Conus (Varioconus) clavatulus (Orbigny, 1852)

 

 

 

Descrizione e caratteristiche:

 

E’ una conchiglia del Miocene Medio e Superiore,ma in Italia e in Spagna è presente anche nel Pliocene inferiore. Le sue dimensioni possono superare gli 8 cm.; la spira è moderatamente alta e dal profilo convesso. Le singole spire sono alte, convesse e lisce, ad eccezione delle linee di accrescimento. La spalla è decisamente arrotondata. L’ultimo giro è liscio, ma presenta fini ondulazioni spirali alla base. La curva subsuturale è curvata asimmetricamente. Assomiglia al Varioconus noe, che però ha la spira più bassa ed è una specie del Pliocene (Kovacs et al., 2014).

Distribution: France, Belgium, Germany, the Netherlands, Turkey, Italy, Spain, Hungary: Letkés, (?)Budapest: Illés street (5).



Medium to large shell, with a slightly elevated whorl composed of 9-10 whorls, the first ones flat or slightly convex and the last ones somewhat concave. Two to four fine spiral grooves can be seen on the first 3-4 whorls of the teleoconch, which later disappear; On the last 2-3 whorls, a fine subsutural spiral groove can be seen in some specimens. Arc-shaped growth lines appear across the entire surface, ending in the anal sinus. Well-marked suture. The shoulder of the last whorl is rounded with a gentle slope in gerontological individuals and more angular in younger specimens. The last whorl has a straight to slightly convex profile, with the surface marked with curved growth lines and more or less pronounced inclined striations on its anterior part. The aperture is not very wide, subparallel, and somewhat narrower anteriorly. Columellar labrum straight, with a small fold on the wall of the siphonal canal; external labrum slightly arched and somewhat thickened. The siphonal canal is wide and shallow; the anal canal is well marked with an abapical inclination inward. Symmetrical parallel spiral saffron-colored lines are visible across the entire surface of the last whorl (7).

 

 
Conus clavatulus (6)
 54,55 M 60,10101, Costeiu: mm. 71
56,57 M 60,10114, Costeiu: mm. 43

 

 

 

 

 

 
Conus clavatulus
 mm. 48,1 x 26,2
Pliocene (Piacenziano)– San Giminiano
[AZFC N. 403-01]
 
Conus cf. clavatulus
mm. 10,5 x 5,8
Miocene – Aquitaniano
Saint Martin d'Oney
[AZFC N. 264-11]


In attempting to identify this small specimen, I focused primarily on its coloration, which I've never observed in other specimens. I'm not giving up, but now I'll focus primarily on its morphology. I'm currently comparing it to Conus clavatulus, whose description is "The individual whorls are tall, convex, and smooth, except for the growth lines. The shoulder is decidedly rounded. The last whorl is smooth, but has fine spiral undulations at the base.(5)"
The presence of longitudinal zigzag lines does not necessarily mean that this specimen belongs to a different species. Even in living species, longitudinal lines are present in some specimens, while in other specimens of the same species these lines are completely absent.

 

 

 

 
Conus clavatulus (6)
mm. 71
 54,55 M 60,10101
Costeiu (Romania)
Conus clavatulus
 mm. 48,1 x 26,2
Pliocene (Piacenziano)
San Giminiano - Italy
[AZFC N. 403-01]
Conus clavatulus (6)
mm. 43
 56,57 M 60,10114
Costeiu (Romania)
Conus cf. clavatulus
mm. 10,5 x 5,8
Miocene – Aquitaniano
Saint Martin d'Oney
France
[AZFC N. 264-11]



 


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