Scaevatula sidoniae Harzhauser & Landau & Janssen 2022, nov. comb.
Creators: name: Harzhauser, Mathias
name: Landau, Bernard
name: Janssen, Ronald
Publisher: name: Zenodo
Year: 2022
Subjects: Biodiversity
Taxonomy
Animalia
Mollusca
Gastropoda
Neogastropoda
Clavatulidae
Scaevatula
Scaevatula sidoniae

description: Scaevatula sidoniae (Hoernes & Auinger, 1891) nov. comb.   
 Figs 42A 1 –A 3, 4I, 4 Ac, 5, 7   
 Clavatula Sidoniae —Hoernes 1891: 129 [nomen nudum].   
 * Pleurotoma (Clavatula) Sidoniae nov. form.— Hoernes & Auinger 1891: 339, pl. 43, figs 3a–b.   
 Clavatula sidoniae (Hoernes & Auinger, 1891) — Kovács & Vicián 2021: 143, pl. 2, figs 10–11.   
 Type material. Holotype: NHMW 1855 /0043/0045, SL: 24.8 mm, MD: 8.2 mm, Lăpugiu de Sus (Romania), illustrated in Hoernes & Auinger (1891, pl. 43, figs 3a–b), figs 42A 1 –A 3, 4I, 4Ac.   
 Revised description. Shell medium-sized, solid, moderately slender fusiform, with high, conical spire; apical angle ~29°. Protoconch only partly preserved comprising one low, convex whorl with broad axial ribs. Transition to teleoconch marked by appearance of suprasutural row of beads. Teleoconch of up to twelve whorls. Early teleoconch whorls flat-sided, bearing weakly beaded subsutural spiral cord and prominent suprasutural row of larger beads, separated by narrow spiral groove. Abapically subsutural row of beads becomes subsutural collar bearing somewhat coalescent beads, beads remain poorly defined throughout ontogeny. Central spiral groove widens, suprasutural beads enlarge becoming markedly axially elongated tubercles and later ribs overridden by 2–3 narrow, weak spirals. Entire shell covered by extremely fine, delicately granulose spiral threads, most prominent in axial interspaces. Suture indistinct on early spire whorls, narrowly impressed in late teleoconch whorls. Last whorl 52% of total height. Subsutural ramp narrow, convace, bearing poorly defined tubercles, delimited by tubercular shoulder. Convex below, moderately constricted at base. Siphonal fasciole rounded, twisted. Sculpture of seven indistinctly tuberculose cords, three at mid-whorl, close set, four on base, narrower, wider-set and more distinctly tubercular, tubercles aligned axially to form vague axial ribs fine spiral cords over fasciole. Aperture moderately wide, ovate. Outer lip not thickened, with about 14 narrow lirae extending deep within aperture. Anal sinus moderately narrow, moderately deep, symmetrically U-shaped, with apex at mid-ramp. Siphonal canal moderately short, slightly deflected, shallowly notched at tip. Columella weakly excavated, twisted at fasciole, smooth. Columellar callus thickened abapically and in parietal region, thinner along middle ofaperture. Callus well delimited from base, fasciole, and parietal region but less so along middle of aperture.   
 Discussion. This species is unique within Paratethyan Clavatulidae in that a large amount of the spire whorls is exposed, so that axial ribs are seen on later whorls below the concave central portion. In all other clavatulids only a narrow portion of the whorl below the concave mid-portion is not covered by the succeeding whorl, so that is appears as if they have a suprasutural row of tubercles/beads. In some species, even these are almost completely obscured. The placement of this species in Scaevatula is based on the peculiar protoconch with blunt axial ribs. This is also unique amongst clavatulids. Moreover, the general mode of sculpture formation agrees well with that of the extant Scaevatula amancioi Rolán & Fernandes, 1993 from São Tomé (Gulf of Guinea), but in the modern species the nodes on the subsutural collar are axially elongated, and the subsutural concavity is shallower. Scaevatula pellisserpentis Gofas, 1990 differs in being sinistral and has different sculpture, in which small, rounded tubercles develop at the intersections where the narrow axial ribs are overrun by equally narrow spiral cords, forming a fine reticulated surface pattern.   
 Paleoenvironment. The occurrence at Letkés (Hungary) suggests a preference for inner neritic environments in the vicinity of corals (Kovács & Vicián 2013).   
 Distribution in Central Paratethys. Badenian (middle Miocene): Pannonian Basin: Letkés (Hungary) (Kovács & Vicián 2021); Făget Basin: Lăpugiu de Sus (Romania) (Boettger 1906).
description: Published as part of Harzhauser, Mathias, Landau, Bernard & Janssen, Ronald, 2022, The Clavatulidae (Gastropoda, Conoidea) of the Miocene Paratethys Sea with considerations on fossil and extant Clavatulidae genera, pp. 1-172 in Zootaxa 5123 (1) on page 141, DOI: 10.11646/zootaxa.5123.1.1, http://zenodo.org/record/6399827