Conus exiguus (Eichwald, 1830)

Conus eichwaldi (Harzhauser & Landau, 2016)

 

Conilithes eichwaldi nov. nom. is proposed as new name for Conus exiguus (Eichwald, 1830) [non Lamarck, 1810].

 

 


Descrizione e caratteristiche (1):

 

Syntypes: Two potential syntypes are stored in the Zoological Museum of St. Petersburg (Russia); inventory number ZISP 62085.

 

Type locality. Eichwald (1830) mentioned Bilozirka (= Bialazurka, Bialozurka) and Shushkivtsi (=Shukowze) as type localities but on the label of the available specimens the locality is given as Zalisce. Therefore, it is unclear if these specimens are syntypes. In any case, all localities are located within a small area about 50 km NE of Ternopil (Ukraine).

 

Age: Middle Miocene, Badenian (Langhian or Serravallian).

 

Etymology. Referring to the Russian palaeontologist Karl Eduard von Eichwald (1795–1876), who was a pioneer in geosciences in the Carpathian Foredeep.

 

Description. Small strombiform shells with high spire; teleoconch consisting of at least 9 whorls; spire gradate to scalariform with beaded carina placed mid-whorl or close to the lower suture; sutural ramp faintly striate. Shoulder broadly rounded, weakly subangulate; position of maximum diameter below shoulder; shoulder striate; subsutural flexure unknown. Last whorl stout, concave below maximum diameter, constricted; lower third of last whorl with sharp spiral cords; siphonal fasciole indistinct. Aperture largely missing in both specimens. Shell measurements and ratios. 2 specimens are available: SL: 15 mm, MD: 7 mm, spire angle: 60°, last whorl angle: 33°; SL: 11 mm, MD: 6 mm, spire angle: 70°, last whorl angle: 40°

 

Discussion. This species is unique among Paratethyan cones for its high spire and rounded shoulder, resulting in a strombiform profile. It is reminiscent of Plagioconus burdigalensis (Mayer, 1858), from the Burdigalian of the Aquitaine Basin, which also has a gradate to scalariform spire with carina and a last whorl with a broadly rounded, weakly subangulate shoulder and prominent spiral cords on the base. It differs from C. eichwaldi in its larger size and elongate last whorl. Therefore, it is unlikely that the Polish species is just a juvenile Plagioconus burdigalensis.

The high spire, ventricose last whorl and striate sutural ramp would also fit in Lautoconus but the tuberculate and scalariform spire outline, are rather untypical for this genus (although Lautoconus desidiosus (Adams, 1854) may form a scalariform spire). Therefore, we tentatively place this species in Conilithes. Eichwald (1830) described this small and rare species as Conus exiguus. This name was already preoccupied by the Recent Conus exiguus (Lamarck, 1810) from New Caledonia. Therefore, we propose Conilithes eichwaldi as replacement name.

 

Paleoenvironment. Unknown; other specimens from the localities mentioned by Eichwald (1839, 1853) are typical nearshore taxa.

 

Distribution in Paratethys. Badenian (middle Miocene): Carpathian Foredeep: Zalisce, Bilozirka (= Bialazurka, Bialozurka) and Shushkivtsi (= Shukowze) (Ukraine)

 

 

 



 

Conus eichwaldi (1)

 

B1–B2. Conilithes eichwaldi nov. nom., Zalisce (Ukraine), ZISP 62085.

C1–C2. Conilithes eichwaldi nov. nom., Zalisce (Ukraine), ZISP 62085.

 

 

Conus arntzenii (Martin, 1916)

RGM.784.937 - Java

 

 

 

Conus exiguus (Eichwald, 1830)

Plate IX  - Fig.4

 

 

 

 

 




 

 

 

 

 

 



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