Agnostida

Hypagnostus parvifrons

Order Agnostida / Suborder Agnostina / Superfamily Agnostoidea / Family Peronopsidae

Cambrian, Miaolingian, DrumianShandong; Europe, Australia, North America
Hypagnostus parvifrons — photo 1
Photo 1 · Cephalon holotype SGU 4769, pygidium SGU 4768 (Sweden; Whittington et al., Reconstruction Complete dorsal shield 1997) (drawn by Haixiang) (Shandong; Haixiang) Complete Complete dorsal shield dorsal shield (Shandong; Guodong) (Shandong; Baishui)
Hypagnostus parvifrons — photo 2
Photo 2 · Cephalon holotype SGU 4769, pygidium SGU 4768 (Sweden; Whittington et al., Reconstruction Complete dorsal shield 1997) (drawn by Haixiang) (Shandong; Haixiang) Complete Complete dorsal shield dorsal shield (Shandong; Guodong) (Shandong; Baishui)
Hypagnostus parvifrons — photo 3
Photo 3 · Cephalon holotype SGU 4769, pygidium SGU 4768 (Sweden; Whittington et al., Reconstruction Complete dorsal shield 1997) (drawn by Haixiang) (Shandong; Haixiang) Complete Complete dorsal shield dorsal shield (Shandong; Guodong) (Shandong; Baishui)
Hypagnostus parvifrons — photo 4
Photo 4 · Cephalon holotype SGU 4769, pygidium SGU 4768 (Sweden; Whittington et al., Reconstruction Complete dorsal shield 1997) (drawn by Haixiang) (Shandong; Haixiang) Complete Complete dorsal shield dorsal shield (Shandong; Guodong) (Shandong; Baishui)
Hypagnostus parvifrons — photo 5
Photo 5 · Cephalon holotype SGU 4769, pygidium SGU 4768 (Sweden; Whittington et al., Reconstruction Complete dorsal shield 1997) (drawn by Haixiang) (Shandong; Haixiang) Complete Complete dorsal shield dorsal shield (Shandong; Guodong) (Shandong; Baishui)
Hypagnostus parvifrons — photo 6
Photo 6 · Cephalon holotype SGU 4769, pygidium SGU 4768 (Sweden; Whittington et al., Reconstruction Complete dorsal shield 1997) (drawn by Haixiang) (Shandong; Haixiang) Complete Complete dorsal shield dorsal shield (Shandong; Guodong) (Shandong; Baishui)
Classification
Order Agnostida / Suborder Agnostina / Superfamily Agnostoidea / Family Peronopsidae
Genus
Hypagnostus Jaekel, 1909
Genus author
Jaekel O.
Genus etymology
hyp-, deficient, reduced, low, below; Agnostus, a trilobite genus name.
Species
H. parvifrons (Linnarsson, 1869)
Species author
Linnarsson J. G. O.
Species etymology
parvi-, small; frons, forehead, front.
Age
Cambrian, Miaolingian, Drumian
Distribution
Shandong; Europe, Australia, North America
Synonyms
Agnostus parvifrons; A. kushanensis; A. parvifrons var. latelimbatus; Hypagnostus parvifrons latelimbatus; Cotalagnostus kushanensis; H. clipeus; H. metisensis; H. andinus; H. latilimbata; H. subparallelus; H. Parvifrons parvifrons
Diagnosis
Dorsal surface smooth, cephalon and pygidium almost round. Glabellar frontal lobe absent, posterior segment convex; border furrow narrow and deep, border of moderate width. Pygidial axis long, tapering backward into a pointed arch, anterior axial node at the anterior third; border furrow narrow and deep, curving forward at the midline; border widest medially, forming a triangular area; no lateral spines.
Remarks
This species is the type species of Hypagnostus. Typical body length about 0.2-1 cm.