Vexillum intermittens
Creators: name: Harzhauser, Mathias
name: Landau, Bernard
Publisher: name: Zenodo
Year: 2021
Subjects: Biodiversity
Taxonomy
Animalia
Mollusca
Gastropoda
Neogastropoda
Costellariidae
Vexillum
Vexillum intermittens

description: Vexillum intermittens (Hoernes & Auinger, 1880)
Figs 4M, 16E 1 –E 2, F 1 –F 2, G 1 –G 2, H 1 –H 2
Costellaria intermittens n. form.—Hoernes 1880: 125 [nomen nudum].
* Mitra (Costellaria) intermittens n. form.— Hoernes & Auinger 1880: 85, pl. 10, figs 1–4.
[Turricula] intermittens R. Hoern. — Cossmann 1899: 166.
V [exillum]. (C [ostellaria].) intermittens (R. Hörn, et Au.)— Sieber 1958a: 153.
Vexillum (Costellaria) intermittens (R. Hörn. Auing.) — Sieber 1958b: 149.
non Vexillum (Costellaria) intermittens (Hoernes et Auinger) —Kojumdgieva in Kojumdgieva & Strachimirov 1960: 161, pl.
42, figs 11a–b [=?]. non Mitra (Vexillum) intermittens Hoernes & Auinger, 1880 — Strausz 1966: 368, pl. 25, figs 9–10 [= Vexillum szobbiensis
Halaváts, 1884]. non Vexillum (Costellaria) intermittens (R. Hörnes et Auinger) — Stancu et al. 1971: 125, pl. 7, fig. 9 [=?].
Type material. Lectotype (designated herein): NHMW 1846 /0037/0105: Bad Vöslau (Austria), SL: 14.0 mm, MD: 4.6 mm, illustrated in Hoernes & Auinger (1880, pl. 10, figs 2a–c), figs 16G 1 –G 2. Paralectotypes: NHMW 1863 /0015/0624: Bad Vöslau (Austria), SL: 17.7 mm, MD: 4.8 mm, illustrated in Hoernes & Auinger (1880, pl. 10, figs 3a–c), figs 16E 1 –E 2; NHMW 2020 /0087/0001: Baden or Bad Vöslau (Austria), SL: 14.4 mm, MD: 4.2 mm, illustrated in Hoernes & Auinger (1880, pl. 10, figs 1a–c), figs 16F 1 –F 2; NHMW 2020 /0087/0002: Baden or Bad Vöslau (Austria), SL: 12.2 mm, MD: 3.4 mm, illustrated in Hoernes & Auinger (1880, pl. 10, figs 4a–c), figs 16H 1 –H 2. NHMW 2020 /0087/0003: Baden or Bad Vöslau (Austria), SL: 15.3 mm, MD: 4.0 mm, fig 4M; NHMW 2020 /0087/0004, 26 specimens, Baden or Bad Vöslau (Austria).
Revised description. Shell moderately large, slender fusiform, with high conical spire. Protoconch (fig. 4M) high conical, of three smooth, weakly convex whorls (height: 990 μm, diameter: 740 μm). Teleoconch of seven straight-sided to faintly convex whorls, with periphery close above abapical suture; suture deeply incised. Last whorl slightly more convex or subcylindrical, strongly constricted at base. Sculpture of first three to four teleoconch whorls consisting of seven to ten broad, convex, weakly opisthocline axial ribs, separated by slightly wider interspaces. Axial ribs usually weakening on middle spire whorls, reappearing on penultimate and last whorls, typically fading out towards adapical suture and slightly swollen towards abapical suture. Axial sculpture fading out on last whorl below periphery. Rarely, axial sculpture persisting throughout growth, or completely reduced on last whorl. Aperture moderately narrow, elongate; columellar callus indistinct. Columella with four folds, weakening abapically; fourth fold very weak and short. Outer lip thin, 10 to 16 delicate, subparallel lirae within. Spiral sculpture represented by few faint spiral threads visible only under strong magnification; five prominent spiral cords on weak fasciole. Siphonal canal moderately long, moderately narrow, straight, with wide and shallow anterior notch.
Shell measurements and ratios. SL: 12.2–17.7 mm, MD: 3.4–4.8 mm; AA: 25–28°, SL/MD: 3.2–3.5, AL/AW: 4.4–5.1, AH/S: 2.1–2.4.
Discussion. This species displays little variability in shape and size, but varies considerably in sculpture. In most specimens, spiral sculpture is absent or strongly reduced along the last two or three spire whorls. Vexillum intermittens (Hoernes & Auinger, 1880) is documented so far only from the type area of Baden and Bad Vöslau in Austria. Other Paratethyan occurrences are misidentifications; e.g. Kojumdgieva in Kojumdgieva & Strachimirov (1960) described a specimen from the Badenian of Bulgaria, which differs from V. intermittens in its extraordinarily slender and smooth shell. The specimen from Letkés (Hungary), described by Strausz (1966) develops spiral cords in the axial interspaces and is most probably conspecific with Vexillum szobbiensis (Halaváts, 1884).
Palaeoenvironment. The species is only found so far in clay of the Baden Formation suggesting middle neritic settings with up to 250 m water depth (Hohenegger et al. 2008).
Distribution in Central Paratethys. Badenian (middle Miocene): Vienna Basin: Baden-Sooss, Bad Vöslau, Baden (Austria) (Hoernes & Auinger 1880).
description: Published as part of Harzhauser, Mathias & Landau, Bernard, 2021, An overlooked diversity-the Costellariidae (Gastropoda: Neogastropoda) of the Miocene Paratethys Sea, pp. 1-70 in Zootaxa 4982 (1) on page 51, DOI: 10.11646/zootaxa.4982.1.1, http://zenodo.org/record/4921842