Asaphida

Ampyx priscus

Order Asaphida / Superfamily Trinucleoidea / Family Raphiophoridae

Tremadocian (Early Ordovician)Morocco
Ampyx priscus — photo 1
Photo 1 · (Morocco; Vannier et al., 2019) Literature specimens showing queuing migration Migrating specimens of two intersecting lines (Morocco; Vannier et al., 2019) Complete dorsal exoskeleton (Morocco; (Morocco; Haiyang Wangzi) Pengcheng Jianke)
Ampyx priscus — photo 2
Photo 2 · (Morocco; Vannier et al., 2019) Literature specimens showing queuing migration Migrating specimens of two intersecting lines (Morocco; Vannier et al., 2019) Complete dorsal exoskeleton (Morocco; (Morocco; Haiyang Wangzi) Pengcheng Jianke)
Ampyx priscus — photo 3
Photo 3 · (Morocco; Vannier et al., 2019) Literature specimens showing queuing migration Migrating specimens of two intersecting lines (Morocco; Vannier et al., 2019) Complete dorsal exoskeleton (Morocco; (Morocco; Haiyang Wangzi) Pengcheng Jianke)
Ampyx priscus — photo 4
Photo 4 · (Morocco; Vannier et al., 2019) Literature specimens showing queuing migration Migrating specimens of two intersecting lines (Morocco; Vannier et al., 2019) Complete dorsal exoskeleton (Morocco; (Morocco; Haiyang Wangzi) Pengcheng Jianke)
Classification
Order Asaphida / Superfamily Trinucleoidea / Family Raphiophoridae
Genus
Ampyx Dalman, 1827
Genus author
Dalman J. W.
Genus etymology
ampyx, a headband, a round object
Species
A. priscus Thoral, 1935
Species author
Thoral M.
Species etymology
priscus, former, primitive
Age
Tremadocian (Early Ordovician)
Distribution
Morocco
Diagnosis
Dorsal shield ovate. Cephalon subtriangular to semicircular; glabella narrow, expanding forward, extended into a long spine-like protuberance; fixigenae wide; eyes absent; librigenal genal spines very long, exceeding the body length twice. Thorax of 6 segments; axis slightly narrower than pleurae; pleurae straight, pleural spines absent. Pygidium nearly semicircular; axis short; pleural and interpleural furrows of the pleural region both extremely shallow.
Remarks
In 2019, Vannier et al. reported a study of the collective "queuing" migratory behaviour of this species.