 2010).

Stratigraphic and geographic distributions. Besides from its type locality and the "Nad roklí" section near Černá rokle Gorge (SW Prague; Frýda & Manda 1997), this species has been newly recorded from the Pod Kotýsem section (W of the village of Konĕprusy).