Phacopida

Coronocephalus nanjingensis

Order Phacopida / Suborder Cheirurina / Superfamily Cheiruroidea / Family Encrinuridae / Subfamily Coronocephalinae

Telychian (Llandovery, Silurian)Jiangsu

Coronocephalus nanjingensis — photo 1 — Photo 1 · Type specimen figures (Jiangsu; left: Lin Tianrui 1982; right: colour figure, source unknown, NIGP collection) Complete dorsal exoskeleton (Jiangsu; left: exoskeleton; middle: external mould; right: enlargements of librigenae and pygidium; Heidou Kedou)

Coronocephalus nanjingensis — photo 2 — Photo 2 · Type specimen figures (Jiangsu; left: Lin Tianrui 1982; right: colour figure, source unknown, NIGP collection) Complete dorsal exoskeleton (Jiangsu; left: exoskeleton; middle: external mould; right: enlargements of librigenae and pygidium; Heidou Kedou)

Coronocephalus nanjingensis — photo 3 — Photo 3 · Type specimen figures (Jiangsu; left: Lin Tianrui 1982; right: colour figure, source unknown, NIGP collection) Complete dorsal exoskeleton (Jiangsu; left: exoskeleton; middle: external mould; right: enlargements of librigenae and pygidium; Heidou Kedou)

Coronocephalus nanjingensis — photo 4 — Photo 4 · Type specimen figures (Jiangsu; left: Lin Tianrui 1982; right: colour figure, source unknown, NIGP collection) Complete dorsal exoskeleton (Jiangsu; left: exoskeleton; middle: external mould; right: enlargements of librigenae and pygidium; Heidou Kedou)

Coronocephalus nanjingensis — photo 5 — Photo 5 · Type specimen figures (Jiangsu; left: Lin Tianrui 1982; right: colour figure, source unknown, NIGP collection) Complete dorsal exoskeleton (Jiangsu; left: exoskeleton; middle: external mould; right: enlargements of librigenae and pygidium; Heidou Kedou)

Classification

Order Phacopida / Suborder Cheirurina / Superfamily Cheiruroidea / Family Encrinuridae / Subfamily Coronocephalinae

Genus

Coronocephalus Grabau, 1924

Genus author

Grabau A. W.

Genus etymology

coron (Latin, crown) + cephal- (Greek, head), referring to the crown-like border of the librigenae

Species

C. nanjingensis Lin, 1982

Species author

Lin Tianrui

Species etymology

Nanjing, Nanjing, Jiangsu, type locality of the type specimens

Age

Telychian (Llandovery, Silurian)

Distribution

Jiangsu

Diagnosis

Cephalon semicircular. Cranidium covered with nodes; anterior glabellar lobe large, 3 pairs of transglabellar furrows; dorsal furrows wide and deep; fixigenae narrow, stout long genal spines from the genal angles, with small triangular lateral spines at the base of the genal spines; librigenal border with 9 tooth-like spines; eyes large, kidney-shaped. Thorax of 11 segments, segment 7 macropleural with a large backward-extending spine. Pygidium triangular; axis with 30-35 rings, pygidial pleural segments 13; pygidial pleural spines short.

Remarks

This species closely resembles the type species Coronocephalus rex, differing mainly in the shape of the posterior pygidial pleural segments and in the narrower, shallower thoracic and pygidial axial furrows.