Acrostemma edlaueri

Abstract

Acrostemma edlaueri (Berger, 1953) Figs 39B–C Retusa (Acrostemma) edlaueri n. sp. — Berger 1949: 82 [nomen nudum]. * Retusa (Acrostemma) edlaueri n. sp. — Berger 1953: 96, pl. 16, fig. 30. R [etusa]. (A [crostemma].) edlaueri Berg.— Sieber 1958: 163. Type material. Holotype, NHMW-ZOO-MO-75000-E-3310A, SL: 5.8 mm, MD: 2.2 mm, Bad Vöslau (Austria), Figs 39C 1 –C 3. Paratype, NHMW-ZOO-MO-75000-E-3310, Bad Vöslau (Austria), SL: 4.8 mm, MD: 1.8 mm, Bad Vöslau (Austria), Figs 39B 1 –B 3. Revised description. Medium sized, slender, elongate pyriform shell (SL/MD = 2.6–2.8), only last whorl visible. Protoconch unknown. Last whorl greatly elongated, weakly convex, periphery placed mid-whorl (SL/ PH = 1.9–2.0), almost straight above periphery, forming angle of about 23–28°. Rounded at slowly contracting base. Apex sharply truncated, moderately narrow (MD/ApD = 1.9–2.0), apical plane moderately oblique (AP = 14–15°), deeply and narrowly umbilicate, delimited by prominent, elevated, narrowly rounded apical crest, laterally protruding over adjacent whorl side. Surface of apical crest with close-set axial growth lines. Shell surface smooth except for moderately deep, apically fading spiral grooves over base. Aperture longer than shell, very narrow down to mid-whorl (MD/AW = 8.4–8.6), weakly widening anteriorly (MD/MAW = 2.5), resulting in moderate expansion rate (ER = 3.3–3.5). Outer lip thin, relatively high, narrowly alate apical extension. Columella short, distinctly excavated. Columellar callus forming delicate, narrow rim delimiting deep, narrow umbilical chink. Parietal callus not developed. Discussion. Landau et al. (2013) treated Acrostemma edlaueri (Berger, 1953) and Acrostemma kuehnelti (Berger, 1953) as subjective junior synonyms of Coelophysis latesulcata Boettger 1902 [= Pyrunculus latesulcatus (Boettger, 1902)]. This decision was based on the poor drawings in Berger (1953) and the poorly preserved holotype of Pyrunculus latesulcatus. Herein, we could study all type specimens and agree with Berger (1953) to treat all three taxa as distinct species. The type species Acrostemma coronata (Lamarck, 1804), from the Middle Eocene Lutetian of the Paris Basin, differs from Acrostemma edlaueri in its even slenderer shape and the absence of spiral sculpture (see Cossmann & Pissarro 1913: pl. 44, fig. 242-8). Acrostemma boutillieri (Cossmann, 1889), from the Upper Eocene Bartonian of the Paris Basin, has a broader apex and its outer lip rises only slightly above the apex (see Cossmann 1889: pl. 11, fig. 25). Acrostemma bezanconi (Morlet, 1885), also from the Upper Eocene of the Paris Basin, is more ovate with convex periphery, has a nearly straight columella and a more prominent apical spiral rim (see Cossmann 1889: pl. 11, fig. 12). Acrostemma tournoueri (Peyrot, 1932), from the Lower Miocene Aquitanian and Burdigalian of the Aquitaine Basin is slightly larger (SL: 7.5 mm), has a more convex periphery and a straight columella (see Peyrot 1932: pl. 12, figs 3–5). Paleoenvironment. The occurrence in the Baden Formation at Bad Vöslau (Austria) suggests middle to outer neritic environments with up to 210 m water depth (Kranner et al. 2021). Distribution in Central Paratethys. Badenian (Middle Miocene): Vienn Basin: Bad Vöslau (Austria) (Berger 1953).

Authors 3

1. Mathias Harzhauser

   Natural History Museum Vienna

   Affiliation as printed

   Natural History Museum Vienna, Burgring 7, 1010 Vienna, Austria mathias. harzhauser @ nhm. at; https: // orcid. org / 0000 - 0002 - 4471 - 6655

2. Bernard Landau Aachen

   University of Lisbon · Instituto Dom Luiz · Naturalis Biodiversity Center

   Affiliation as printed

   Naturalis Biodiversity Center, P. O. Box 9517, 2300 RA Leiden, Netherlands; Instituto Dom Luiz da Universidade de Lisboa, Campo Grande, 1749 - 016 Lisboa, Portugal; and International Health Centres, Av. Infante de Henrique 7, Areias São João, P- 8200 Albufeira, Portugal bernardmlandau @ gmail. com; https: // orcid. org / 0000 - 0002 - 7768 - 8494

3. Manuel António E. Malaquias

   University of Bergen · Natural History Museum Vienna

   Affiliation as printed

   Natural History Museum Vienna, Burgring 7, 1010 Vienna, Austria mathias. harzhauser @ nhm. at; https: // orcid. org / 0000 - 0002 - 4471 - 6655 & Department of Natural History, University Museum of Bergen, University of Bergen, PB 7800, 5020 - Bergen, Norway manuel. malaquias @ uib. no; http: // orcid. org / 0000 - 0002 - 9668 - 945 X & Natural History Museum Vienna, Burgring 7, 1010 Vienna, Austria mathias. harzhauser @ nhm. at; https: // orcid. org / 0000 - 0002 - 4471 - 6655