Mangelia larga, Scarponi & Bella & Dell’Angelo & Huntley & Sosso, 2016

Scarponi, Daniele, Bella, Giano Della, Dell’Angelo, Bruno, Huntley, John Warren & Sosso, Maurizio, 2016, Middle Miocene conoidean gastropods from western Ukraine (Paratethys): Integrative taxonomy, palaeoclimatogical and palaeobiogeographical implications, Acta Palaeontologica Polonica 61 (2), pp. 327-344 : 332-333

publication ID	https://doi.org/ 10.4202/app.00158.2015
persistent identifier	https://treatment.plazi.org/id/A8608798-FF81-FFB3-1F63-71D5FDF043D5
treatment provided by	Felipe
scientific name	Mangelia larga
status	sp. nov.

Treatment

Mangelia larga View in CoL sp. nov.

Figs. 3B View Fig , 4B, C View Fig , 5B− D View Fig ; SOM 1: fig. 3B, SOM 2.

Etymology: From Latin larga , inflated, wide; named after the distinctive, inflated teleoconch whorls.

Type material: Holotype, MGGC-24507 , adult, fairly preserved shell, outer lip slightly broken . Paratypes, MGGC-24508 /1–14 from the type locality (SOM 2) .

Type locality: Varovtsi , Ukraine .

Type horizon: Massive, white sandstone of the Pidhirtsi Beds, early Serravallian (~14.0−12.7 Ma).

Material.— Thirteen topotype specimens from Varovtsi: IGS-NANU-B-I-2-3/2015 (2 shs), MNHN.F.A53760 (2 shs), MSNG-58188 (2 shs), MGPT-PU135045 (2 shs), NHMW-2015 /0404/0002 (3 shs), ZISP-62074 (2 shs); one from Horodok: IGS-NANU-B-I-2/2015 .

Diagnosis.—A very small Mangelia species (shell lengthm 4.4 mm, sd 0.8 mm; shell widthm 2.1 mm, sd 0.3 mm), characterised by a paucispiral protoconch (lengthm 0.38 mm, sd 0.02 mm; widthm 0.44 mm, sd 0.03 mm), a very short spire (0.29 the shell lengthm, sd 0.05), inflated teleoconch whorls and a bent columellar lip. Teleoconch sculpture of numerous, rounded, low ribs (max 14 on the second whorl), and a dense pattern of spiral elements of which the two most prominent are in correspondence with, and just below, the periphery.

Description.—Shell small-sized, fusiform, spire conical (0.29 the shell lengthm, sd 0.05); last whorl rounded. Protoconch paucispiral, of 1.2 convex whorls (sd 0.1 wh); nucleus large, smooth, remaining portion with numerous, irregularly spaced axial wrinkles overrun by weak cordlets strengthening at the protoconch-teleoconch boundary. The latter sometimes marked by a relatively thick axial scar. Teleoconchm of 4.0 (sd 0.6 wh) inflated whorls (first two slightly angulated), with noticeable axial and spiral sculpture; suture slightly undulating. Axial sculpture of rounded, relatively dense, orthocline ribs (usually 11 on second whorl), extending across the sutures, on the last whorl fading towards the base. Growth lines evident, especially near the adapical suture. Spiral sculpture of spaced threads; finer and relatively homogeneous on sutural ramp, varying in strength below periphery; commonly two to four elements thicker than the others. One of the largest marks the edge of the sutural ramp. Aperture moderately wide, lanceolate (lengthm 2.1 mm, sd 0.4 mm); siphonal canal relatively short. Outer lip thin-edged, convex in profile, internally thickened; anal sinus C-shaped; columellar lip bent.

Remarks.— Mangelia larga sp. nov. shows distinctive features; the combination of its: (i) small size (e.g., lengthm 4.0 mm), (ii) small paucispiral protoconch, (iii) dense axial sculpture (usually 11 ribs on the second whorl), (iv) characteristic spiral sculpture (threads of alternating strength), (v) inflated teleoconch whorls and (vi) fusiform profile, allows M. larga sp.nov. to be easily distinguished from species reported herein and from those reported in the literature (e.g., Laskarew 1914; Kautsky 1925; Friedberg 1951; Zelinskaya et al. 1968; Bałuk 2003, 2006; see also SOM 1 for further details). Hence, no further comparative analyses were performed.

Stratigraphic and geographic range.—Pidhirtsi Beds, early Serravallian of the Central Paratethys.