Stromboidea
Description of Alaria unispinosa by Moore, 1867, p. 197:
- " Shell fusiform, elongate, turreted ; apex acute; volutions 8, angulated and carinated ; surface witn numerous transverse striae, and with longitudinal costae on the upper whorls. From the carina on the body whorl there springs a very fine and narrow spine, which curves upwards and extends more than the diameter of the shell beyond the margin; outer lip slightly recurved; aperture rather large, lengthened, and continued into a very long slender canal; columbella very extended and slightly folded. This elegant shell is rather plentiful in the leptaena clays of zone A d of the Upper Lias, at Ilminster and other localities, and hitherto we have failed to recognize it elsewhere. It is only found in the laminae of the clay in which it is compressed and has in all cases lost its test."
Locus typicus: Ilminster, Somerset County, South West Region, England
Stratum typicum: Leptaena Clay, Pliensbachian, lower Jurassic
Alaria unispinosa Moore, 1867, pl. 4, fig. 1, 2
References
- W. H. Hudleston and E. Wilson (1892)
- Moore, C. 1867. On the Middle and Upper Lias of the southwest of England. Proceedings of the Somersetshire Archaeological and Natural History Society, 13 , 119—244. Link
- Thomas Wright, 2015. A Monograph on the Lias Ammonites of the British Islands, Vol. 1, Cambridge University Press, pp. 454.
Internet
