Conus (Lithoconus) gallicus (Mayer-Eymar, 1890)


Descrizione e caratteristiche:


E’ una conchiglia di piccole dimensioni, circa 20 – 30 mm. di lunghezza. La spalla è angolata e levigata. Alla base sono presenti alcune ben evidenti increspature. L’apertura è quasi diritta, con un debole allargamento alla base.

Le spire sono piano-concave, abbastanza elevate e presentano striature a spirale(1).

 

Kalloconus gallicus (4)

 

Revised description. Medium-sized shell; low conical spire with coeloconoid initial part; early spire whorls faintly striate, slightly concave; later whorls weakly convex; suture impressed. Subsutural flexure of medium depth, moderately curved, moderately asymmetrical. Narrow, rounded shoulder, coinciding with position of maximum diameter. Last whorl conical, straight sided with faint constriction at base. Aperture narrow with parallel margins; Siphonal canal short, nearly straight; siphonal fasciole very weak. Few wide-spaced spiral cords on base with weaker cords intercalating. Colour pattern on spire and last whorl consisting of irregular, strongly amalgamating dark blotches and few a light blotches.

Shell measurements and ratios. SL: 50.1 mm, MD: 31.9 mm, spire angle: 123°, last whorl angle: 37°, LW: 1.57, RD: 0.73, PMD: 0.90, RSH: 0.12.

Discussion. This species is characterised by the sloping last spire whorl, the narrow rounded shoulder and the narrow aperture. Nevertheless, the lack of any “extravagant” conchological features might raise doubts about the identification of the middle Miocene Paratethyan shell with an early to middle Miocene species from the northeastern Atlantic. Fortunately, the identification is supported by the unusual colour pattern, which was documented by Caze et al. (2011) also for an early Miocene specimen from the Aquitaine Basin.

Kalloconus tietzei ( Hoernes & Auinger, 1879) is broader, has a stronger siphonal fasciole, a wider anterior part of the aperture and differs in its colour pattern of spiral dashes. Some specimens ofKalloconus berghausi ( Michelotti, 1847), as illustrated by Davoli (1972), develop a comparable outline but differ in their wider last whorl aside from the punctate colour pattern of K. berghausi. The occurrence of this species in the Pliocene of the Mediterranean Sea will need confirmation. The specimens from Asti ( Italy) described by Hall (1966) agree in shape but no information on colour patterns is available. Other Pliocene specimens described as Conus gallicus by Muñiz-Solís (1999) and Paganelli (2014) are rather slender and have less sloping shoulders.

Distribution in Paratethys. Badenian (middle Miocene): Transylvanian Basin: Nemeşeşti ( Romania) (own data).

Proto-Mediterranean Sea and northeastern Atlantic. early Miocene (Aquitanian, Burdigalian): Aquitaine Basin: Larriey, Saucats, Merignac ( Mayer-Eymar 1890); Turin Hills: Termofourà (Italy) ( Hall 1966);? Pliocene: Po Basin: Asti (Italy) ( Hall 1966).

 


Distribuzione:

In Francia nell’Aquitaniano e nel Burdigaliano.

In Italia (Piemonte) nel Burdigaliano e nell’Astiano; in Toscana.

 


 

 

Conus gallicus

(da Peyrot)

 

Conus gallicus (3)

Conus gallicus (4)

A1-A6. Kalloconus gallicus (Mayer-Eymar, 1890), Nemeşeşti (Romania), NHMW 2016/0036/0001

 

 

 




 


 

 

Conus gallicus

mm. 35,0 x 17,9

Pliocene – Pietrafitta

[AZFC N. 194-00]

 

Conus gallicus

mm. 21,7 x 11,2

Pietrafitta

[AZFC 194-06]

Conus gallicus

mm. 23,9 x 12,0

Pietrafitta

[AZFC 194-07]

Conus gallicus

mm. 19,4 x 10,1

Pietrafitta

[AZFC 194-12]

 

 

 

 

 

 

 

 



Conus gallicus (4)

NHMW 2016/0036/0001

mm. 50,1 x 31,9

Nemeşeşti (Romania)

Conus gallicus

mm. 35,0 x 17,9

Pliocene – Pietrafitta

[AZFC N. 194-00]

 

Conus gallicus

mm. 23,9 x 12,0

Pietrafitta

[AZFC 194-07]

 

Conus gallicus

mm. 21,7 x 11,2

Pietrafitta

[AZFC 194-06]

Conus gallicus

mm. 19,5 x 11,9

Markhaza

Ungheria

[AZFC 194-01]

Conus gallicus

mm. 19,4 x 10,1

Pietrafitta

[AZFC 194-12]

 

 



Bibliografia Consultata