Eucycloidea bitneri Nakrem 2017, sp. nov. ...
Eucycloidea bitneri sp. nov. (Fig. 4) 2011 Eucyclus sp.; Hammer et al. 2011, fig. 7l, 2015 Ambercyclus sp.; Hryniewicz et al. 2015a, table 1. Diagnosis. Shell trochiform, with strong, nodose medial keel, nodes merge later into band. Flank ornamented by dense network of tiny axial and spiral riblets....
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Zenodo
2017
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Online Access: | https://dx.doi.org/10.5281/zenodo.6009559 https://zenodo.org/doi/10.5281/zenodo.6009559 |
Summary: | Eucycloidea bitneri sp. nov. (Fig. 4) 2011 Eucyclus sp.; Hammer et al. 2011, fig. 7l, 2015 Ambercyclus sp.; Hryniewicz et al. 2015a, table 1. Diagnosis. Shell trochiform, with strong, nodose medial keel, nodes merge later into band. Flank ornamented by dense network of tiny axial and spiral riblets. Base with strong spiral ribs. Holotype: PMO 217.235, H = 46 mm, W = 33 mm. Type locality and age: Seep #3, Sassenfjorden, Svalbard; late Tithonian, Late Jurassic. Other material: Fourteen specimens from seep #3, three specimens from seep #9, and two specimens from seep #13 (Table 1). Description. Protoconch unknown. Shell trochiform with strong medial keel. Additional keels are present just at the adapical and abapical suture. The lateral flank is covered by numerous fine axial riblets. Above the medial keel, the riblets are strongly opisthocyrt while below the medial keel only weakly opisthocyrt. The medial keel is covered by a series of blunt, smooth and wide nodes, the other keels are intersected by axial ... : Published as part of Nakrem, Hans Arne, 2017, Gastropods from the Late Jurassic - Early Cretaceous seep deposits in Spitsbergen, Svalbard, pp. 351-374 in Zootaxa 4329 (4) on pages 356-357, DOI: 10.11646/zootaxa.4329.4.3, http://zenodo.org/record/1003014 ... |
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