Agnostida

Clavagnostus calensis

Order Agnostida / Suborder Agnostina / Superfamily Agnostoidea / Family Clavagnostidae

Cambrian, Miaolingian, GuzhangianHunan, Zhejiang; Argentina

Clavagnostus calensis — photo 1 — Photo 1 · Holotype MCNAM 7592 (Argentina; Tortello et al., 1997) Illustrated specimens (Argentina; Tortello 2017) Illustrated specimens (Hunan; Peng (Zhejiang; Baishui) Shanchi 2020)

Clavagnostus calensis — photo 2 — Photo 2 · Holotype MCNAM 7592 (Argentina; Tortello et al., 1997) Illustrated specimens (Argentina; Tortello 2017) Illustrated specimens (Hunan; Peng (Zhejiang; Baishui) Shanchi 2020)

Clavagnostus calensis — photo 3 — Photo 3 · Holotype MCNAM 7592 (Argentina; Tortello et al., 1997) Illustrated specimens (Argentina; Tortello 2017) Illustrated specimens (Hunan; Peng (Zhejiang; Baishui) Shanchi 2020)

Clavagnostus calensis — photo 4 — Photo 4 · Holotype MCNAM 7592 (Argentina; Tortello et al., 1997) Illustrated specimens (Argentina; Tortello 2017) Illustrated specimens (Hunan; Peng (Zhejiang; Baishui) Shanchi 2020)

Classification

Order Agnostida / Suborder Agnostina / Superfamily Agnostoidea / Family Clavagnostidae

Genus

Clavagnostus Howell, 1937

Genus author

Howell B. F.

Genus etymology

clav-, Latin, club; Agnostus, a trilobite genus name.

Species

C. calensis Rusconi, 1950

Species author

Rusconi C.

Species etymology

Unknown.

Age

Cambrian, Miaolingian, Guzhangian

Distribution

Hunan, Zhejiang; Argentina

Synonyms

Tomagnostus?Canotensis; Clavagnostus?rawlingi; Clavagnostus(Leptagnostus)lanceolatus; C.(L.)rarus Clavagnostus canotensis

Diagnosis

Cephalon subsquare, border narrow, border furrow narrow and shallow, with a pair of broad-based posterolateral spines; outer part of pleural region with radiating furrows, inner part with short furrows arranged around the glabella; glabella short, Anterior end sharply pointed, posterior end bluntly pointed; Glabellar furrows effaced; Basal lobe short and small, wide triangular; Preglabellar median furrow deep and complete. Border and border furrow of pygidium narrow, axial area of border pointed; inner lobe with furrows similar to those of the cephalic inner lobe; pygidial axis strongly constricted inward at M2; median node very long, crossing the entire M1 and M2 and extending to the anterior third of the posterior axial ring; terminal end of posterior axial ring pointed, with a pair of long pits at the posterior third; pygidial posterolateral spines long.