Agnostida

Tomagnostella exsculpta

Order Agnostida / Suborder Agnostina / Superfamily Agnostoidea / Family Ptychagnostidae

Cambrian, Miaolingian Drumian to GuzhangianHunan, Shandong; Sweden, India

Tomagnostella exsculpta — photo 1 — Photo 1 · Cephalon RM Ar 2007 lectotype (Sweden; Whittington et al., 1997) PMU37173 (Sweden; Weidner et al., (India; Peng et al., 2009) 2023) (Hunan; Peng Shanchi 2020) (Shandong; Yuan Jinliang et al. 2012)

Tomagnostella exsculpta — photo 2 — Photo 2 · Cephalon RM Ar 2007 lectotype (Sweden; Whittington et al., 1997) PMU37173 (Sweden; Weidner et al., (India; Peng et al., 2009) 2023) (Hunan; Peng Shanchi 2020) (Shandong; Yuan Jinliang et al. 2012)

Tomagnostella exsculpta — photo 3 — Photo 3 · Cephalon RM Ar 2007 lectotype (Sweden; Whittington et al., 1997) PMU37173 (Sweden; Weidner et al., (India; Peng et al., 2009) 2023) (Hunan; Peng Shanchi 2020) (Shandong; Yuan Jinliang et al. 2012)

Tomagnostella exsculpta — photo 4 — Photo 4 · Cephalon RM Ar 2007 lectotype (Sweden; Whittington et al., 1997) PMU37173 (Sweden; Weidner et al., (India; Peng et al., 2009) 2023) (Hunan; Peng Shanchi 2020) (Shandong; Yuan Jinliang et al. 2012)

Tomagnostella exsculpta — photo 5 — Photo 5 · Cephalon RM Ar 2007 lectotype (Sweden; Whittington et al., 1997) PMU37173 (Sweden; Weidner et al., (India; Peng et al., 2009) 2023) (Hunan; Peng Shanchi 2020) (Shandong; Yuan Jinliang et al. 2012)

Classification

Order Agnostida / Suborder Agnostina / Superfamily Agnostoidea / Family Ptychagnostidae

Genus

Tomagnostella Kobayashi, 1939

Genus author

Kobayashi T.

Genus etymology

Tomagnostus, a trilobite genus name; -ella, diminutive suffix.

Species

T. exsculpta (Angelin, 1851)

Species author

Angelin N. P.

Species etymology

exsculpta, Latin, engraved in intaglio.

Age

Cambrian, Miaolingian Drumian to Guzhangian

Distribution

Hunan, Shandong; Sweden, India

Synonyms

Agnostus exsculptus; A. parvifrons var. nepos; Ptychagnostus exsculptus; Hypagnostus exsculptus; H. parvifrons nepos H. nepos; H. exsculptus geminus; H. hunanicus; H. quadratus; H. melicus; Tomagnostella nepos

Diagnosis

Cephalon and pygidium nearly round. Glabella convex, tapering forward at the anterior third, without frontal lobe; cheek with radiating furrows or none; basal lobe small. Pygidial axis long, terminal end close to the posterior border furrow; M2 pentagonal; a postaxial median furrow behind the pygidial axis; no posterolateral marginal spines.

Remarks

This species is the type species of Tomagnostella. Typical body length about 0.2-1 cm.