Asaphida

Hysterolenus asiaticus

Order Asaphida / Superfamily Asaphoidea / Family Ceratopygidae

Stage 10 (Furongian, Cambrian) to Tremadocian (Early Ordovician)Zhejiang, Hunan

Hysterolenus asiaticus — photo 1 — Photo 1 · Holotype NIGP23925 (Zhejiang; Peng 2020) Literature specimen (Zhejiang; Lu Yanhao et al. 1980) Meraspid specimen (Hunan; Y.W) Complete dorsal exoskeleton Complete dorsal exoskeleton, 6 cm long (Hunan; Baishui) (Hunan; Guodong)

Hysterolenus asiaticus — photo 2 — Photo 2 · Holotype NIGP23925 (Zhejiang; Peng 2020) Literature specimen (Zhejiang; Lu Yanhao et al. 1980) Meraspid specimen (Hunan; Y.W) Complete dorsal exoskeleton Complete dorsal exoskeleton, 6 cm long (Hunan; Baishui) (Hunan; Guodong)

Hysterolenus asiaticus — photo 3 — Photo 3 · Holotype NIGP23925 (Zhejiang; Peng 2020) Literature specimen (Zhejiang; Lu Yanhao et al. 1980) Meraspid specimen (Hunan; Y.W) Complete dorsal exoskeleton Complete dorsal exoskeleton, 6 cm long (Hunan; Baishui) (Hunan; Guodong)

Hysterolenus asiaticus — photo 4 — Photo 4 · Holotype NIGP23925 (Zhejiang; Peng 2020) Literature specimen (Zhejiang; Lu Yanhao et al. 1980) Meraspid specimen (Hunan; Y.W) Complete dorsal exoskeleton Complete dorsal exoskeleton, 6 cm long (Hunan; Baishui) (Hunan; Guodong)

Hysterolenus asiaticus — photo 5 — Photo 5 · Holotype NIGP23925 (Zhejiang; Peng 2020) Literature specimen (Zhejiang; Lu Yanhao et al. 1980) Meraspid specimen (Hunan; Y.W) Complete dorsal exoskeleton Complete dorsal exoskeleton, 6 cm long (Hunan; Baishui) (Hunan; Guodong)

Classification

Order Asaphida / Superfamily Asaphoidea / Family Ceratopygidae

Genus

Hysterolenus Moberg, 1898

Genus author

Moberg J. C.

Genus etymology

Hystero-, Greek, after, behind; Olenus, a trilobite genus name

Species

H. asiaticus Lu, 1959

Species author

Lu Yanhao

Species etymology

Asia

Age

Stage 10 (Furongian, Cambrian) to Tremadocian (Early Ordovician)

Distribution

Zhejiang, Hunan

Diagnosis

Glabella subcylindrical with rounded front and four pairs of deeply impressed glabellar furrows; preglabellar field long and flat; anterior border narrow, ridge-like; palpebral lobes small, at the middle of the cranidium, close to the glabella; librigenae extremely wide with long genal spines. Thorax of 6 segments; axis narrow; pleural furrows distinct, pleural spines short and pointed. Pygidium semicircular to rounded-triangular; axis narrow, with 7 axial rings and a terminal piece; postaxial ridge reaching the border; pleural and interpleural furrows distinct; second pleural ring extended backward into a slender long pleural spine.