Ptychopariida

Inkouia jiangshanensis

Order Ptychopariida / Suborder Olenina / Family Olenidae

Tremadocian (Early Ordovician)Zhejiang

Inkouia jiangshanensis — photo 1 — Photo 1 · Holotype TK046 and 047, part and counterpart (Zhejiang; Han Nairen 1983) Cranidium and pygidium with the last two thoracic segments (Zhejiang; Han Nairen 1983)

Inkouia jiangshanensis — photo 2 — Photo 2 · Holotype TK046 and 047, part and counterpart (Zhejiang; Han Nairen 1983) Cranidium and pygidium with the last two thoracic segments (Zhejiang; Han Nairen 1983)

Classification

Order Ptychopariida / Suborder Olenina / Family Olenidae

Genus

Inkouia Chang & Fan, 1960

Genus author

Zhang Wentang, Fan Jiasong

Genus etymology

Inkou, Yingou within the Angzanggou west of Yumen City, Gansu

Species

I. jiangshanensis Han, 1983

Species author

Han Nairen

Species etymology

Jiangshan, Jiangshan, Zhejiang, the locality

Age

Tremadocian (Early Ordovician)

Distribution

Zhejiang

Diagnosis

Glabella convex, subsquare, with three pairs of glabellar furrows, S1 and S2 narrow and deep, nearly parallel, S3 faint; preglabellar field longitudinally short; anterior border narrow; occipital furrow deep, slightly recurved medially; occipital ring of uniform longitudinal length; fixigenae narrow in the palpebral area; eye ridges short; palpebral lobes medium; librigenae narrow with long genal spines. Thorax of 14 segments; axis wide, narrowing backward, segment 12 with a long axial spine, the remaining segments each with a median node; pleural furrows deep, pleural ends truncate. Pygidium semi-elliptical; axis with 4 rings, reaching the border; pleural and interpleural furrows distinct; border narrow.