Asaphida

Megistaspidella triangularis

Order Asaphida / Superfamily Asaphoidea / Family Asaphidae

Dapingian (Middle Ordovician)?Russia

Megistaspidella triangularis — photo 1 — Photo 1 · Type specimen? (Russia; Klikushin et al., 2009) Dorsal and ventral views of a complete dorsal exoskeleton (Russia; Baiya) Complete dorsal exoskeleton Complete dorsal exoskeleton (Russia; Yicheng) (Russia; Baiya)

Megistaspidella triangularis — photo 2 — Photo 2 · Type specimen? (Russia; Klikushin et al., 2009) Dorsal and ventral views of a complete dorsal exoskeleton (Russia; Baiya) Complete dorsal exoskeleton Complete dorsal exoskeleton (Russia; Yicheng) (Russia; Baiya)

Megistaspidella triangularis — photo 3 — Photo 3 · Type specimen? (Russia; Klikushin et al., 2009) Dorsal and ventral views of a complete dorsal exoskeleton (Russia; Baiya) Complete dorsal exoskeleton Complete dorsal exoskeleton (Russia; Yicheng) (Russia; Baiya)

Megistaspidella triangularis — photo 4 — Photo 4 · Type specimen? (Russia; Klikushin et al., 2009) Dorsal and ventral views of a complete dorsal exoskeleton (Russia; Baiya) Complete dorsal exoskeleton Complete dorsal exoskeleton (Russia; Yicheng) (Russia; Baiya)

Megistaspidella triangularis — photo 5 — Photo 5 · Type specimen? (Russia; Klikushin et al., 2009) Dorsal and ventral views of a complete dorsal exoskeleton (Russia; Baiya) Complete dorsal exoskeleton Complete dorsal exoskeleton (Russia; Yicheng) (Russia; Baiya)

Classification

Order Asaphida / Superfamily Asaphoidea / Family Asaphidae

Genus

Megistaspidella Jaanusson, 1956

Genus author

Jaanusson V.

Genus etymology

Megistaspis, a trilobite genus name; -ella, a diminutive suffix

Species

M. triangularis (Schmidt, 1906)

Species author

Schmidt F.

Species etymology

triangularis, Latin, triangular

Age

Dapingian (Middle Ordovician)?

Distribution

Russia

Synonyms

Megalaspis acuticauda triangularis

Diagnosis

Cephalon triangular; glabella short, subrectangular, moderately convex, with a glabellar node; preglabellar field long; occipital furrow faint; eyes small and convex; fixigenae narrow in the palpebral area; librigenae narrow and long with genal spines slender and medium-length. Thorax of 8 segments; axis narrower than pleurae; pleural furrows wide, pleural spines absent. Pygidium triangular; border with a short pointed spine medially.

Remarks

Commonly known as the "triangular shield".