|Xenognath type of polychaete jaw apparatuses
Piotr Mierzejewski & Grażyna Mierzejewska
Acta Palaeontologica Polonica 1975, 20, 3, 437-444
|[abstract, p. 437]
A new type of ?eunicid jaw apparatuses designated xenognath is described; it differs from previously known jaw apparatuses in having the denticulated ridges in compound jaws perpendicular to apparatus axis. It includes the Ordovician genus Archaeoprion nov., assigned to a new family Archaeoprionidae.
|Archaeoprion quadricristatus Mierzejewski & Mierzejewska, 1975|
|Nearly complete jaw apparatus devoid of ridges IV; venral view of the right jaw and lateral view of the left one.|
|Specimen derived from the erratic boulder (Baltic coast, Caradoc).|
| Diagnosis (p. 441) of Archaeoprion:
Almost triangular, plate-like compound jaws. Each jaw with four denticulated ridges. Denticulated ridge I lowermost, sometimes smooth. Denticulated ridge IV with chisel teeth. Pseudocarrier delicate, longer than jaws.
|Dimensions of the holotype: lenght 0.355 mm, width 0.178 mm.|
|left compound jaw|
|right compund jaw|
|Dorsal view of the xenognath jaws apparatus|