Cirsotrema loerentheyi ( Boettger, 1902 )

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 : 45

Cirsotrema loerentheyi ( Boettger, 1902)

Figs 17B

* Scalaria (Cirsotrema) Loerentheyi n. sp. — Boettger 1902: 85.

Scalaria (Cirsotrema) Loerentheyi Boettger— Boettger 1906: 92 .

Cirsotrema Loerentheyi Boettger— Cossmann 1912: 183 , pl. 5, fig. 12.

Scala (Cirsotrema) loerentheyi (Boettger) — Zilch 1934: 230, pl. 10, fig. 77.

Type material. Lectotype (designated by Zilch 1934: 230), SMF 380166_12-1447 ( XII 1447 a), SL: 9.5 mm, MD: 4.5 mm, CoŞteiu de Sus ( Romania), illustrated in Zilch (1934: pl. 10, fig. 77), Figs 17B .

Revised description. Shell small, robust, moderately broad (apical angle ~29°), gradate, faintly coronate. Protoconch and first teleoconch whorls unknown. Early teleoconch whorls convex with convex subsutural ramp, strongly raised laminae and three prominent spiral cords in axial interspaces. Later teleoconch whorls with broad, shallow, weakly concave subsutural ramp and weakly angled shoulder, subcylindrical below, with periphery placed mid-whorl. Suture moderately impressed, fenestrate. Sculpture of moderately close-set, prominent, strongly raised, weakly prosocline, frondose lamellae separated by wider interspaces, partly aligned axially and partly fused to lamellae on preceding whorl (~14: ~16: 20). Lamellae weakly coronate along shoulder of last two whorls. Axial interspaces with three low, broad spiral cords below shoulder. Last whorl attaining ~45% of total height, with sharp basal angulation delimited by prominent, slightly beaded peribasal cord, basal disc slightly concave, lamellae only slightly weaker on base. Fasciole short, broad, with very prominent growth lines. Aperture circular. Columella concave. Outer lip strongly thickened by varix. Columellar callus forming narrow rim, detached from base, parietal callus delicate. Peristome duplex. Umbilicus reduced to narrow chink.

Discussion. Cirsotrema loerentheyi ( Boettger, 1902) is characterized by its cancellate sculpture of frondose lamellae and low, broad spiral cords. Cirsotrema miovaricosum ( Sacco, 1891) , from the Tortonian of Stazzano ( Italy), has comparable sculpture but differs in its broader and orthocline varices and the greater number of narrower spiral cords (see Ferrero Mortara et al. 1984: pl. 5, fig. 16). Cirsotrema couffoni de Boury in Cossmann, 1912, from the Tortonian of the Loire Basin ( France), might represent a closely related species that differs mainly in the slenderer shape and steeper subsutural ramp (see Cossmann 1912: pl. 5, fig. 11). Cirsotrema duciei ( Wright, 1855) , from the Langhian of Malta, has comparable sculpture but is slenderer, has a weaker shoulder and has more numerous, less frondose lamellae (see Wright 1855: pl. 7, fig. 3; Cilia 2024: pl. 3, figs J–M).

Paleoenvironment. Unknown.

Distribution in Central Paratethys. Badenian (Middle Miocene): Făget Basin: CoŞteiu de Sus ( Romania) ( Boettger 1906).

Figures

FIGURE 17. A1–A2. Clathrus corrugatus sp. nov., holotype, NHMW 2000z0092/0008, Karnabrunn (Austria). B. Cirsotrema loerentheyi (Boettger, 1902), lectotype, SMF 380166_12-1447 (XII 1447a), CoŞteiu de Sus (Romania). C1–C2. Cirsotrema kokayi Kovács, Leél-Őssy & Vicián, 2023, holotype, PAL 2022.54.1, Parádfürdö, Ilona Valley (Hungary). D1–D3. Cirsotrema menkveldaePfister &Wegmüller,2007, holotype, NMBE Nr.B7648, Hohburggraben,Belpberg (Switzerland).E1–E3. Cirsotrema menkveldae Pfister & Wegmüller, 2007, paratype, NMBE Nr. B7649, Hohburggraben, Belpberg (Switzerland).