Agnostida

Tomagnostella sulcifera

Order Agnostida / Suborder Agnostina / Superfamily Agnostoidea / Family Ptychagnostidae

Cambrian, Miaolingian, GuzhangianHunan, Zhejiang; Sweden, Siberia

Tomagnostella sulcifera — photo 1 — Photo 1 · Pygidium SGU 4807 Topotype (Sweden; Whittington et al., 1997) (Sweden; Weidner et al., 2023) (Siberia; Pegel, 2000) (Hunan; Peng Shanchi 2020) (Zhejiang; Lu Yanhao et al. 1989)

Tomagnostella sulcifera — photo 2 — Photo 2 · Pygidium SGU 4807 Topotype (Sweden; Whittington et al., 1997) (Sweden; Weidner et al., 2023) (Siberia; Pegel, 2000) (Hunan; Peng Shanchi 2020) (Zhejiang; Lu Yanhao et al. 1989)

Tomagnostella sulcifera — photo 3 — Photo 3 · Pygidium SGU 4807 Topotype (Sweden; Whittington et al., 1997) (Sweden; Weidner et al., 2023) (Siberia; Pegel, 2000) (Hunan; Peng Shanchi 2020) (Zhejiang; Lu Yanhao et al. 1989)

Tomagnostella sulcifera — photo 4 — Photo 4 · Pygidium SGU 4807 Topotype (Sweden; Whittington et al., 1997) (Sweden; Weidner et al., 2023) (Siberia; Pegel, 2000) (Hunan; Peng Shanchi 2020) (Zhejiang; Lu Yanhao et al. 1989)

Tomagnostella sulcifera — photo 5 — Photo 5 · Pygidium SGU 4807 Topotype (Sweden; Whittington et al., 1997) (Sweden; Weidner et al., 2023) (Siberia; Pegel, 2000) (Hunan; Peng Shanchi 2020) (Zhejiang; Lu Yanhao et al. 1989)

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. sulcifera (Wallerius, 1895)

Species author

Wallerius I. D.

Species etymology

sulc-, furrow, groove; -fera, bearing.

Age

Cambrian, Miaolingian, Guzhangian

Distribution

Hunan, Zhejiang; Sweden, Siberia

Synonyms

Agnostus exsxulptus forma sulcifera; Agnostus exsxulptus didymus; Hypagnostus exsculptus didymus; Tomagnostella integra; Hypagnostus sulcifer; H. sulcifer integer; Tomagnostella tianmashanesis

Diagnosis

Cephalon similar to that of the type species Tomagnostella exsculpta, the main difference being the more slender pygidial axis with the terminal end far from the posterior border furrow. Specimens with intermediate characters also occur. , and the two may have an evolutionary relationship.

Remarks

Typical body length about 0.2-1 cm.