Tectus hungaricus ( Csepreghy-Meznerics, 1952 )

Tectus hungaricus ( Csepreghy-Meznerics, 1952)

Figs 69A View FIGURE 69 1 –A View FIGURE 1 2 View FIGURE 2

* Trochocerithium hungaricum n. sp. — Csepreghy-Meznerics 1952: 227, pl. 14, figs 1–2, 5, 7, 8, 11.

Trochocerithium hungaricum Csepreghy-Meznerics — Strausz 1962: 48, pl. 10, figs 5, 8, text fig. 61.

Trochocerithium hungaricum Csepreghy-Meznerics, 1952 — Strausz 1966: 140, pl. 10, figs 5, 8, text fig. 64.

Trochocerithium hungaricum Csepreghy-Meznerics, 1952 — Pálfy et al. 2008: 110.

Type material. Holotype, M.61.4300, SL: 16 mm, MD: 12 mm, Hungarian Natural History Museum , Budapest ( Hungary), Szob ( Hungary), Middle Miocene, Badenian, illustrated in Csepreghy-Meznerics (1952: 227, pl. 14, figs 1–2, 5, 7, 8, 11).

Discussion. Csepreghy-Meznerics (1952) placed this species in Trochocerithium Sacco, 1896 (type species Trochus turritus Bellardi & Michelotti, 1840 , original designation by Sacco 1896: 90, Early Miocene, Italy). The holotype of ‘ Trochocerithium ’ hungaricum Csepreghy-Meznerics, 1952 is a small, conical shell with relatively low whorls, with a marked swelling along the basal angulation with prominent and wide spaced tubercles, causing a strongly undulating suture. In addition, the slightly concave whorls bear blunt, opisthocline axial ribs. The aperture is subquadratic and the columella has a weak fold. These features place this species in the trochid genus Tectus Montfort, 1810 . Especially, the extant Tectus dentatus ( Forsskål, 1775) and Tectus fenestratus ( Gmelin, 1791) are strikingly similar. Trochocerithium turritum has a linear suture, lacks axial sculpture and bears small beads on the spiral cord at the abapical suture (see https://science.mnhn.fr/institution/mnhn/collection/f/item/j05297).

Houbrick (1990: 238) treated Trochocerithium as junior synonym of Plesiotrochus but we prefer to consider it as distinct genus, based on the large size, the trochiform outline and the flat base of Trochocerithium turritum .