Thericium dzieduszyckii ( Friedberg, 1914 )

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 : 103-104

Thericium dzieduszyckii ( Friedberg, 1914)

Figs 46A–D

* Cerithium dzieduszyckii Friedb.— Friedberg 1914: 263 , pl. 16, figs 7, 12.

Cerithium Dzieduszyckii Friedb.—Friedberg 1928: 596 .

Cerithium Dzieduszyckii Friedb.— Friedberg 1938a: 94 .

Cerithium dzieduszyckii Friedberg, 1914 — Zelinskaya et al. 1968: 153, pl. 38, fig. 6.

Cerithium dzieduszyckii Friedb.— Urbaniak 1974: 31 , pl. 13, fig. 1.

non Cerithium (Ptychocerithium) aff. dzieduszyckii Friedberg— Švagrovský 1960: 76 , 138, pl. 7, fig. 10.

Type material. Lectotype designated herein, specimen illustrated in Friedberg 1914: pl. 16, fig. 7, SL: 34.7 mm, MD: 14.8 mm, Golubytsya ( Ukraine), late Badenian (Middle Miocene); Friedberg (1914) gave Hołubica (= Golubytsya) as locality in the plate captions but did not mention the locality in his description on page 263. Therefore, the type locality remains unclear. The specimens were probably stored in the State Museum of Natural History of the National Academy of Sciences of Ukraine in Lviv (formerly Muzeum Dzieduszyckich) but not found in that part of Friedberg’s collection and are probably lost.

Illustrated material. PIN 5904/111, SL: 31.2 mm, MD: 12.4 mm, Zaichyky ( Ukraine), Fig. 46A ; PIN 5904/112, SL: 29.3 mm, MD: 13.3 mm, Gryts’kiv ( Ukraine), Fig. 46B ; PIN 5904/113, SL: 43.7 mm, MD: 15.7 mm, Lanivtsi ( Ukraine), Fig. 46C ; PIN 5904/114, SL: 15.4 mm, MD: 6.5 mm, Zaichyky ( Ukraine), Fig. 46D .

Revised description. Large sized, slender shell with orthoconoid spire of about 14 teleoconch whorls, attaining near 60–70 mm in height. Protoconch unknown. Early teleoconch whorls angled below mid-whorl, changing to subcylindrical profile on later whorls. Suture distinctly incised on early teleoconch, shallower on late teleoconch. First teleoconch whorl with two prominent close-set spiral cords placed at and below mid-whorl; adapical one coinciding with angulation. First secondary spiral cord appears on third whorl at adapical suture before start of axial sculpture. Subsequent whorls with prominent axial ribs, separated by slightly wider interspaces. Numerous additional secondary cords intercalated on later whorls. Abapically, axial ribs weaken, alternating with poorly defined varices (about two axial ribs between varices, but separation becomes difficult on late teleoconch). Number of axial ribs increasing with ontogeny from nine on early whorls to 12–14 on middle whorls, 14–15 whorls on penultimate whorl. Later whorls with broad, indistinctly tuberculate subsutural cord (appearing on fifth whorl), shallow concavity below with two smooth cords, followed by faint angulation caused by slightly elevated, weakly tuberculate spiral cord, followed by two smooth spiral bands and slightly more prominent cord with faint tubercles. One or two weaker spiral cords at abapical suture. Last whorl with large varix opposite aperture. Base strongly constricted, with broad peribasal cord, which is partly visible at suture on preceding whorls. Second prominent spiral cord in middle of base accompanied by three to four weaker cords. Aperture poorly preserved. Columella broadly and shallowly excavated. Columellar callus forming thick, broad rim, sharply delimited from base. Siphonal canal moderately long and clearly curved.

Discussion. This species is known only from subadult shells and fragments of adult shells lacking early whorls. It differs from Thericium bursucense sp. nov. in its more prominent, less numerous and wider-spaced axial ribs, with more prominent tubercles and more prominent spiral sculpture on late whorls. We await further material to better characterize this species.

Paleoenvironment. Unknown.

Distribution. An endemic species from the late Badenian (Serravallian) of the Polish-Ukrainian Fore-Carpathian part of the Central Paratethys.

Central Paratethys. Late Badenian (Middle Miocene): Voronyaky Hills: Golubytsya (Lviv Region); Polish-Ukrainian Fore-Carpathian Basin: Tarnów ( Poland) ( Urbaniak 1974); Gryts’kiv, Tarnoruda, Zaichyky (Khmel’nytskyi Region), Fashchivka, Lanivtsi (Ternopil Region, Ukraine) ( Friedberg 1914, 1938a, hoc opus).

Figures

FIGURE 46. Thericium dzieduszyckii (Friedberg, 1918). A. PIN 5904/111, Lanivtsi (Ukraine). B. PIN 5904/112, Zaichyky (Ukraine). C. PIN 5904/113, Gryts’kiv (Ukraine). D. PIN 5904/114, Zaichyky (Ukraine). All Middle Miocene, late Badenian.