Laxispira, Gabb, 1877

Hansen, Thomas, 2019, Gastropods from the Cretaceous-Palaeogene boundary in Denmark, Zootaxa 4654 (1), pp. 1-196 : 110-111

Laxispira sp.

Fig. 27O

Material. MGUH 33193, an external mould in the unformally catalogued sample SH.3.B–C, and a last mould without number in the old collections at the Natural History Museum of Denmark.

Occurrence. Lithified top of the Maastrichtian Tor Formation at Højerup Church and Holtug Quarry, Stevns.

Description. Protoconch not known. Teleoconch loosely coiled with round aperture and apparently without keel. Shell sculpture of well defined, densely spaced granular spiral ribs crossed by densely spaced growth lines. Spiral ribs may become slightly coarser on abapical side of whorl.

Measurements. Largest specimen with aperture diameter of 11.3 mm.

Remarks. The taxon has a strong resemblance to the Maastrichtian L. libycus Quaas, 1902 from Egypt and the Late Maastrichtian L. pinguis Holzapfel and L. cochleiformis (Müller) from Holland as figured by Wenz (1939), but differs by its strongly and evenly beaded spiral ribs. It also resembles Laxispira monilifera Sohl, 1964b from the Late Cretaceous of Mississippi, but differs by a more evenly beaded spiral sculpture.

Figures

FIGURE 27. A–B. Melanella? sp., Silicone cast of MGUH 33183. Width 1.4 mm. C–E. Vermetus sp., C. Silicone cast of attached tube MGUH 33184. Largest diameter 6.6 mm. D. Inner mould of protoconch and initial teleoconch inside bryozoan ball. MGUH 33185. Protoconch 0.5 mm wide. E. Silicone cast of MGUH 33186. Width 3.5 mm. F–J. Thylacodes contendis n. sp. F. Attached holotype mould MGUH 33187. Width 2.4 mm. G–H. Silicone cast of paratype MGUH 33188. Width 2.9 mm. I. Silicone cast of paratype MGUH 33189. Width 3.0 mm. J. Silicone cast of free whorl paratype MGUH 33190. Tube diameter 1.8 mm. K–M. Thylacodes? sp., Silicone cast of MGUH 33191. Width 2.4 mm. N. Dendropoma sp., Protoconch and initial teleoconch tube of MGUH 33192. Width 1.7 mm. O. Laxispira sp., Silicone cast of MGUH 33193. Width 3.6 mm. P–R. Epetrium s.l. skeldervigensis n. sp. P. Silicone cast of holotype MGUH 33194. Width 2.4 mm. Q. Silicone cast of paratype MGUH 33195. Width 4.0 mm. R. Silicone cast of paratype MGUH 33196. Width 3.6 mm. S. Triphoridae genus et sp. indet. Sinistrally coiled protoconch MGUH 33197. Width 0.7 mm. T–W. Cerithiopsis restemlongis n. sp. T. Silicone cast of holotype MGUH 33198. Width 1.0 mm. U. Silicone cast of paratype MGUH 33199. Width 1.5 mm. V. Silicone cast of paratype protoconch MGUH 33200. Width 0.5 mm. W. Silicone cast of paratype protoconch MGUH 33201. Width 0.6 mm and height 1.1 mm. X. Cerithiopsis? sp., Silicone cast of MGUH 33202. Width 0.6 mm. Y–AE. Thereitis carlsbergi n. sp. Y–Z. Silicone cast of holotype specimen MGUH 33203. Width of protoconch 0.6 mm and teleoconch 1.4 mm. AE. Silicone cast of paratype MGUH 33204. Width 0.7 mm.