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Conus (Dendroconus) pyruloides (Pietro Doderlein, 1862 - Sacco, 1893)
Conus (Dendroconus) eschewegi var. caelata (Doderlein, 1862 - Sacco, 1893)
Conus (Lautoconus) eschewegi ( Pereira da Costa, 1866)
Descrizione e caratteristiche:
Sacco, descrisse questa specie basandosi sugli esemplari originali del Doderlein ed afferma che questa specie si collega strettamente al C. berghausi(1), e la forma generale del Conus berghausi potrebbe dargli ragione (columella, scultura alla base, attacco dell’apertura….=; Muniz lo mette in relazione con il Conus eschewegi (2).
Alcuni esemplari giovani conservati al Museo geol. di Modena(*) erano identificati come C. nisus, specie recente, o come C. pyriformis (Doderlein) (1).
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Lautoconus eschewegi (4)
Revised description. Medium-sized, pyriform shells; extraordinarily pointed, turreted early spire (but poorly preserved in all specimens); later spire low conical to cyrtoconoid with channelled suture; spiral whorls slightly convex; subsutural flexure very shallow, weakly curved, moderately asymmetrical; shoulder strongly rounded, slightly subangulate in fully grown shells. Last whorl elongate and conical, constricted at base. Moderately long, broad and reflected siphonal canal; aperture moderately wide, slightly widening anteriorly. Siphonal fasciole swollen, strongly twisted, not well demarcated from base and straight, broad inner lip. Few wavy spiral grooves on base demarcating broad spiral cords. Colour pattern consisting of slightly irregularly spaced spirals formed by short dashes and subquadratic dots; size of dots rather homogenous within a spiral but may vary in size and density between spirals; sometimes two spirals form a close-spaced pair with nearly amalgamating dots. Dots become axially elongate on shoulder, rarely forming an inverted “Y”; narrow axially elongated stripes on spire whorls.
Shell measurements and ratios. n = 7: largest specimen: SL: 42.8 mm, MD: 23.8 mm, mean SL: 37.4 mm (σ = 3.5), mean MD: 20.8 mm (σ = 2.1), spire angle: µ = 113.3° (σ = 8.6°), last whorl angle: µ = 37.0° (σ = 1.4°), LW: µ = 1.8 (σ = 0.04), RD: µ = 0.63 (σ = 0.01), PMD: µ = 0.86 (σ = 0.01), RSH: µ = 0.12 (σ = 0.03).
Discussion. Tucker & Tenorio (2009) proposed a placement of this species in Lautoconus Monterosato, 1923. The completely smooth spire whorls, which lack any sculpture even on earliest teleoconch whorls and the mode of siphonal canal formation would perfectly fit in Varioconus da Motta, 1991, which however is currently considered to be a junior synonym of Lautoconus ( Puillandre et al. 2014a, b).
Hoernes & Auinger (1979) illustrated three shells as “ Dendroconus subraristriatus ”, which represent three different species, of which none is conspecific with Lautoconus subraristriatus (Pereira da Costa, 1866). The reason for uniting these different morphologies in a single species was the superficial similarity in colour patterns and the also much too broad species concept of Pereira da Costa (1866) (see Landau et al. 2013 and discussion of Lautoconus subraristriatus).
The original description of Lautoconus eschewegi (Pereira da Costa, 1866) united several morphotypes, which are most probably not conspecific. Therefore, Sacco (1893a) designated the slender, pyriform specimen illustrated by Pereira da Costa (1866, fig. 23) as type of this species. This species was also described as Conus pyruloides Sacco, 1893, from the late Miocene of Italy, which was considered to be a junior synonym of L. eschewegi by Hall (1966) and Davoli (1972). In the material from Letkés in the collection of the NHMWAbout NHMW, this species is easily recognised under UV light by its conspicuous and intense colour pattern. This also allows the identification of subadult shells, which have a weaker siphonal fasciole, shorter siphonal canal and an evenly rounded shoulder. Therefore, we consider the specimens identified by Kovács & Vicián (2013) as Lautoconus belus (d’Orbigny, 1852) and L. pyrula ( Brocchi, 1814) to represent different morphotypes and growth stages of L. eschewegi. Moreover, Lautoconus belus sensu Hall (1966, pl. 22, figs 15–16)and Muñiz-Solís (1999, figs 7A–B) differs from the Paratethyan species in its broader outline, better defined shoulder and the conspicuous spiral sculpture on the last whorl and L. pyrula has a strong spiral sculpture on the base, a much weaker fasciole and a well-defined shoulder.
Muñiz-Solís (1999) described Conus eschewegi from the lower upper Pliocene of Estepona. These specimens develop a comparatively broad conical last whorl and are most probably not conspecific with L. eschewegi. The superficially similar Kalloconus fuscocingulatus (Hörnes, 1851) differs in the colour pattern of continuous spirals and the tuberculate spire whorls.
Paleoenvironment. Probably shallow marine environments based on the coral-associated assemblages at species Letkés in Hungary ( Kovács & Vicián 2013).
Distribution in Paratethys. Badenian (middle Miocene): Transylvanian Basin: Lăpugiu de Sus ( Romania); Pannonian Basin: Pannonian Basin: Várpalota, Letkés ( Hungary) ( Szalay 1926; Kovács & Vicián 2013).
Proto-Mediterranean Sea and northeastern Atlantic. Tortonian: Cacela Basin: Cacela Velha (Portugal) (Pereira da Costa 1866); Sant'Agata Fossili, Stazzano, Montegibbio (Po Basin, Italy) ( Sacco, 1893a; Davoli 1972); Casa Nova Calises, Forlì (Apennines, Italy) ( Ruggieri & Davoli 1984); Messinian: Borelli (Turin Hills) ( Davoli 2003). The early Pliocene occurrences from Vezza d’Alba and Asti (Po Basin, Italy) need confirmation ( Davoli 1972).
Distribuzione:
Tortoniano (1)
(*) Museo di Paleontologia di Modena: Collezioni Doderlein – Coppi – Pantanelli - Foresti
(**) Conus hornesi (Doderlein)
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Toscana
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Conus (Lautoconus) eschewegi ( Pereira da Costa, 1866)
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Bibliografia Consultata
(4) - Harzhauser, Mathias & Landau, Bernard, 2016, A revision of the Neogene Conidae and Conorbidae (Gastropoda) of the Paratethys Sea, Zootaxa 4210 (1), pp. 1-178: 106-108 Lautoconus eschewegi
(8) - Davoli (1972) “Conidae (Gastropoda) Studi monografici sulla malacologia miocenica modenese, Parte I. I molluschi tortoniani di Montegibbio. Palaeontographia Italica, V. 68: 51-143.”
