Cylindriscala acus ( Watson, 1883 )

Harzhauser, Mathias & Landau, Bernard M., 2025, The Epitoniidae (Gastropoda, Epitonioidea) of the Miocene Central Paratethys Sea-an overwhelming diversity, Zootaxa 5630 (1), pp. 1-142 : 56-57

publication ID	https://doi.org/10.11646/zootaxa.5630.1.1
publication LSID	lsid:zoobank.org:pub:89462472-D932-4255-880F-C6EF15220A31
persistent identifier	https://treatment.plazi.org/id/03D787A4-FFD2-FFDC-FF3F-F957FA879245
treatment provided by	Plazi
scientific name	Cylindriscala acus ( Watson, 1883 )
status

Treatment

Cylindriscala acus ( Watson, 1883) View in CoL

Figs 20F View FIGURE 20 1 –F View FIGURE 1 2 View FIGURE 2 , 21E View FIGURE 21

* Scalaria acus View in CoL n. sp. — Watson 1883: 608, pl. 9, fig. 2.

Scala fulgens de Boury View in CoL sp. nov. —de Boury 1909b: 463.

Cylindriscala acus ( Watson, 1883) View in CoL — Bouchet & Warén 1986: 531, figs 1117, 1128, 1229, 1236.

Cylindriscala acus ( Watson, 1883) View in CoL — Weil et al. 1999: 34, fig. 82.

Type material. Holotype, BMNH 1887.2 .9.498 (Natural History Museum London), West of Azores, https://data. nhm.ac.uk/dataset/collection-specimens/resource/05ff2255-c38a-40c9-b657-4ccb55ab2feb/record/3499770

Illustrated material. NHMWW 1866 /0001/0717a, SL: 3.3 mm , MD: 1.3 mm, Möllersdorf ( Austria), Figs 20F View FIGURE 20 1 –F View FIGURE 1 2 View FIGURE 2 , 21E View FIGURE 21

Description (of Paratethyan material). Very small shell, moderately slender, turreted (apical angle ~20°). Protoconch and first teleoconch whorls unknown from Paratethyan material. High conical of 2.5 weakly convex whorls in extant specimens. with prominent spiral cords at apical suture and delicate axial ribs on last whorl (see Bouchet & Warén 1986; fig. 1229). Early teleoconch of strongly and evenly convex whorls with poorly delimited, narrow subsutural ramp, periphery placed mid-whorl. Later whorls with convex to vaguely subcylindrical periphery. Suture deeply impressed. Sculpture of moderately close-set, very prominent, convex, orthocline axial ribs, separated by narrower interspaces, not aligned axially (14: 13: 11). Axial ribs most prominent along periphery, rapidly weakening on subsutural ramp. Interspaces glossy, smooth. Last whorl attaining ~30% of total height, basal angulation delimited by very prominent peribasal cord, axial ribs terminate at peribasal cord, base weakly concave, smooth. Aperture subcircular, columella weakly concave. Outer lip not preserved.

Discussion. This specimen is strikingly similar to the extant Cylindriscala acus ( Watson, 1883) . Watson (1883) mentioned 15 and 17 axial ribs for the penultimate and last whorls, which is more than seen in the Paratethyan shell, but at same growth stage the Paratethyan shell is indistinguishable from the extant specimens. Therefore, we tentatively treat both occurrences as conspecific despite the large stratigraphic gap of about 14.5 Ma. Cylindriscala rugata sp. nov. has a comparable shape but has fewer and broader axial ribs. Cylindriscala bellissima sp. nov. is much slenderer and has fewer but even more prominent axial ribs.

Paleoenvironment. The species lives in bathyal water depths ( Bouchet & Warén 1986). Similarly, Miocene occurrences in the Baden Formation of the Vienna Basin suggest middle to outer neritic settings in up to 250 m water depth ( Kranner et al. 2021).

Distribution in Central Paratethys. Badenian (Middle Miocene): Vienna Basin: Möllersdorf ( Austria) (hoc opus).

Northeastern Atlantic. Present-day: Portugal, the Canaries and the Azores ( Bouchet & Warén 1986).