Stroborineceras, Korn & Bockwinkel, 2022

Korn, Dieter & Bockwinkel, Jürgen, 2022, Early Carboniferous nautiloids from the Central Sahara, southern Algeria, European Journal of Taxonomy 831, pp. 67-108 : 75

Genus Stroborineceras gen. nov.

urn:lsid:zoobank.org:act:AA852A1D-1B99-4B73-A82E-24CC0BADB162

Type species

Stroborineceras insalahensis gen. et sp. nov.

Diagnosis

Genus of the family Trigonoceratidae with evolute conch; whorls not embracing; whorl profile depressed and rounded-triangular (escutcheon-shaped) with flattened or weakly concave venter and pronounced ventrolateral shoulders. Ornament with some spiral ridges on the flank, sometimes also on the margin of the venter. Suture line with broad, shallow external lobe and narrowly rounded ventrolateral saddle. Siphuncle small with subcentral position slightly shifted towards the venter.

Etymology

A combination of the two genus names Stroboceras and Rineceras , because of the presence of characters of both genera in the new genus.

Included species

Stroborineceras insalahensis gen. et sp. nov., Algeria; Stroborineceras felis gen. et sp. nov., Algeria; and questionably Nautilus (Trematodiscus) Meekianus Winchell, 1862 , Michigan and Nautilus (Trematodiscus) strigatus Winchell, 1862 , Michigan.

Remarks

Stroborineceras gen. nov. combines the morphological features of the apparently ancestral genus Rineceras (simple whorl profile and spiral lines on the flank) and descendant genera such as Stroboceras or Vestinautilus (pronounced ventrolateral shoulder with sharp longitudinal ridges and submarginal ventral grooves).

Stroborineceras gen. nov. differs from Rineceras in the more pronounced ventrolateral shoulder, which is reinforced by some raised longitudinal ridges, whereas in Rineceras it is rounded. In addition, the submarginal ventral longitudinal groove, which in Rineceras is only present on the juvenile stage, is still distinct in Stroborineceras gen. nov. in the middle growth stage.

Stroborineceras gen. nov. differs from Stroboceras and Vestinautilus in the absence of the strong longitudinal ridges and broad longitudinal grooves that cause a polygonal whorl profile in these two genera. Instead, Stroborineceras gen. nov. merely has spiral lines on the flanks.