Asaphida

Symphysurus ebbestadi

Order Asaphida / Superfamily Cyclopygoidea / Family Nileidae

Tremadocian (Early Ordovician)Morocco

Symphysurus ebbestadi — photo 1 — Photo 1 · García-Bellido D. C. Holotype MGM-7015X (Morocco; Gutiérrez-Marco et al., 2019) Paratypes MGM-7016X & 7017X (Morocco; Gutiérrez-Marco et al., 2019) Slab specimen (Morocco; Gutiérrez-Marco et al., 2019) (Morocco; Laibl et al., 2023)

Symphysurus ebbestadi — photo 2 — Photo 2 · García-Bellido D. C. Holotype MGM-7015X (Morocco; Gutiérrez-Marco et al., 2019) Paratypes MGM-7016X & 7017X (Morocco; Gutiérrez-Marco et al., 2019) Slab specimen (Morocco; Gutiérrez-Marco et al., 2019) (Morocco; Laibl et al., 2023)

Symphysurus ebbestadi — photo 3 — Photo 3 · García-Bellido D. C. Holotype MGM-7015X (Morocco; Gutiérrez-Marco et al., 2019) Paratypes MGM-7016X & 7017X (Morocco; Gutiérrez-Marco et al., 2019) Slab specimen (Morocco; Gutiérrez-Marco et al., 2019) (Morocco; Laibl et al., 2023)

Symphysurus ebbestadi — photo 4 — Photo 4 · García-Bellido D. C. Holotype MGM-7015X (Morocco; Gutiérrez-Marco et al., 2019) Paratypes MGM-7016X & 7017X (Morocco; Gutiérrez-Marco et al., 2019) Slab specimen (Morocco; Gutiérrez-Marco et al., 2019) (Morocco; Laibl et al., 2023)

Classification

Order Asaphida / Superfamily Cyclopygoidea / Family Nileidae

Genus

Symphysurus Goldfuss, 1843

Genus author

Goldfuss A.

Genus etymology

symphy-, Greek, glued together

Species

S. ebbestadi Gutiérrez-Marco, Rábano & García-Bellido, 2019

Species author

Gutiérrez-Marco J. C., Rábano I. &

Species etymology

Ebbestad, a surname, in honour of the Norwegian palaeontologist Jan Ove Røysi Ebbestad (Uppsala University, Sweden), author of works on Scandinavian Symphysurus

Age

Tremadocian (Early Ordovician)

Distribution

Morocco

Diagnosis

Cephalon and pygidium both semi-elliptical, surface densely covered with interwoven finger-print-like terrace lines. Glabella large, widening anteriorly, without glabellar furrows; dorsal furrows deep; occipital furrow weak or indistinct; palpebral lobes large, at the middle of the cranidium; librigenae small with rounded genal angles. Thorax of 8 segments; axis narrower than pleurae; pleural spines absent. Pygidial axis faint, short-conical; pleural region smooth; pygidial border absent.