Sinuarbullina Grundel 1997

Genus Sinuarbullina Grundel, 1997

Type species. Sinuarbullina ansorgi Grundel, 1997; Jurassic, Bathonian, NE Germany, NW Poland.

Diagnosis. The generic diagnosis follows Grundel & Nutzel (2012). The shell is fusiform with a distinctly elevated spire. The teleoconch whorls have a subsutural ramp. The transition from the ramp to the outer whorl face is either rounded or angular, sometimes demarcated abapically by a spiral concavity. Whorls are smooth in most species, although faint spiral furrows occur on the base in a few of them. Growth lines are prosocyrt on the outer whorl face but strongly curving in an abapertural direction and opisthocyrt at the ramp. The aperture is relatively low for the group, teardrop-shaped and lacks a columnellar fold. The protoconch is trans- to medioaxial.

Remarks. Pan et al. (2003) described Jiangxispira as a new genus using the following diagnostic features: (1) a small, high-spired, slender, fusiform shell; (2) teleoconch whorls with narrow shoulder; and (3) a heterostrophic, Silicified Early Triassic marine assemblage from Svalbard 869 discoidal, transaxial protoconch. These characters are all within the diagnostic features of the genus Sinuarbullina Grundel (1997), and Jiangxispira is, therefore, a junior synonym of Sinuarbullina.