Turritellinella subuliformis ( Boettger, 1907 ) Harzhauser & Landau, 2019

Harzhauser, Mathias & Landau, Bernard, 2019, Turritellidae (Gastropoda) of the Miocene Paratethys Sea with considerations about turritellid genera, Zootaxa 4681 (1), pp. 1-136 : 76-77

Turritellinella subuliformis ( Boettger, 1907) new comb.

Figs 6 Aj, 20A 1 –A 2, 20B 1 –B 2

* Turritella communis Risso var. subuliformis n. — Boettger, 1907: 165, no. 572.

Turritella communis subuliformis Boettger — Zilch, 1934: 216, pl. 6, fig. 8.

? Turritella communis subuliformis Boettger — Csepreghy-Meznerics, 1956: 384, pl. 2, figs 31–33.

? Turritella aff. communis Risso, 1826 — Strausz, 1966: 103, pl. 3, fig. 20.

Turritella (Turritella) communis subuliformis Boettger, 1907 — Bałuk, 1975: 103, pl. 12, figs 14–16.

Type material. Lectotype, SMF XII 2489 a, paralectotype SMF XII 2490 b, coll. O. Boettger, stored in the Senckenberg Museum in Frankfurt am Main ( Germany). Coşteiu de Sus, Fântânâ bâtrina ( Romania), Badenian, middle Miocene.

Studied material. 1 spec. NHMW 2018/0181/0008, 1 spec. NHMW 2018/0181/0009, 2 spec. NHMW 1854/0035/0306, 24 spec. NHMW 1870/0033/0160, Lăpugiu de Sus ( Romania) ; 2 spec. NHMW 2010/0004/0447, Bad Vöslau ( Austria) .

Illustrated material. Figs 20A 1 –A 2 : NHMW 2018/0181/0008, SL: 29.3 mm, MD: 7.6 mm, Figs 20B 1 –B 2 : NHMW 2018/0181/0009, SL: 17.6 mm, MD: 4.1 mm, Lăpugiu de Sus ( Romania).

Revised description. Shell small, thin, moderately slender of 16 teleoconch whorls. Protoconch unknown. First two neanic whorls tricostate (order of appearance unclear). One secondary spiral cord intercalated between A/B cords on third teleoconch whorl; additional secondary cord between B/C on fourth whorl. Subsequently spiral cords quickly increasing by intercalations of additional secondary and tertiary spiral cords; primary spiral cords soon weaken distinctly, being hardly distinguished from secondary cords. Spiral cords weakly papillate on early whorls. Last teleoconch whorls covered by about 20 narrow primary, secondary and tertiary spiral cords with convex tops, separated by slightly broader interspaces. Teleoconch whorls evenly convex or faintly angulated at mid-whorl, coinciding with B spiral cord. Up to 10 discontinuous spiral plicae appear on the inner side of teleoconch whorls, being most prominent close to the abapical suture. Lateral sinus angle moderately steep; deep with well-defined vertex; faint adapical and abapical inflection points; central LS p. Basal sinus distinctly opisthocyrt. Transition into base angulated. Base weakly convex with numerous delicate spiral threads. Aperture subcircular to subquadrate; inner lip reflected; parietal callus expanding, covering large parts of base.

Shell measurements and ratios. Only few complete specimens available; largest specimen: 29.3 mm, MD: 7.6 mm. AA° 20–22°, PA°: 14–16°. Lateral sinus (n = 5): LS angle = 17.6° (σ = 2.1°), LS p = 1.0 (σ = 0.1), LS d = 4.7 (σ = 1.0).

Discussion. Landau et al. (2004) treated the middle Miocene Paratethyan occurrences as Turritella tricarinata ( Brocchi, 1814) . Indeed, the neanic whorls of both taxa are identical (see Figs 20C 1 –C 2 ), NHMW 2018/0302/0001, SL: 30.2 mm, MD: 7.9 mm, Adriatic Sea). Nevertheless, the delicate sculpture of tertiary and secondary spiral cords and the strong reduction of the primaries, along with the evenly convex whorls, distinguish Turritellinella subuliformis from Turritellinella tricarinata , which is also larger. In addition, the lateral sinus of T. subuliformis is deeper and has a narrower vertex. Therefore, we prefer to separate the Paratethyan taxon as distinct species.

Several authors identified middle Miocene Paratethyan specimens as ‘ Turritella communis ’ and ‘ Turritella tricarinata ’; e.g. by Sieber (1960: 251, pl. 1, fig. 27), Hinculov (1968: 134, pl. 32, figs 6a–6b), Stürmer (1989: 128, pl. 4, fig. 10, pl. 12, fig. 6), and Mikuž (2009: 11, pl. 1, fig. 19). Sieber (1960) mentioned this Recent European spe- cies from the middle Miocene of Steinebrunn ( Austria). The single available specimen described by Sieber (1960) and Stürmer (1889) (NHMW 1963/0519/0000) is 13 mm in height and 4.5 mm in diameter and has an PA of 19°. Thus, it is much broader than Turritellinella tricarinata and the middle Miocene T. subuliformis ( Boettger, 1907) . The spire whorls are low, angulated in the abapical third bearing two prominent spiral cords. This spire fragment is reminiscent of Turritella gradata and Zaria aquitanica at same growth stage, both of which are unknown from the locality Steinebrunn. Most probably, the provenience from Steinebrunn of the specimen discussed by Sieber (1960) and Stürmer (1889) (NHMW 1963/0519/0000) is incorrect. Other occurrences are based on unidentifiable fragments ( Hinculov 1968) or might rather represent specimens of Ptychidia vindobonensis ( Handmann, 1882) ( Mikuž 1982, 2009). None of these specimens is conspecific with Turritellinella tricarinata or T. subuliformis .

Paleoenvironment. The occurrences in offshore clays at Bad Vöslau, Lăpugiu de Sus and Coşteiu de Sus might indicate a preference for middle to outer neritic environments and soft bottom habitats.

Distribution. Central Paratethys. Badenian (middle Miocene): Carpathian Foreland Basin: Korytnica ( Poland) ( Bałuk 1975); Vienna Basin: Bad Vöslau ( Austria) (herein); Transylvanian Basin: Lăpugiu de Sus, Coşteiu de Sus ( Romania) ( Boettger 1907; herein); Pannonian Basin?: Szob ( Hungary) ( Strausz 1966); Cserhát Mountains ( Hungary) ( Strausz 1966).

Figures

FIGURE 1. Paleogeography of the Paratethys during the early Miocene (Burdigalian, Eggenburgian, Sakaraulian) and the middle Miocene (Langhian, Badenian, Tarkhanian) (modified after Popov et al. 2004 and Neubauer et al. 2015).

FIGURE 2. Miocene chronostratigraphy after Gradstein et al. (2012) with regional Paratethys stages after Popov et al. (2004) and Piller et al. (2007).

FIGURE 6. Growth line traces of Turritellidae species based on own data; bold: type species of genera; black: Paratethyan species; asterisk: non-Paratethyan species (unknown basal sinuses are left blank).

FIGURE 20. A–B. Turritellinella subuliformis (Boettger, 1907), Lăpugiu de Sus (Romania, A1–A2. NHMW 2018/0181/0008. B1–B2. NHMW 2018/0181/0009. C1–C2. Turritellinella tricarinata (Brocchi, 1814), Adriatic Sea, NHMW 2018/0302/0001.