Phacopida

Calymenesun tingi

Order Phacopida / Suborder Calymenina / Superfamily Calymenoidea / Family Calymenidae

Darriwilian to Sandbian (Middle to Late Ordovician)Guizhou

Calymenesun tingi — photo 1 — Photo 1 · palaeontologist Cranidium, pygidium and hypostome specimens Lectotype NIGP 3455 (Guizhou; Lu Yanhao 1975) (Guizhou; Zhou et al., 1984) (Guizhou; Zhou et al., 1984)

Calymenesun tingi — photo 2 — Photo 2 · palaeontologist Cranidium, pygidium and hypostome specimens Lectotype NIGP 3455 (Guizhou; Lu Yanhao 1975) (Guizhou; Zhou et al., 1984) (Guizhou; Zhou et al., 1984)

Calymenesun tingi — photo 3 — Photo 3 · palaeontologist Cranidium, pygidium and hypostome specimens Lectotype NIGP 3455 (Guizhou; Lu Yanhao 1975) (Guizhou; Zhou et al., 1984) (Guizhou; Zhou et al., 1984)

Classification

Order Phacopida / Suborder Calymenina / Superfamily Calymenoidea / Family Calymenidae

Genus

Calymenesun Kobayashi, 1951

Genus author

Kobayashi T.

Genus etymology

Calymene, a trilobite genus name; Sun, a surname, in honour of Prof. Sun Yunchu, the renowned Chinese

Species

C. tingi (Sun, 1931)

Species author

Sun Yunchu

Species etymology

Ting, a surname, in honour of Mr. Ding Wenjiang (Ting V. K.), one of the founders of geology in China, who collected the specimens

Age

Darriwilian to Sandbian (Middle to Late Ordovician)

Distribution

Guizhou

Synonyms

Calymene tingi; Calymene (Calymenesun) tingi

Diagnosis

Dorsal shield long-ovate, external mould with fine granules, internal mould smooth. Cranidium triangular; glabella bell-shaped, strongly convex with truncate front, abruptly inflated posteriorly, 3 pairs of glabellar furrows, L1 subtriangular; dorsal furrows wide and deep; anterior border tapering sharply forward into an upturned anterior cranidial spine; gonatoparian facial sutures; palpebral lobes small, convex; librigenae triangular. Thorax of 13 segments; axis subequal in width to pleurae. Pygidium nearly as long as wide, with a median cincture; axis with 4 rings plus a terminal piece, narrowest at the cincture, expanding distally to reach the posterior margin.

Remarks

This species is the type species of the genus Calymenesun.