Acontheus Angelin, 1851

Unger, Tanja, Hildenbrand, Anne, Stinnesbeck, Wolfgang & Austermann, Gregor, 2022, Biostratigraphy and taxonomy of polymerid trilobites of the Manuels River Formation (Drumian, middle Cambrian), Newfoundland, Canada, Geodiversitas 44 (33), pp. 1051-1087 : 1075-1076

Genus Acontheus Angelin, 1851

Acontheus Angelin, 1851: 5 . —

Type species: Acontheus acutangulus Angelin, 1851 , by original designation.

Aneucanthus – Angelin 1851: X.

Aneuacanthus – Barrande 1857: 17.

DIAGNOSIS. — Cranidium with narrow margin; glabella expands anteriorly, extends to anterior margin; pygidium subelliptical; pygidial axis of three or four axial rings, not reaching pygidial margin; wide pleural furrows extend to border with marked posterior deflection (based on Angelin 1851; Jago et al. 2012, with modifications).

REMARKS

Angelin (1851) first described the genus Acontheus and renamed it in the same publication. He introduced the name Aneucanthus for the genus, but as this was preoccupied by the name of a snake, he renamed the trilobite Aconthias. Barrande (1857) used Aneuacanthus for the genus, which was also used by Lindström in the second edition of Angelin’s (1851) work that was revised and published asAngelin (1878). We suggest that Aneuacanthus was incorrectly spelled as Barrande (1857) used the name without any further discussion or explanation. According to Westergård (1950: 8) Acontheus can be distinguished from Aconthias and therefore the original name Acontheus is used herein.