Librariscala costatissima, Harzhauser & Landau, 2025

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 : 88-90

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-FFB2-FFBE-FF3F-FB87FB8C9689
treatment provided by	Plazi
scientific name	Librariscala costatissima
status	sp. nov.

Treatment

Librariscala costatissima sp. nov.

Figs 4D View FIGURE 4 , 34E–F View FIGURE 34 , 35A View FIGURE 35

Epitonium cf. pulchellum (Bivona e Bernardi, 1832) View in CoL — Landau et al. 2013: 139, pl. 20, fig. 9.

Type material. Holotype, NHMW 1997 View Materials z0178/0972a, SL: 7.4 mm, MD: 3.3 mm, Bad Vöslau ( Austria), Figs 4D View FIGURE 4 , 34E View FIGURE 34 1 – E View FIGURE 1 2 View FIGURE 2 , 35A View FIGURE 35 . Paratype, NHMW 1874 View Materials /0058/1126, SL: 3.8 mm , MD: 1.8 mm, Seyithasan ( Turkey), illustrated in Landau et al. 2913: pl. 20, fig. 9), Figs 34F View FIGURE 34 1 –F View FIGURE 1 2 View FIGURE 2 .

Type locality. Bad Vöslau ( Austria), Vienna Basin .

Type stratum. Baden Formation.

Age. Middle Miocene, middle Badenian (Langhian).

Etymology. Superlative of costata (Latin for ribbed), revering to the high number of axial ribs.

Diagnosis. Small, moderately broad conical shell with turreted protoconch and moderately convex teleoconch whorls with many, close-set, broad, flat lamellae with narrow interspaces and three broad flattened varices per whorl.

Description. Shell small, moderately broad conical (apical angle ~30°). Protoconch turreted of 4.5 weakly convex, smooth whorls. Teleoconch of four whorls with steep, weakly concave subsutural ramp, moderately convex below, periphery distinctly below mid-whorl. Suture moderately impressed. Sculpture of numerous, densely spaced, broad, low, weakly prosocline, internally lamellose lamellae, not aligned axially, separated by narrower interspaces (19: ~33: ~38). Crests of lamellae strongly rolled over with indistinct pimples especially close to the adapical suture. Three varices per whorl more prominent, broad and flattened. Interspaces between varices smooth. Last whorl slightly allometrically widening, attaining 48% of total height, base convex, no peribasal cord, lamellae persisting over base, strongly rolled over. Fasciole short, broad, with distinct growth lines. Aperture ovate. Columella nearly straight. Columellar callus forming narrow rim attached to fasciole, parietal callus delicate. Peristome strongly thickened, duplex. Basal lip slightly widening. No umbilicus.

Discussion. Kilburn (1985) mentioned spiral threads in his diagnosis of Librariscala , which are not seen in the Paratethyan species. Therefore, our generic placement might be disputed. However, the peculiar sculpture (= “ tubular ” varices of Kilburn 1985) of Librariscala costatissima sp. nov. is characteristic for the genus. García (2016) described “ pimple-like projections ” on the varices of his Librariscala boutetorum from French Polynesia (see García, 2016: fig 1E). These delicate projections are also seen in Librariscala costatissima , which differs from Librariscala boutetorum in its conical outline and less convex whorls (see García 2016: fig. 1). Similarly, Librariscala parvonatrix ( Kilburn, 1985) , from South Africa, is distinguished by its more strongly convex whorls ( Kilburn 1985: figs 110–112, Weil et al. 1999: fig. 151).

This species was identified as Epitonium cf. pulchellum (Bivona e Bernardi, 1832) by Landau et al. (2013), who discussed the rapidly expanding whorls, non-shouldered convex whorls and very close-set lamellae as differences from the Pliocene to Recent Atlanto-Mediterranean species. We agree with these authors and separate the two, recognizing the Turkish specimen as conspecific with L. costatissima . The teleoconch whorls of Hyaloscala pulchella are regularly increasing in width, whereas the last whorl is slightly allometrically widening in L. costatissima , which differs in its broad crests of the lamellae, whereas Hyaloscala pulchella forms thin lamellae (see Weil et al. 1999: fig. 101; note that Chirli 2009: pl. 13, figs 11–17 is probably not this species). The presence of three large varices on the last whorls also distinguishes the Miocene species. The protoconch of L. costatissima is high conical of five whorls but slender, turreted as opposed to four whorls in H. pulchella (see Landau et al. 2006: pl. 11, fig. 3).

Paleoenvironment. The occurrence in the Baden Formation suggest middle to outer neritic environments ( Kranner et al. 2021), whereas the specimen from Seyithasan ( Turkey) derives from a shallow water assemblage.

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

Proto-Mediterranean Sea. Serravallian (Middle Miocene): Karaman Basin: Seyithasan ( Turkey ( Landau et al. 2013).

Genus Mazescala Iredale, 1936 View in CoL

Type species. Mazescala thrasys Iredale, 1936 View in CoL ; original designation by Iredale (1936: 296). Present-day, Australia.

Diagnosis. “ Scaloid shells with whorls tightly coiled and not umbilicated, lamellae erect and numerous, apical whorls thin and glassy, whorls numerous subshouldered.” ( Iredale 1936: 296).

Discussion. Although Mazescala is treated as synonym of Epitonium Röding, 1798 by MolluscaBase eds (2024g) we follow Iredale (1936) and Weil et al. (1999), who accepted Mazescala at genus or subgenus rank. Weil et al. (1999: 212) used this genus for species resembling Hyaloscala de Boury, 1890 [type species Turbo clathratulus Kanmacher, 1798 ; present-day, eastern Atlantic] but which have numerous convex whorls, a strongly impressed suture and thin, strongly raised lamellae. Hirtoscala Monterosato, 1890 [type species Scalaria cantrainei Weinkauff, 1866 ; present-day, Mediterranean Sea] differs in its more solid, gradate whorls and more prominent lamellae fused from one whorl to the other over the sutures. In our opinion, Mazescala comprises a group of quite distinctive, small to medium-sized, thin-shelled species, which are characterized by convex whorls with more or less distinct shoulder angulation, deeply impressed suture and numerous thin lamellae often forming short spines along the shoulder. The shells lack a peribasal cord but usually have a weak basal angulation with flattish base. The lamellae persist on the base where they have strongly rolled over crests. The very thin lamellae are frequently damaged resulting in a somewhat ‘tattered’ appearance of some specimens. The genus is documented by several extant species from Australia [ Mazescala bellicosa ( Hedley, 1907) , M. thrasys Iredale, 1936 , M. heloris Iredale, 1936 ] and Japan [ Mazescala koyamai ( Nakayama, 1995) , M. sakuraii (Kuroda & Habe, 1961) , M. sawamurai ( Azuma, 1960) ]. In most epitoniid genera the presence/absence of spirals is a generic character. In this genus the interspaces can be smooth or have very faint spirals. Most species are found in deeper marine environments. The Pliocene to Pleistocene Mediterranean Mazescala salicensis ( Seguenza 1876) and the herein described species from the Middle Miocene of the Paratethys are the only fossil occurrences known to us.