Szabó János szerk.: Fragmenta Mineralogica Et Palaentologica 26. 2008. (Budapest, 2008)

Sculpture — Whorls ornamented with spiral cords, crossed by club-shaped, more or less periodically repeating ribs from upper suture to angulation of whorls where suddenly terminating with thickest part. Secondary riblets also appear on some specimens. Collabral ornament of threads and cords sometimes produce network with spiral cords. Ridges or riblets may be irregularly present also around umbilicus. Remarks — ). A. ELDHS-DESLONGCHAMPS (1849) established P. debuchii as having four varieties of discoidal to medium high trochospiral forms. D'ORBIGNY (1854) applied new species names instead of varieties, P. Mopsa D'ORBIGNY for "oxyspira" and "' exertiuscula" (higher trochospiral forms), and P. platyspira D'ORBIGNY for var. "platyspira" and "cinguliferd" (almost planispiral forms). STOLICZKA (1861) applied the name "P. Buch" OESE for some shells (Figure 37), two specimens (Figure 38) were also found in the box labelled as "P. Suessi HÖRNES, 1853" (SZABÓ 2008). Further specimens of high morphological variability, but in bad state of preservation, are found also in the "background" collection; some specimens considerably differ from the published "varieties". SZABÓ (1980) identified three specimens as Pleurotomaria cf. platyspira DESLONGCHAMPS, 1849, belonging to a single morphotype. Recendy FISCHER & WEBER (1997) revised D'ORBIGNY's originals; they practically renewed J. A. EUDES-DESLONGCHAAIPS's species interpretation. Their Pleurotomaria (Palantodiscus) debuchii is a single but extremely variable species with "morphes" instead of EUDES-DESLONGCHAMPS's (1849) varieties. Spire height of this species varies from the almost plane (170°) to rather high (85°). At the same time, without explanations, they suggested subgenus status to Talantodiscus P. FISCHER, 1885 within Pleurotomaria. This suggestion might be acceptable, but problematic with the extremely variable species concept of P. (I.) debuchii. Namely, by this species interpretation, two (sub)generic diagnosis would refer to the same species because the trochospiral forms rather well fit to the diagnosis of Pleurotomaria but Talantodiscus would be applicable for the depressed, almost discoidal "morphes". In realty- the taxonomical problem is similar to that of the "foveolatd' species-group: is "debuchii' a single but extremely variable species or more than one species, unsatisfactorily documented in the fossil record therefore unreliably distinguished? In their case, the available documentation is much worse than in the "foveolata" species-group therefore formation of an opinion remains pending. Distribution — Hierlatz Alpe, Sinemurian (Oxynotum Zone); Sümeg (Bakony Mts), Upper(?) Sinemurian; Calvados, (France),Pliensbachian (Margaritatus to Spinatum Zones); Herford (NW Germany), Upper Pliensbachian ? Pleurotomaria princeps (KOCH, 1837) (Figure 39: G-H, K) ? 1837: Trochus princeps KOCH — in: KoCH & DENKER, p. 26, pl. 1, fig. 18. ?pars 1853: Pleurotomaria principalis MÜNSTER — HÖRNES, p. 761. pars 1861 : Pleurotomaria princeps KoCH & DENKER — STOLICZKA, p. 189, pi. 4, figs 7 c, 9. cf. 1997: Pyrgotrochusprinceps (K( )CI l, 1837) — Lisa 1ER & WEBKR, pp. 156, 160, pi. 34: 10 a-b, 11 a-b. Materi a 1 — GBa 2008/69/43/1/1-11 Measurements H HL I 1P GBa 2008/69/43/1/1 - 16 *9 GBa 2008/69/43/1/2 **9.5 **6 Shape — Moderately high conical shell of rather low whorls, separated by impressed-canaliculate suture. Early whorls have cyrtoconoidal outline. Narrow ramp appear on third whorls after nucleus, that remains present on all subsequent whorls but nodes on its abapical edge may make it obscure. Periphery rounded and swollen, corrugated by another row of strong nodes. Outer face oblique and concave with selenizone in its middle line; selenizone itself feebly concave in early juvenile stage then gradually changing into flat, and median thread appears on it, becoming keel-like on last whorls. Base flat or conca\

r

e and broadly phaneromphalous; peristome not preserved in available material. Sculpture — Beside mentioned prominent rows of nodes and keel on selenizone, spiral treads cover whorls and base. On juvenile shell collabral ornament also marked (reticulate sculpture) but on subsequent whorls, it becomes subordinate, only fine growth-lines visible. Both rows of nodes collabrally elongate, sharp and rib-like on juvenile shell but rounded on last whorls. D W AA AL *27 - - *53° **13 52° 57° Remarks — Prochus princeps is an early recognised species. Subsequent authors sometimes forced identification of their specimens with it, therefore its interpretation extended that appears unjustified in some cases. Until a comparison of the Hierlatz finds to type specimen(s), the question mark seems justified before the name. The specimens in STOLICZKA (1861) collection surely do not belong to a single species, nor to the same genus, and, regarding the unique, non-pleurotomariid early shell morphology in Pyrgotrochus? cf. precatoria (J. A. EUDESDESLONGCHAMPS, 1849) (see below), they may belong also to different families. Because the shells, identified under the name ? P. princeps (KOCH, 1837), has a narrow subsutural ramp on full length of the shells and a selenizone in mid-whorl position, the correct genus name is most probably Pleurotomaria; in this case, the shell form is somewhat homeomorphic to that of Pyrgotrochus P. FlSCHLR, 1885. Distribution — Hallstatt, Hierlatz Alpe, Sinemurian (Oxynotum Zone).