Stromboidea
Original comment of Fischer et al:
- Parnes described this species from incomplete specimens of the Bajocian in the Sinai Peninsula. The three Saudi Arabian specimens, although without labrum and smaller in size, seem to be follow Parnes' definition. Their proportions, the cyrtoconoid shape of the spire, and the bulges on their whorls are the same. In addition, they have exactly the same ornamentation. This consists of two to four spiral cords intercalated between the suture and the upper digital keel, three main threads with intercalated threads between the two keels of the last whorl, and about 10 main spiral threads doubled by intercalated threads below the lower digital keel. A spiny nodosity is found slightly before the middle part of the last whorl, on the upper digital keel, and the columellar edge shows a smooth and excavated callosity that is clearly limited on the outside.
Dicroloma triseriatum Parnes, 1981; Bajocian, middle Jurassic; Shaqra, Saudi Arabia; 32 mm; Coll. MNHN no. B74223; Copyright Museum national d'Histoire naturelle Paris
References:
- Fischer et al, 2001
- A. Parnes (1981) - Biostratigraphy of the Mahmal Formation (Middle and Late Bajocian) in Makhtesh Ramon (Negev, Southern Israel). Geological Survey of Israel, Jerusalem, no. 74, p. 1-55.
- Picard, L. & Hirsch, F. (1987) : The Jurassic stratigraphy in Israel and the adjacent countries. -The Israel Acad. Sci. and Humanities, 106 p.; Jerusalem.
