Bollettino della Società Paleontologica Italiana, 48 (1), 2009, 51-57. Modena, 15 maggio 200951

Two new of Rissoina (: Rissoidae) in the Lower of Valle Ceppi (Torino, NW )

Marta ZUNINO & Giulio PAVIA

M. Zunino, Dipartimento di Scienze della Terra, Università degli Studi di Torino, Via 35, I-10125 Torino, Italy; [email protected] G. Pavia, Dipartimento di Scienze della Terra, Università degli Studi di Torino, Via Valperga Caluso 35, I-10125 Torino, Italy; [email protected]

KEY WORDS - Rissoidae, Rissoina, Lower Miocene, Valle Ceppi, Torino Hills, Tertiary Basin.

ABSTRACT - Two new species of Rissoina from the Miocene of Torino Hills, Rissoina (R.) giuntellii and Rissoina (R.) sturanii, are described in this paper. Rissoina (R.) giuntellii n. sp. is frequent in the Lower Miocene deposits of Valle Ceppi and in coeval and more recent layers of Torino Hills; it is characterized by a small shell with convex whorls, the sculpture is composed by prominent axial ribs and cords visible at the base of the last whorl. Rissoina (R.) sturanii n. sp. is only known from the Valle Ceppi section; it is characterized by medium-sized shells with flat whorls and very fine axial and spiral ornamentation. Because of the reduced number of specimens and their state of conservation, scanning electron microscope photographs were used to study shell micro-architecture where possible. Comparison with the coeval Rissoininae known from the deposits of Paratethys, Aquitaine Basin and Loire Basin confirmed the election of Rissoina (R.) giuntellii n. sp. and Rissoina (R.) sturanii n. sp., currently known only in the Miocene deposits of the Tertiary Piedmont Basin.

RIASSUNTO - [Due nuove specie di Rissoina (Gastropoda: Rissoidae) nel Miocene inferiore di Valle Ceppi (Torino, NW Italia)] - Recentemente è stata avviata la revisione delle associazioni a molluschi del Miocene inferiore della Collina di Torino. I livelli fossiliferi presenti nella località di Valle Ceppi hanno restituito un’abbondante associazione a micro-molluschi, in particolare gasteropodi, ancora mai studiata nel dettaglio. In questa prima nota sistematica vengono descritte due nuove specie appartenenti alla famiglia Rissoidae: Rissoina (R.) giuntellii e Rissoina (R.) sturanii. La prima specie è frequente nei depositi di Valle Ceppi ed è stato possibile riconoscerne la presenza anche nei depositi del Miocene medio di altre località fossilifere della Collina di Torino. Al contrario la seconda specie, rappresentata da un numero esiguo di esemplari, è finora stata riconosciuta solo nel Miocene inferiore di Valle Ceppi. Le analisi morfologiche permettono di riconoscere le due specie da altre congeneriche del Bacino Terziario Piemontese, in base ai seguenti caratteri distintivi: Rissoina (R.) giuntellii n. sp. presenta una conchiglia di piccole dimensioni con giri molto convessi e un’ornamentazione composta da spesse coste assiali e ornamentazione spirale limitata alla base dell’ultimo giro; Rissoina (R.) sturanii n. sp. è caratterizzata da giri piatti con un’ornamentazione formata da tenui coste assiali che si intersecano con i sottili cordoni spirali formando piccole celle rettangolari. Le differenze morfologiche evidenziate rispetto ai Rissoininae di altre località del Miocene europeo, come la Paratetide, il Bacino di Aquitania e il Bacino della Loira, hanno confermato la validità dell’istituzione di Rissoina (R.) giuntellii n. sp. e Rissoina (R.) sturanii n. sp. Questi taxa sono al momento conosciuti solo nei depositi miocenici del Bacino Terziario Piemontese.

INTRODUCTION preservation. Nevertheless, since Ponder’s is the only and most complete classification available, it is adopted here. Rissoids are small to minute prosobranchs found in Our task is facilitated by the shell peculiarity of the seas throughout the world. They usually prefer shallow Rissoina d’Orbigny, 1840, whose representatives water and the greatest diversity of species occurs in the from the Lower Miocene of Valle Ceppi are treated in lowest intertidal and in shallow sublittoral zone where this paper. Taxa assigned to Rissoina show relative large algae, stones, corals or other objects provide shelter. The and turret-like shells, D-shaped apertures usually with oldest fossil rissoids are recorded from the European varix on the outer lip and with anterior and posterior Middle ; few taxa are cited from , channels; furthermore, the protoconch is pauci- to whereas most records pertain to the Cainozoic, especially multispiral, dome shaped, smooth or weakly sculptured. of Europe, Indonesia, Japan, Australia, and New Zealand The of European Mio-Pliocene Rissoina (Ponder, 1984). dates back to the classic monographs on Tertiary molluscs Taxonomic definitions within the family Rissoidae are by Sacco (1895), Friedberg (1911-1928), Cossmann & complicated by the small size of shells and by their Peyrot (1919). Recent contributions with short homoeomorphism due to convergence in architecture and descriptions of some Rissoina include those of Glibert ornamentation, which are often repeated in different (1949, 1962), Kojumdgieva & Strachimirov (1960), subfamilies and genera. The supraspecific classification Baluk (1975; 2006), Landau et al. (2004) and Chirli of Rissoidae was revised by Ponder (1984) and was based (2006). The literature records 27 species from the Euro- on a combination of diagnostic characters found in adult Mediterranean Miocene. Five of these are listed by Sacco shells, embryonic whorls, radula, organic operculum and (1895) from the Lower Miocene deposits of the Tertiary the internal anatomy of living specimens. In fact, such a Piedmont Basin (TPB): Rissoina (R.) pusilla, R. (R.) classification hardly applies to fossil rissoids, at any decussata, R. (R.) obsoleta, R. (R.) moravica, Rissoina systematic level, due to the loss of anatomic and organic (Rissolina) lamellosa. In the Lower Miocene deposits elements and because of the influence of shell of Valle Ceppi, just three of these species were

ISSN 0375-7633 52 Bollettino della Società Paleontologica Italiana, 48 (1), 2009

Fig. 1 - a) Structural sketch map of northwestern Italy (modified after Clari et al., 1994). b) Location of scheme c. c) Schematic map of the sedimentary succession of Torino Hills; dotted areas indicate conglomeratic bodies. recognized (R. pusilla, R. decussata and R. lamellosa); to Miocene molasse-type succession (Festa et al., in in addition, within the examined material, we identified press a, b) and are attributed to the Early Miocene, in two new taxa that are the object of the present paper. particular to the Burdigalian Biozone N7a (Zunino, Only the new species are described here in detail, 2007). Lithologically, the Termofourà Fm. is composed whereas those already described in the literature are by marls, fine to coarse sandstones and conglomerates discussed for comparative purposes. with structures and textures testifying gravity deposition on the outer slope of large submerged fan deltas (Clari et al., 1994). GEOLOGICAL AND PALEONTOLOGICAL DATA The invertebrate assemblages of Valle Ceppi are dominated by molluscs (Zunino, 2007) and gastropods Valle Ceppi is a deep valley cut by the Rio Civera and are the best represented fossils. Common taxa belong to located 3 km northeast of the village of on ( catena, josephinia), the southern slope of the so-called “Colli Torinesi” (Torino Nassariidae (Nassarius badensis, N. tessellatus), Hills; Fig. 1). In its middle part, just upstream of Tetti Olividae (Oliva cylindracea, Ancilla glandiformis), Civera, a set of fossiliferous beds crops out. They match Conidae (Conus antiquus, C. brocchii), Turridae one of the best known localities described by Sacco (1889- (Gemmula subcoronata, Bathythoma cataphracta). The 1890) in the Miocene deposits of the Torino Hills, which microgastropods are nearly unknown: the commonest attracted the interest of many palaeontologists since the groups are Rissoidae (several species of Alvania, beginning of the nineteenth century (e.g. Borson, 1820- Rissoina decussata, R. pusilla), Diastomidae 1825). These include Bellardi (1872-1890) and Sacco (Sanbergeria perpusilla), Litiopidae (Alaba costellata), (1890-1904), whose studies on mollusc assemblages led Cerithiidae (Bittium reticulatum). to the compilation of the namesake collection, formerly The state of shell preservation is good but traces of held at the “Museo di Geologia e Paleontologia” of the erosion and fractures are common on the teleoconch, and Torino University and now transferred to the “Museo are present as a rule on the protoconch. Fossils are totally Regionale di Scienze Naturali di Torino”. allochthonous: the gravity processes that led to the The Torino Hills are a structural domain of TPB that deposition of the fossiliferous beds involved different rises south of the city of Torino and the Po River (Polino biocoenoses, resulting in a mixing of specimens et al., 1991). The fossiliferous layers of Valle Ceppi transported from different environments, ranging from pertain to the Termofourà Formation, within the Eocene the littoral to the epibathyal zones. M. Zunino, G. Pavia - New species of Rissoina in the Lower Miocene 53

MATERIAL AND METHODS Topotypes - Zunino’s collection: 66 specimens (PU108598-PU108664), Giuntelli’s collection: 37 Molluscs from the Burdigalian of Valle Ceppi derive specimens (PU108665-PU108702). from six large samples (weight: 2-5 kg) taken from four different fossiliferous layers, which have delivered homologous assemblages (Zunino, 2007). The specimens of Rissoina described in this paper were extracted from sediment after washing, fractioning with sieves and picking out all the mollusc components. Rissoid shells were mounted on stubs, coated with gold and observed using a “Cambridge S-360°” scanning electron microscope. Morphological features of the protoconch and teleoconch were examined with special attention to shape, sculpture, size and number of whorls. The whorls of protoconch were counted following Jablonki & Lutz (1980: fide Silva, 2001) Comparative material derives from the “Bellardi & Sacco” collection, which assembles the original specimens (Bellardi, 1872-1890; Sacco, 1890-1904) including types, figured specimens and supplementary specimens (Ferrero Mortara et al., 1981, 1984; Merlino, 2007). Additional material was furnished by Piero Giuntelli; his collection includes several specimens of Rissoina sampled at Valle Ceppi, as well as some others sites of the TPB Middle and Upper Miocene such as the Langhian site of Albugnano and the Tortonian to lowermost Messinian sites of Sant’Agata Fossili and Borelli (Ghibaudo et al., 1985; Pavia, 1991; Festa et al., in press b). Besides those held in the “Bellardi & Sacco” collection, all specimens here mentioned are held at the Geo-palaeontological Museum of the Torino University. They are inventoried with codes composed by the acronym PU (Paleontologia Università) and a progressive number according to the scheme proposed by Pavia & Pavia (2005).

SYSTEMATIC PALAEONTOLOGY

Class GASTROPODA Subclass PROSOBRANCHIA Order Cox, 1959 Suborder MESOGASTROPODA Thiele, 1929 Superfamily RISSOACEA Gray, 1847 Family RISSOIDAE Gray, 1847 Subfamily RISSOININAE Stimpson, 1865

Genus Rissoina d’Orbigny, 1840

Rissoina (Rissoina) giuntellii n. sp. Figs. 2 a-f; Pl. 1, figs. 1-2

Derivation of the name - Dedicated to Piero Giuntelli, expert collector of Miocene fossils.

Type horizon and locality - Valle Ceppi (Pino Torinese), Piedmont, Lower Miocene. Fig. 2 - Rissoina (R.) giuntellii n. sp. at scanning electron microscope, upper Burdigalian, Valle Ceppi. a) Holotype PU108591. Type material - Holotype (PU108591); 6 paratypes b) Paratype PU108593. c) Paratype PU108592. d) Particular of shell ornamentation of paratype PU108592. e) Paratype PU108594, (PU108592-PU108597). particular of protoconch, oblique view. f) Paratype PU108595, particular of protoconch, apical view. 54 Bollettino della Società Paleontologica Italiana, 48 (1), 2009

Additional material - 31 from Albugnano Discussion - The architecture and morphology of (PU108703-PU108734), 1 from Bocca d’Asino Rissoina (R.) giuntellii n. sp. are easily distinguishable (PU108735), 3 from Borelli (PU108736-PU108756). from those of other species that occur in the terrigenous deposits of the Miocene Piedmont Basin, in particular: Dimensions - Holotype: H: 3.52 mm; L: 1.4 mm. Rissoina (R.) pusilla (Brocchi): this is the most common species in the Miocene deposits of the Torino Diagnosis - Small shell with convex whorls separated Hills and is recorded in the European Miocene-Pliocene by crenulate sutures; sculpture composed by prominent assemblages (Korytnica Basin, Badenian; Bulgaria, axial ribs, very fine spiral grooving between inner-rib Tortonian; Pliocene of North Italy, Spain, Portugal and spaces and prominent cords visible at the base of the last France). Compared to Rissoina (R.) giuntellii n. sp., the whorl; multispiral protoconch with small nucleus. teleoconch of Rissoina (R.) pusilla is larger and composed of six less-convex whorls; the last whorl Description - Shell small, solid, conic-turret-like. The displays an evenly rounded profile. Ornamentation is protoconch consists of 3-3.5 smooth and convex whorls, similar in both species; nevertheless Rissoina (R.) pusilla diameter 360-370 µm, with a small nucleus, diameter shows 20-33 axial ribs, sharp in cross section, and thin 50-56 µm. The teleoconch has five convex whorls with spiral cords at the base of the last whorl; the aperture is deeply impressed sutures. The last whorl, approximately wider (Pl. 1, figs. 3a-b). a half of the height of entire shell, is strongly convex Rissoina (R.) moravica (Hörnes): the specimens and roundly angled at the base. Ornaments include many described by Sacco (1895) fit sufficiently with the prominent, sharp, straight or slightly opisthocline axial Paratethyan taxon Rissoina (R.) moravica (Hörnes). This ribs, which on the last whorl do not reach the abapical species differs from Rissoina (R.) giuntellii n. sp. in the edge. They number 12 to 16 on the first whorl of the flat profile of whorls and in the axial ornamentation teleoconch, and 18 to 21 on the last one. In addition, reduced to large and depressed ribs limited to the first thin, thread-like spiral grooves, best visible on an SEM whorls of the shell. Moreover, Rissoina moravica has a microscope, are present in inner-rib spaces. Twelve to wide, D-shaped aperture (Pl. 1, fig. 4). The absence of 19 prominent cords are visible at the base of the last protoconch on any specimen of Rissoina moravica from whorl. The apertures narrow, oval to D-shaped, obliquely Torino Hills hinders complementary comparison. oriented and contracted in a narrow anal sinus and distinct With regards to taxa described by Zilch (1934) and siphonal furrow. The absence of varix clearly results Baluk (1975, 2006) from the Paratethys Middle from transport of specimens before fossilization. Miocene, Rissoina (R.) giuntellii n. sp. is similar to Rissoina extranea (Eichwald) and Rissoina eleonorae Remarks - The large number of specimens allow us Boettger in the shape of axial ribs, whereas it differs in to describe variability in Rissoina (R.) giuntellii n. sp. the more convex whorls and the smaller size of aperture. Intraspecific variability consists mainly in the convexity As far as the French Miocene specimens described of whorls and in the number and thickness of axial ribs by Cossmann & Peyrot (1919) and Glibert (1949; 1962) and spiral cords; this is clear in Valle Ceppi samples as are concerned, only Rissoina (R.) exdecussata Sacco is well as in those coming from Middle and Upper Miocene similar to Rissoina (R.) giuntellii n. sp. in the general localities of Torino Hills. In particular, the early shape of teleoconch however Rissoina (R.) exdecussata teleoconch whorls are flat to rather convex, whereas the shows larger axial ribs and spiral cords. The lack of last whorl is usually strongly globular with a roundly taxonomic revisions of small taxa coming from Miocene angular abapical edge. Axial ribs vary in number, spacing France Basin does not permit extensive comparisons. and inclination: they may be straight but they can also be clearly opisthocline. Spiral cords at the base of the last Stratigraphic distribution - Currently, the taxon is whorl may be prominent to weak. known only from the TPB Miocene. More specifically,

EXPLANATION OF PLATE 1

figs. 1-2 - Rissoina (R.) giuntellii n. sp., Lower Miocene (upper Burdigalian) of Valle Ceppi. 1 - Specimen PU108596. 2 - Specimen PU108597. fig. 3 - Rissoina (R.) pusilla (Brocchi). Giuntelli’s Collection, Middle Miocene (Langhian) of Albugnano (PU108598). fig. 4 - Rissoina (R.) moravica (Hörnes). Bellardi & Sacco Collection, Miocene of Sciolze (BS.053.030.006). fig. 5a, b - Rissoina (R.) decussata (Montagu). Lower Miocene (upper Burdigalian), Valle Ceppi (PU108599). fig. 6 - Rissoina (R.) obsoleta (Partsch). Bellardi & Sacco Collection, Miocene of Torino Hills (BS.053.030.005). figs. 7-9 - Rissoina (R.) sturanii n. sp. Lower Miocene (upper Burdigalian), Valle Ceppi (PU108765). 7 - Holotype (PU108765). 8 - Paratype (PU108762). 9 - Paratype (PU108757). M. Zunino, G. Pavia - New species of Rissoina in the Lower Miocene Pl.55 1 56 Bollettino della Società Paleontologica Italiana, 48 (1), 2009 it has been collected in the Burdigalian of Valle Ceppi, Rissoina (R.) obsoleta; it can however be distinguished Langhian of Albugnano, Tortonian of Bocca d’Asino and from both on the basis of the following features: S. Agata Fossili, lowest Messinian of Borelli. Rissoina (R.) decussata (Montagu): this species differs from Rissoina (R.) sturanii n. sp. in the general shape of the shell, i.e. larger size, flatter whorl profile Rissoina (Rissoina) sturanii n. sp. and in ornaments. Axial ribs are thinner and denser mainly Pl. 1, figs. 7-9 in the last whorl; spiral ornamentation similarly consists of numerous and irregular cords clearly recognizable Derivation of the name - Dedicated to the late within ribs, more evident at the base of the last whorl (Pl. Professor Carlo Sturani, the paleontologist from Torino 1, figs. 5 a-b). University who first contributed to modern knowledge Rissoina (R.) obsoleta (Partsch): though similar in of the Miocene stratigraphy of Torino Hills. the shape of whorls, this taxon differs from Rissoina (R.) sturanii n. sp. in the less “conical” profile of the last Type horizon and locality - Valle Ceppi (Pino whorl. Moreover the ornamentation consists of spiral Torinese), Piedmont, Lower Miocene. cords that are further coupled with a narrow spiral groove, whereas axial ribs are weak, strongly opisthocline and Type material - Holotype (PU108765); 2 paratype evanescent near the adapical suture. Also, the sculpture (PU108757-PU108762). is more reticulate with pits formed between sculptural elements and a larger aperture. (Pl. 1, fig. 6). Topotypes - Zunino’s collection: 4 specimens With regards to Miocene species of Rissoina from (PU108758-PU108761). Giuntelli’s collection: 1 Paratethys, the morphology of Rissoina (R.) sturanii n. specimen (PU108763). sp. recalls some taxa recorded from the Middle Miocene of Korytnica by Baluk (1975; 2006) and Kostej by Zilch Dimensions - Holotype: H: 3.99 mm; L. 1.70 mm. (1934), and particularly, in terms of ornamentation, Rissoina (R.) varicosa Boettger and Rissoina (R.) Diagnosis - Medium-sized shell with flat whorls sororcula Boettger. Nevertheless, both species show separated by straight sutures; reticulate sculpture narrower apertures and more convex whorls. composed of thin axial ribs and spiral cords irregular in Furthermore, Rissoina (R.) varicosa is larger and shows spacing and dimension; median-spiral protoconch with varix on the shell surface. small nucleus. Another species similar to Rissoina (R.) sturanii n. sp. is Rissoina (R.) loueli Deshayes, from the Middle Description - Shell medium-sized, solid, turret-like Miocene of Paratethys and from the Lower Miocene of with an elongated spire. The protoconch is conical with Aquitaine Basin (Cossmann & Peyrot, 1919) and the 2-2.5 convex and smooth whorls, diameter 415 µm, Loire Basin (Glibert, 1962); Deshayes’ taxon has similar and small nucleus, diameter 80 µm. The teleoconch ornamentation but strongly differs in the less convex consists of four or five nearly flat whorls, separated whorls, and in aperture size. by straight and impressed sutures. The last whorl, about In comparison with Rissoina (R.) giuntellii n. sp., half of the total height, is slightly convex and roundly Rissoina (R.) sturanii n. sp. is bigger and shows a flatter angled at the base. The axial sculpture consists of thin, whorl profile. Actually, the main differences between the close-set, rounded and curved ribs. Ribs are irregularly two species lie in ornaments: Rissoina (R.) sturanii has spaced, usually becoming more frequent at the last weak ornamentation with thin axial ribs and spiral cords; whorl; they number 12 to 16 on the first whorls, to 47 Rissoina (R.) giuntellii shows predominance of axial to 52 on the last one. In addition, thin spiral cords run ribbing whereas spiral ornaments consist of narrows over the surface of the shell. In the early whorls spiral grooves in the inner-rib spaces, which appear thicker at cords are visible under great magnification between the base of the last whorl. The aperture is similar in the axial ribs; they become stronger in the last whorl, wide two species: oval and narrow. as axial ribs, and outline a reticulate sculpture. The aperture is oval, elongated and posterior contracted; Stratigraphic distribution - As the supplementary both lips are thin. Only one specimen shows an outer material of the Piedmont Tertiary Basin has shown, the varix. species is presently known only from the Burdigalian deposits of Valle Ceppi. Remarks - The specimens from Valle Ceppi are too few to assess variability in this species; morphological features are homogeneous for the whorl profile as well CONCLUDING REMARKS as for the number, shape and dimension of ribs and spiral cords. The recent revision of the Miocene molluscs from the Torino Hills (Zunino, 2007) has highlighted the Discussion - Rissoina (R.) sturanii n. sp. has existence of numerous undescribed taxa, especially small morphological features that could be confused with those gastropods, which will be dealt with in future systematic of coeval species described by Sacco (1895) and Ferrero notes. Mortara et al. (1984) in the Lower Miocene fossiliferous With regards to the genus Rissoina, fossils from the beds of the Torino Hills. In particular the new species is Torino Hills Lower Miocene exceptionally preserve the in some ways similar to Rissoina (R.) decussata and protoconch and literature does not supply any detailed M. Zunino, G. Pavia - New species of Rissoina in the Lower Miocene 57 study on this morphologic argument. On the other hand, Ferrero Mortara E., Montefameglio L., Novelli M., Opesso G., as far as we know the protoconch of Rissoina is very Pavia G. & Tampieri R. (1984). Catalogo dei tipi e degli simple, being paucispiral or multispiral, and composed esemplari figurati della collezione Bellardi e Sacco. Parte II. Cataloghi Museo Regionale di Scienze Naturali di Torino, 7: by almost smooth whorls. We do not expect any definite 484 pp. answers from larval shell morphology, i.e. the characters Festa A., Boano P., Irace A, Lucchesi S., Forno M.G., Dela Pierre of the teleoconch seem to be sufficient to distinguish F., Fioraso G. & Piana F. (in press a). Carta Geologica d’Italia taxa and thus to propose new species. alla scala 1:50000. Foglio 156 Torino Est. APAT, Dipartimento Rissoina (R.) giuntellii n. sp. and Rissoina (R.) sturanii Difesa del Suolo. n. sp. seem to be endemic to the Torino Hills, at least on Festa A., Dela Pierre F., Piana F., Fioraso G., Lucchesi S., Boano P. &. Forno M.G. (in press b). Note Illustrative alla Carta Geologica the basis of the published and figured specimens from d’Italia alla scala 1:50000. Foglio 156 Torino Est. APAT, other classic European sites, particularly those of Dipartimento Difesa del Suolo, 138 pp. Aquitaine and Loire Basins, which pertain to the other Friedberg W. (1911-1928). miocaenica Poloniae, pars I species discussed in this paper. In this respect, special Gastropoda e Scaphopoda. Muzeum Imienia Dzieduszyckich, attention should be devoted to mollusc assemblages of Krakow, 270 pp. Paratethys Middle Miocene (Badenian), in particular to Ghibaudo G., Clari P.A. & Perello M. (1985). Litostratigrafia, those from Vienna Basin, whose expected revision could sedimentologia ed evoluzione tettonico-sedimentaria dei depositi miocenici del margine sud-orientale del Bacino Terziario Ligure- confirm their affinity with Mediterranean taxa, as already Piemontese (Valli Borbera, Scrivia e Lemme). Bollettino della pointed out by several authors (e.g. Pavia, 1991; Zunino, Società Geologica Italiana, 104: 349-397. 2007) Glibert M. (1949). Gastropodes du Miocéne moyen du bassin de la Loire, 1. Mémoire de l’Institut Royal des Sciences Naturelles de Belgique, 30: 240 pp. ACKNOWLEDGEMENTS Glibert M. (1962). Les Mesogastropoda fossiles du Cénozoïque étranger. Première partie: Cyclophoridae à Stiliferidae (inclus). Mémoires de l’Institut Royal des Sciences Naturelles de Belgique, We are grateful to Piero Giuntelli (Nole Canavese), who provided (série 2), 305 pp. the specimens analyzed in this paper, and to Daniele Ormezzano Kojumdgieva E. & Strachimirov B. (1960). Les fossiles de Bulgarie. (Torino) for facilitating access to “Bellardi & Sacco” collection. We VII. Tortonien. Académie des Sciences de Bulgarie, Sofia, 317 pp. would also like to thank Simona Cavagna (Torino) for assistance Landau B., Marquet R. & Grigis M. (2004). The early Pliocene with SEM. Gastropoda (Mollusca) of Estrapona, Southern Spain. Part 2: We are indebted to the reviewers Elio Robba (Milano) and Orthogastropoda, Neotenioglossa. Palaeontos, 4: 1-108. Bernard Landau (Albufeira, Portugal) whose comments significantly Marques da Silva C. (2001). Gastrópodes Pliocénicos Marinhos de improved the paper. Ottavio Janni improved the English of the Portugal. PhD thesis, Lisboa University, 747 pp. manuscript. Merlino B. (2007). Catalogo dei tipi e degli esemplari figurati della The research was financially supported by 2007 funds of the collezione Bellardi e Sacco. Parte III. Cataloghi Museo Regionale Torino University (PG6020007), resp. G. 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