Plagioconus elatus ( Michelotti, 1847 )

Harzhauser, Mathias & Landau, Bernard, 2016, A revision of the Neogene Conidae and Conorbidae (Gastropoda) of the Paratethys Sea, Zootaxa 4210 (1), pp. 1-178 : 132-133

Plagioconus elatus ( Michelotti, 1847)

Figs 30 H, 32A1–A3, 32B1–B2

Conus elongatus nobis—Borson 1820: 198, pl. 1, fig. 4 [non Conus elongatus Holten, 1802 ].

Conus elatus mihi—Michelotti 1847: 341, pl. 13, figs 16–16’.

Conus Haueri Partsch—Hörnes 1851: 34 (partim), pl. 4, figs 4a–b? [non fig. 5 = Plagioconus puschi ( Michelotti, 1847) ].

Conus (Leptoconus) Haueri Partsch—Hoernes & Auinger 1879: 33 (partim).

[ Conus ] Leptoconus elatus (Micht.) — Sacco 1893a: 35.

Conus (Leptoconus) haueri (Partsch in Hörnes 1856) —Kojumdgieva in Kojumdgieva & Strachimirov 1960: 210, pl. 49, fig. 1.

Conus (Chelyconus) austriaconoae Sacco 1893 —Kojumdgieva in Kojumdgieva & Strachimirov 1960: 212, pl. 50, fig. 2 [non Conus austriaconoe d’Orbigny, 1852 ].

Conus elongatus Borson—Pavia 1976: 157 , pl. 2, fig. 11.

Conus (Leptoconus) elongatus Borson, 1820 — Bałuk 2006: 216, pl. 16, fig. 8.

Plagioconus elatus ( Michelotti, 1847) — Tucker & Tenorio 2009: 111, pl. 6, fig. 5.

Type material. Syntype or holotype illustrated by Michelotti (1847, pl. 13, fig. 16), Tortona, Italy; the specimen might have been stored in the collections of the Dipartimento di Scienze della Terra, Sapienza Università di Roma but parts of the Michelotti collection were destroyed during WWII ( Manni 2005); type specimen is lost according to Hall (1966); late Miocene, Tortonian.

Studied material. 1 spec. NHMW 1997z0178/1471, 1 spec. NHMW 1856/0050/0114, 4 spec. NHMW 1855/ 0045/0367, 1 spec. NHMW 1997 z0178/1473, Gainfarn ( Austria); 1 spec . NHMW 1846 /0037/0023, Grinzing ( Austria).

Illustrated material. Figs 32A 1 –A3: Gainfarn ( Austria): SL: 91.6 mm, MD: 38.4 mm, NHMW 1855/0045/ 0367; Figs 30 H, 32B1–B2: Grinzing ( Austria): SL: 103.8 mm, MD: 37.3 mm, NHMW 1846/0037/0023.

Revised description. Large shells; spire short with coeloconoid outline. Teleoconch comprising at least 12 whorls; early spire whorls beaded, rounded or with weak angulation in the middle, migrating towards lower suture on last whorls. Suture deeply incised, emphasized by weak subsutural inflation; delicate spiral threads appear on sutural ramp. Subsutural flexure deep, moderately curved, strongly asymmetrical. Last whorl slightly allometric in growth due to rapid widening of last two whorls. Sutural ramp relatively shallow and wide, distinctly shouldered at periphery, whorl straight below, hardly constricted at base. Aperture narrow; siphonal canal of moderate length and width; not recurved or twisted. Narrow, flattened inner lip demarcated from short fasciole by distinct notch. No spiral grooves on base. No colour pattern is preserved.

Shell measurements and ratios. n = 8 adult and subadult specimens: largest specimen: SL: 103.8 mm, MD: 39 mm, mean SL: 87.9 mm (σ = 8.1), mean MD: 35.4 mm (σ = 2.6), spire angle: µ = 82.4° (σ = 3.3°), last whorl angle: µ = 24.5° (σ = 1.2°), LW: µ = 2.48 (σ = 0.15), RD: µ = 0.50 (σ = 0.03), PMD: µ = 0.96 (σ = 0.01), RSH: µ = 0.19 (σ = 0.02).

Discussion. This species was frequently treated as Conus elongatus Borson, 1820 (e.g. Hall 1966; Davoli 1972; Bałuk 2006). This name, however, is preoccupied by C. elongatus Holten, 1802 and consequently C. elatus Michelotti, 1847 is the next available name. In the Paratethys, it was identified as Conus haueri Hörnes, 1851 , which is a problematic species. The syntype illustrated by Hörnes (1851, pl. 4, fig. 4) is lost and the spire whorls of the illustration display a weak concavity as typical for Monteiroconus antiquus . The syntype illustrated by Hörnes (1851, pl. 4, fig. 5) is still preserved in the NHMW collection and is a specimen of Plagioconus puschi . The syntype of Conus haueri from Grinzing mentioned by Hörnes (1851, not illustrated) and all other shells identified as C. haueri in the NHMW collection agree fully with Plagioconus elatus ( Michelotti, 1847) as understood by Hall (1966). Therefore, we consider Conus haueri Hörnes, 1851 a nomen dubium.

Paleoenvironment. All Austrian specimens were found in assemblages from shallow sublittoral settings (e.g. Zuschin et al. 2007).

Distribution in Paratethys. Badenian (middle Miocene): Vienna Basin: Gainfarn, Grinzing ( Austria); Pannonian Basin: Szob ( Hungary) ( Hoernes & Auinger 1879); Carpathian Foredeep: Korytnica ( Poland) ( Bałuk 2006); Dacian Basin: Opanec ( Bulgaria) ( Kojumdgieva & Strachimirov 1960).

Proto-Mediterranean Sea and northeastern Atlantic. Burdigalian ( Italy: Colli Torinesi), Tortonian ( Italy: Sant'Agata Fossili, Stazzano Montegibbio). A Pliocene occurrence from Borzoli ( Italy) was mentioned by Sacco (1893a) but needs confirmation.

Figures

FIGURE 1. Map of central and south – eastern Europe showing the geographic position of selected localities with rich Conidae diversities (modified from Kováč et al. 2007). 1: Korytnica (Poland), 2: Podhorce, Zukowce, Biłka, Tarnopol (Ukraine), 3: Grund, Guntersdorf, Immendorf (Austria), 4: Steinebrunn (Austria), Mikulov (Czech Republic), 5: Gainfarn, Enzesfeld, Baden, Bad Vöslau, Baden-Sooß (Austria), 6: Ritzing (Austria), 7: Weitendorf, Pöls (Austria), 8: Letkés, Szob (Hungary), 9: Borsodbóta (Hungary), 10: Várpalota (Hungary), 11: Hidas (Hungary), 12: Coşteiu de Sus, Lăpugiu de Sus (Romania).

FIGURE 32 A 1 – A 3. Plagioconus elatus (Michelotti, 1847), Gainfarn (Austria), NHMW 1855 / 0045 / 0367. 32 B 1 – B 2. Plagioconus elatus (Michelotti, 1847), Grinzing (Austria), NHMW 1846 / 0037 / 0023. 32 C 1 – C 3. Plagioconus extensus (Hörnes, 1851), Lăpugiu de Sus (Romania), NHMW 1890 / 0001 / 0011. 32 D. Plagioconus extensus (Hörnes, 1851), Lăpugiu de Sus (Romania), NHMW 1859 / 0037 / 0001. 32 E 1 – E 3. Plagioconus extensus (Hörnes, 1851), Baden-Sooß (Austria), NHMW 1872 / 0030 / 0017. 32 F 1 – F 3. Plagioconus marii (Sacco, 1893), Baden-Soo (Austria), NHMW 2013 / 0300 / 0529. 32 G 1 – G 3. Plagioconus marii (Sacco, 1893), Vöslau (Austria), NHMW 1846 / 0037 / 0025. 32 H. Plagioconus hirmetzli (Kovács & Vicián, 2013), Letkés (Hungary), private collection of T. Hirmetzl, paratype. 32 I. Plagioconus hirmetzli (Kovács & Vicián, 2013), Letkés (Hungary). private collection of T. Hirmetzl, paratype. 32 J. Plagioconus hirmetzli (Kovács & Vicián, 2013), Letkés (Hungary), HNHM, PAL 2013.3. 1, holotype.