Cerithiinae Fleming, 1822

Harzhauser, Mathias, Guzhov, Aleksandr & Landau, Bernard, 2025, A revision of the Cainozoic Cerithiidae and Plesiotrochidae (Mollusca: Caenogastropoda) of the Paratethys Sea (Europe, Asia), Zootaxa 5625 (1), pp. 1-180 : 58

Subfamily Cerithiinae Fleming, 1822

Genus Chondrocerithium Cossmann, 1906

Type species. Cerithium calculosum de Basterot, 1825 , original designation by Cossmann (1906: 82). Early Miocene, France.

Diagnosis. “ Medium to fairly large size; shape usually ventrose, although conical; spire moderately elongated, pointed at the apex, with slightly conoidal outline; protoconch smooth, paucispiral, subglobose, with bulbous nucleus; whorls not very convex, varicose, decorated with spiral rows of granulations or nodosities alternating with smooth threads. Last whorl equal to two fifths of the total height, carrying a very strong varix, opposite the labrum; oval base, not limited at the periphery, decorated with granular cords and threads, extending to under the neck, which is obliquely curved, funiculated and under which the lateral varix forms. Oval-rounded aperture, with a continuous and thickened peristome, bearing a deep furrow limited by a rather protruding parietal rib; canal anteriorly narrowed, rather short, truncated and a little deflected; labrum barely inclined in profile […] carrying two or three strong lirae, especially visible opposite to the penultimate varix.” ( Cossmann 1906: 82, translated from French).

Discussion. Chondrocerithium is characterized by its somewhat irregular shape due to the prominent, bulging varices and by lirae deep in the aperture. Its sculpture consists of numerous spiral cords with more or less prominent tubercles or granules. It lacks any clear mid-whorl cord or angulation as is typical for Thericium .

Stratigraphy. The type species comes from the Early Miocene of France, but the genus has roots in the European Paleogene with species such as the Eocene C. passyi ( Deshayes, 1864) and the Oligocene C. intradentatum ( Deshayes, 1864) . Chondrocerithium gibbosum ( Eichwald, 1830) is the stratigraphically youngest representative of this genus. The placement of the Danian Cerithium pauli Briart & Cornet, 1873 in Chondrocerithium , as proposed by Le Renard & Pacaud (1995) will need verification.

Distribution. The genus is represented by several species in the Northeastern Atlantic from the Eocene to the Early Miocene (Burdigalian) ( Pacaud & Le Renard 1995; Le Renard & Pacaud 1995). In the Proto-Mediterranean Sea, the genus is documented from the Rupelian of Italy, Greece and Iran ( Harzhauser 2004). From the Central Paratethys Sea it is recorded herein for the first time from the late Badenian (Serravallian). The stratigraphically disjunct distribution suggests the presence of so far undetected Middle Miocene species in the Proto-Mediterranean Sea.