Asaphida

Tsaidamaspis diarmatus

Order Asaphida / Superfamily Asaphoidea / Family Asaphidae

Floian (Early Ordovician)Qinghai
Tsaidamaspis diarmatus — photo 1
Photo 1 · Restoration (Wei et al., 2023) Holotype NIGP 10115 (Qinghai; Zhang Wentang et al. 1960) Literature specimen (Qinghai; Wei et al., 2023)
Tsaidamaspis diarmatus — photo 2
Photo 2 · Restoration (Wei et al., 2023) Holotype NIGP 10115 (Qinghai; Zhang Wentang et al. 1960) Literature specimen (Qinghai; Wei et al., 2023)
Tsaidamaspis diarmatus — photo 3
Photo 3 · Restoration (Wei et al., 2023) Holotype NIGP 10115 (Qinghai; Zhang Wentang et al. 1960) Literature specimen (Qinghai; Wei et al., 2023)
Classification
Order Asaphida / Superfamily Asaphoidea / Family Asaphidae
Genus
Tsaidamaspis Chang & Fan, 1960
Genus author
Zhang Wentang, Fan Jiasong
Genus etymology
Tsaidam, Qaidam, Qinghai
Species
Tsaidamaspis diarmatus Chang & Fan, 1960
Species author
Zhang Wentang, Fan Jiasong
Species etymology
di-, double; armatus, armed, equipped
Age
Floian (Early Ordovician)
Distribution
Qinghai
Synonyms
Plesiomegalaspis (Tsaidamaspis) diarmatus; Megalaspidella (Tsaidamaspis) diarmatus
Diagnosis
Cranidium gently convex; anterior border flat; glabella long, constricted medially, preglabellar furrow deep laterally and shallow medially, anterior glabellar lobe with a V-shaped median furrow, a median node near the occipital furrow at the posterior part of the glabella, with 5 pairs of shallow glabellar furrows; dorsal furrows deep; palpebral lobes small, semicircular; anterior branches of facial sutures widening forward then smoothly curving inward, meeting at an obtuse angle; librigenae wide with short genal spines of wide base. Pygidium triangular, surface with irregular terrace lines; axis narrow and long, conical, with at least 20 rings; pleural region with at least 14 pleural furrows and triangular articulating facets; border wide, bearing two broad marginal spines medially.
Remarks
This species is the type species of the genus Tsaidamaspis.