Szabó János szerk.: Fragmenta Mineralogica Et Palaentologica 23. 2005. (Budapest, 2005)

38 E longitudinally arranged, wide ribs and interposed shallow grooves showing numerous irregularly arranged pores. The borders of the longitudinal ribs are sharp at the lateral sides but indistinct at the sides towards the jugal area (Plate IV: 2). The longitudinal ribs and grooves are parallel to each other and the border of the jugal area but slightly arched towards the mucro at the boundary between the pleural area and the lateral area. The mucro is wide but not prominent. One of the apophyses is missing; the other is large-sized, wide and rounded. The apophyses are probably not connected by jugal plate but the anterior end of the jugal area is straight, without deep sinus mentioned by BALUK (1971). Remarks — SULC (1934) regarded C. denudatus as subspecies of C. corallinus. According to MALATESTA (1962) and BALUK (1971) C. denudatus is the Miocene ancestor of the Recent C. corallinus but later LAGHI (1977) placed C. denudatus into the synonymy of C. corallinus. The studied intermediate valve is similar to C. olivaceus but this latter species has ribbed lateral area, while this part shows only pores at C. corallinus. POPPE & GOTO (1991) mentioned 12-15 strong longitudinal grooves on the pleural areas. The intermediate valve shows 9—9 longitudinal grooves at DELL'ANGELO et al. (1998) while the studied Hungarian specimen has only 7—7 grooves. The outline is different, too: the lateral sides are parallel at DELL'ANGELO et al. (1998) but the outline is trapezoidal at the Hungarian material. Even more significant differences can be observed at the anterior side of the intermediate valve: it is strongly arched and convex at DELL'ANGELO et al. (1998) but nearly straight at the Bánd specimen. LAGHl's (1977) intermediate valve is more similar in outline but its mucro is more prominent and its grooves are not parallel with the sides of the jugal area. MACIOSZCZYK's (1988) intermediate valve (his Plate 3: 2) probably belongs to C. olivaceus, because the lateral area shows some ribs. KROH's (2003) two specimens are much more eroded but both correspond with the Hungarian material. CHIRLI (2004) illustrated two intermediate valves, which are not so wide as the Hungarian one. This species is well known both from the Central Paratethys and the Mediterranean region. C. corallinus belongs to the most frequent chitons both in the Early and Late Badenian deposits of the Central Paratethys (STUDENCKA & STUDENCKI 1988). It was mentioned most frequently from Poland (BALUK 1971, 1984; STUDENCKA & STUDENCKI 1988, MACIOSZCZYK 1988). KROH (2002) have found this species in the Badenian deposits of Gainfarn, while DELL'ANGELO et al. (2005) at the famous Transylvanian locality of Läpugiu. STUDENCKA & STUDENCKI (1988) mentioned this species from the Upper Badenian deposits of Ukraine, too. LAGHI (1984) identified C. corallinus from the Pliocene sands of Siena. BELLOMO & SABELLI (1995) have found several valves in the Pleistocene deposits of Calabria (it was the second most common chiton species of this assemblage) but at the same time SABELLI & TAVIANI (1979) mentioned only one head valve from the Pleistocene of the Stirone river section. Distribution — Miocene: Central Paratethys (Austria, Czech Republic, Poland, Ukraine, Romania, Hungary), Mediterranean Sea (Italy); Pliocene-Pleistocene (Italy). Recent representatives of this species are known throughout the Mediterranean Sea, and it is especially common in the Western Mediterranean. C. corallinus have migrated from the Mediterranean Sea into the Red Sea via the channel Suez (POPPE & GOTO 1991) but according to DELL'ANGELO et al. (1998) the Red Sea record of this species is a misidentified Chiton maldivensis (E. A. SMITH, 1903). Paleoecology — This species can be found on different kinds of hard substrates. It is common on coralline algae between 30 and 100 m depths (POPPE & GOTO 1991). C. corallinus normally was found between 15—100 m, associated with coralligenous habitats by DELL'ANGELO et al. (1998). BELLOMO & SABELLI (1995) indicated this species from infra- and circalittoral zones. According to BALUK (1971) C denudatus (-C corallinus) is one of the most common chitons in the Korytnica clays and the depositional depth of the clays was not more than 10 m. This is the predominant Polyplacophora species in the Badenian sandy deposits of the Holy Cross Mts (STUDENCKA & STUDENCKI 1988). Subgenus Khyssoplax THIELE, 1893 Chiton (Rhyssoplax) olivaceus SPENGLER, 1797 (Plate III: 6-8) 1897: Chiton miocenicus MlCHT. — SACCO, p. 89, pi. 7, figs 8-20. 1934: Chiton bohémiens (ROCHEBRUNE) — SULC, pp. 25-26, pi. 2, figs 48, 50-54. 1962: Chiton (Ch.) olivaceus SPENGLER

— MALATESTA, pp. 161-162, text-fig. 18. 1964: Chiton bohemicus (ROCHEBRUNE) — MARINESCU, pp. 180-181, pi. 2, figs 1-3, pi. 3, fig. 1. 1964: Chiton miocenicus MlCHELOTTl — MARINESCU, pp. 181-182, pi. 3, fig. 2. 1965: Chiton bohemicus (ROCHEBRUNE) — BALUK, pp. 368-369, pl. 1, figs 5-6. 1977: Chiton olivaceus SPENGLER — LAGHI, p. 109, pi. 2, figs 5-8, 13. 1979: Chiton olivaceus SPENGLER — SABELLI & TAVIANI, pl. 1, figs 10-12. 1984: Chiton olivaceus SPENGLER — LAGHI, p. 559, text-fig. la-d. 1984: Chiton miocenicus MlCHELOTTl — FERRERO MORTARA et al., p. 299. 1988: Chiton olivaceus SPENGLER — MACIOSZCZYK, p. 54, pi. 3, figs 4-6. 1988: Chiton corallinus (RlSSO) — MACIOSZCZYK, p. 54, pi. 3, fig. 2. 1991: Chiton olivaceus SPENGLER — POPPE & GOTO, p. 60, pl. 1, figs 7-8. 1999: Chiton (Khyssoplax) olivaceus SPENGLER — DELL'ANGELO et al., pp. 270-272, pi. 4, figs 1-8. 2004: Chiton miocenicus MlCHELOTTl — CHIRLI, pp. 14-15, pi. 5, figs 11-15.