Key'oords; Taxonornr-, Gatropods, Naticids, Pliocene, North- crn ItaÌr.-. Riassuttto. Viene descritta e figurate Euspira ntagctto r nuor':r specie di Naticidae rinvenuta in depositi argiiJoso-sabbìosi plioccnici csposti nelle località di R:io Rosello (Emilia, provincia di Piacenza) e Vjllalvernia (Piemonte, pror,ìncie dì Alessandria). L:r specie, di piccola tagììa. e car.rtterizz.rtr d.r sutura canalicolata, ombelico :rbbastenza ampio e profondo, nonché dell'epertura prolungata abapic:rlmente. Si tratta di un elemento poco comunc, probabilmente inlralitorale e leea- to a frcies di transiz-jone trl paleobioccnosì analoghe a queile rrru.ìÌi medìterranee SFBC e DC. Abstract. The nen. n:rtìcic1 specics Euspira magenesz is describecl rnd figurcd. Thc t1-pc-nr:terial u'as recovered fron Plioccne deposits exposcd along the strearr Rìo Rosello (Emilia resjon, Pi;rcenza province) and ncar Villalvernia (Piedmont, Alessandria pror,:ince). The snrall-sizecl Euspira magenesi is featured b1. channeled sLlturej open, rather n-ide umbilicr.rs trnd :bapicrìly prrtlucrd .ìperrure. It is :rn urlcorrìmon infrelittoral element Ìike1v related ro ccorones betu.een palcobiocoenoses sìmihr to the modern Mediterranean SFBC and DC. Introduction In the course of field work aiming to recover narl- cids from the Pliocene outcrops along the stream named Rio Rosello near Sariano (Piacenza province), ren speci- mens of a small polinicine spcc;es were found. The material was obtained from a lenticular body of clayey sand that crops out on the right bank of Rio Rosello, about 280 m south west of Case Badini di Sopra (Fig. t). The calcareous nannofossil contents of the sandy clay resulted to be mostly ren'orked and gave a general Pliocene age (P Maior.rno, wrirren communication, 2000) . According to S. Raffi (oral communicrtion, 2001), this lithotype belongs to the Monte Zago Unit of Piacenzian age as treated by Roveri et al. (1998). An 'l additional specimen was recovered later on in Piedmont, from tr layer of fine sand exposed on the right bank of the stream Rio Vaccaruzza northeast of Villalvernia (Fig. 1). The sandy layer pe rtains to the uppermost p.1rr of the Pliocene formation known as Argille di Lugagnano (Lugagnano Clay) . For further information on this lat- ter loc.ility, reference can be made to Brambilla (1976). The species, that fits in with the characters of the genlrs Euspira Agasúz in J. Sowerby, 1837, after thor- ough examination of literature data and of number of Neogene naticids in the Bellardi-Srcco collection (Uni- versity of Torino), proved to be previously undescribed and is discussed and figured herein. Systematic account The suprageneric rrr.rngemenr is th:rt adopted in recent major revisions of the Family Naticidae (Kilburn 1976;Marrncovìch 1977; Majima 1989). We follow Maji- ma (1989) and Bouchet & Waren (1993) in ranking Euspira Agassiz in J. Sowerby, 1837 as a full genus of the subfarnily Polinicinae. The bulk of the studied material is housed in the Museo G. Cortesi di Castell'Arquato (MGC); paratype 551/GF (unfigured) is stored in the Museo di Ecologia e Storia Naturale di Marano sul Panaro, Modena, paratype 23957 (unfigured; in the Collezione Malacologica of the Museo di Geologia e Paleontologia G. Cappellini, Bologna and paratype MZB 18569 (unfigured; in the Laboratorio di Malacologia, Bologna. Symbols for shell dimensions are: NW number of whorls; PD, diameter of the protoconch; H, height of the shell; D, maximum diameter; ha, height of the aper- ture; MSA, mean spire angle. Rivista Italiana di Paleontologra e Strtrtigrafia UICCNIDTE IUU NOTA BREVE-SHORT NOTE EUSPIRA MAGENESI, A NE\T SPECIES OF THE NATICIDAE (GASTROPODA) FROM THE PLIOCENE OF ITALY LUCA PEDRIALI': & ELIO ROBBA'}'I Recehed July 5, 20Al: accepted Septetnber 21, 2A01 " Vja S. Pertini 29,I11A16 San Martino, Ferrara, Itali,'. 'r': Dipartimento di Scienze Gcologichc e Geotecnologje, Unìr'ersità degìi Studi di Mìlano-Bicocca,Piazzt clella Scienza 4,I2A126 Milano, Italr'. E maìl: elio.robbaCaunimib.it 484 L. Pedriali €' E. Robba Family Naticidae Forbes, 1838 Subfamiiy Polinicinae Finlay Er Marwick, 1937 Genus Euspira Agassiz in J. Sowerby, 1837 The Eocene Natica glaucinoides J. Sowerby, 1812 is the type-species by subsequent designation (Bucquoy, Dautzenberg & Dollfus 1883, p. 1a3). The synonymy of Natica glaucinoìdes with Natica labellata Lamarck, 1804, stated by Cox (1930) and accepted later on by several authors, was rejected by Vrigley (1949) who regarded the two species as distinct and redescribed Sowerby's taxon. According to Kabat (1991), Laguncula Benson, 1.842, Bensonia Gray, 1847, Lunatìa Gray, 1847, Ampul' Lonatica Sacco, 1 890, Labellinacca Cossmann, 1'918, Dal- litesta Mansfield, 1930, Scarlatia Schileyko, 1,977 and Pseuclopolinices Golikov Er Sirenko, 1983 are synonyms of Euspira. Fig. 1 - Location map of the tYPe- locrìir; o[ [usPira mage't,si sp. n. (bottom, right) and of the orLtcrop near Villalvernia (bottom, left). The diagnostic characters o{ Euspira are 1) shell thin to moderately thick, globose or globose-elon gate, 2) protoconch low-turbiniform of r.5-2.5 smooth whorls, 3) sPrre depressed to moderately elevat- ed, somewhat stepped in some species, 4) sutllre we aklY impressed to channeled, 5) umbilicus open rnd deep. nar- row to wide, 6) funicle weak to absenl, 7) parietal callus moder- ately thick, slender, n'ith distinct anlerior lobe slightly overhang- ing the adapical part of the umbilicus, 8) umbilical callus indistinct to rroderately developed, merging into the anterior lobe of the parietal callus or demarcated from it by a weak groove. 9) corneous operculum. Euspira is a distinctive cosmopolitan genus useful to accomodate polinicine species with the open (not slit- like) umbilicus virtually devoid of funicle and with strongly reduced to absent umbilical callus. Six well known species from the Italian Pliocene do belong to Euspira, namely Natica fusca de Blainville, 1825, Lwnatia grossularia Marche-Marchad, 1957, l"latica guillemini Payraudeau, \826, Nerita helicina Brocchi, 1.81.4, Natica macilenta Philippi, 1844 and Natica pulchella Risso, 1826. Sacco (1891) created several varieties oÍ Euspira catena (Da Costa, 1778) that, at least partly, belong here. They will be dealt with in a forthcorning revision o1 Pliocene naticids (Pedriali & Robba, in preparation). f19.1 Fig. 3 PLATE 1 - Euspira magenesi sp. n. Holotype. Rio Rosello. MGC 567; a) apical n'horls arrorv), b) top view, c) protoconch, d) apertural side, e) abapertural side' f) base, ì) umbilical cavitl4 l) and m) sculpture of the umbilical wall - Euspira magenesi sp. n. Paratype. Rio Rosello. MGC 568; apertural side. - Euspira magenesì sp. n. Paratype. Villalvernia, MGC 523; apertural side. (the protoconch-teleoconch transition indic;rtcd by spire, g) detail of the channeled suture (arrow), h) Euspira //tLrga//est 486 L. Pedriali & E. Robba Euspira magenesi sp. n. Pli t, fig. l-3 Derivation of name. The spccìes is nlmcd after Paolo Mirgcnes s'ho provided the type-meteriai. Holotype. Rio Rosello: MGC 562 (P1.1, fie. 1a-m). Paratypes. Rio Rosello: 5 spms., MCC 568-5/2; 1 spm., 551/GF; 1 spm.,23957; 1 spm., MZB 18569; Villalvernia: 1 sprn., MGC 573. Preservation. txcept for minor danages of rhe perisromc ìl some specimens, the preservation is fair. Type-locality. Rieht benk of the srream Rio Rosello, 280 m south west of Case Badìni di Sopra ne:rr rhe village of Sari;rno (Piacen 7,x) . Horizon. Lcns-shaped intercalation oI clavel, send in the Monr,. Z.rgo Unit, Lon cr Pìrienzi.rn. Diagnosis. Depresscd-globose, thin shcll u.ith moderatelv high to depressed, somervlrar stepped spire. Protoconch o[ l.l5-2 smooth s.horls. Sutures channeled. Umbilicus wide and decp, bound- ed bv a sharp :rngulation. Umbilìcal n.all excar-ated, sculpured with spi- ral cords crossed b1. coarsc growth lines. Aperture hrgh, proJuccd abapicallr: Parietal callus with slender anterjor lobe reaching the basal fasciole. Funicle wanting. Umbìlicel callus modcratel). d"""'oO.O, attachcd to the adapical part of the umbilicus and nerging ìnto the anterior lobe of the pariet:rl callus. Description. Shell small, only slightly exceeding Z mm in height, thin, depressed-globose, with moderately elevated, obtuse spire that is about 2A 'k oî the shell height. Protoconch low-turbiniform of 1.75-2 apparent- ly smooth whorls, faintly but distinctly demarcated from the teleoconch because of change in the shell tex- ture; the diameter averages 0.93 mm. Spire somewhat stepped, whorls convex, meering rt deeply and broadly channeled sutures. Body whorl large, somewhar depressed, rather quickly expanding and produced abapically toward the aperture; periphery sliehtly above midÌine. Umbilicus wide and deep exposing earlier whorls, clearly demarcated from base by a sharp enguh- tion; umbilical wall descending steeply ro a narro.w and shallow spiral groove, rhen excavared to form a broad spiral depression sculptured with uneven, low spiral cords brossed by coarse gros/rh markings resulring in xn irreg;ular square-reticulated pattern. Basal fasciole poor- ly differentiated. Aperture ovarely D-shaped, slìghtly obiique, markedly produced abapically, nearly as high as twice its width. Parietal callus thin to moderarely rhick, reaching the basal fasciole; anrerior lobe slender, with pointed edge slightly extending over the adapical part of the umbilicus. Funicle absent. Umbilical callus moder- ately developed, triangular to semicircular, occasionally with faint transverse furrow; it attaches to the ad;rpic.rl part of the umbilicus and merges into the anterior lobe of the parietal callus. Operculum unknown, supposed ro be corneous. Outer surface smooth except for dense, thin grosrth lines that are coarser over rhe basal fasciole; a faint spiral striation is noted on lower base. Nicely pre- served specimens exhibit a yellowish background witl-r fine, distant reddish collabral lines, in some insrances restricted to parr of the body n'horl; surural channel red- dish-brown, with adaxial blackish band. Dimensions (mm): N\l PD H D ha MSA MGC 567 (holotl.pe) 4.00 0.92 1.03 4.05 3.31 1OO" MGC 568 4.25 0.E9 1.31 4.16 3.4r 96" MGC 569 ,t.50 0.95 MGC s70 4.75 8.OO MGC 571 4.00 - 3.58 1.02 2.63 1Os. MGC 572 .t. 10 - 3.65 1.13 3.A7 115" MGC 573 4.75 A.96 7.A5 7.11 6.41 109. Remarks. The present new species fully matches the characters of the genLrs Euspira Agassiz in J. Sower- by, 1837 as summarized above, and shares the most sig- nificant features wrth Euspira glaucinoides (J. Sorverby, 1812). The type-species has markedly globose shell with higher spire, impressed suture and somewhat smaller tumbilicus devoid of inner spiral sculprure. Euspira mtlgenesi is easily distinguished from the others Euspira species in combining 1) somewhat stepped spire,2) channeled sutures, 3) depressed body whorl, 4) rvidely open umbilicus, 5) sculptured umbilical wall and 6) high, abapically produced aperture. The Miocene North European Euspira nysti (d'Orbrgny, 1852) and Euspira gottschei (Kautsky, 1925) are closely related, but have lower and broader, more distinctly D- shaped aperture (cf. Janssen 1984, pl. 55, figs. 4, 5). Euspira fusca (de Blainville, 1825), Euspira grosswlaria (M.irche-Marchad, 1957), Euspira guìllemini (Payraudeau , 1826), Euspira beÌicina (Brocchi, 1814), Euspira macilenta (Philippi, i844) and Euspira pulchella (Risso, 1826), occurring in Pliocene deposits of Italy, attain a larger size, have more globose, more robust shell with higher spire and smaller umbilicus. The channeled suture is clearly developed in the Recent North Atlantic Euspira montagui (Forbes, 1838). This species, also small-sized, differs from Ewspìra mage- nesì rn having more globose shell, larger protoconch (1.2 mm in diameter) with spirally sculprured first whorl, lower and broader aperrure and unsculptured umbilical wall. The spiral sculprure of the umbilical wall occurs rather commonly in species of the polinicinc genus Glossaulax Pilsbry, 1929 (cf. Majima 1989) whereas it is unusual in Euspira. It is noted in Euspira catena (D^ Costa, 1778) and appears to be particularly coarse in Pliocene specimens from Belgiurn. In the norrheasrern Pacific area (cf. Maricovich 1977), the Miocene to Recent Polinices (Euspira) le.raisii (Gould, 1842) and the Pliocene to Recent Polinices (Euspira) draconis (DaII, 1903) exhibit a spirally sculprured umbilical wall. All these species differ lrom Euspira mdgenesi in several respects and none of them has either channeled sutures or an abapically produced aperture. Euspira magenesi is an uncommon taxon so far recovered from Piacenzian deposits of Piedmont and western Emilia regions. The rather fragile shell and the smalì size likely have contributed to the failure to find specimens in the past. Furthe r work n-ray expand the dis- tribution and refinc the stratigraphic range that, on the basis of the present material, appears to be restricted to the Upper Piiocene. It is difficult to infer the paleoecological meaning of Euspira magenesi due to the scanty records. In the type-localitv, it belongs to a fossil association characrer- ized by the abundant occurrence of Circomphalus foli- aceolamelloszs (Dillwyn, 1817) and Callista italica (Defrance, 1818), and interprered (S. Rrffi. oral com- munication, 2001) as an infralittoral ecotone between Pliocene counterparts of the modern Mediterranean biocoenoses SFBC (Biocoenosis of Fine \Vell Sorted Sand) and DC (Biocoenosis of the Coastal Detritic) . The mollusk association at Villalr-ernia comoares more closely to a modern SFBC biocoenosis. Accordingly, Euspira megenesi is likely to be regarded as a tolerant sand-related, infralittoral element that has dwelled in SFBC-influenced Pliocene serrrnss. Acknouledgtnents. This paper has benefìted from critìcal reading bv S. Raffi, Uni- versity of Bologna and from revier.ing b,v A. Varen, Swe dish Nluseurn of Natural Histor1., Stockholm. F. Campanino, Museo di Geologi,r e Paleontolo{Ìia, Llniversitv of Torino, provided àccess ro the Bellardì- Sacco Collection. M. Grìgis, Ninove (Belgium), donated specimens of EusPird cdtena from the Pliocene Lillo Formation of Belgiun-r. G. Della Bella, Monterenzìo, Bologna, ailon ed access to his collccrìon. X4. Mar- iani, Civica Stazione Idrobiologica, Mjlano, essisted u'ith photocopies of some essentiri refcrences. Nannoplancton anall.ses bv P Maìorano, Llnivcrsitv of Bari, are also acknou'ledged. The scanning electron micrographs were made b1.A. Rizzi, Unìr'ersity o{ Milano. The com- puter-assernbled platc w;.Ls prepared by F. Facchini, San Martino, Irer- rara. The research u-as granted bv the Unri.ersrtv of Milano-Bicocca. 487 REFERENCES Bouchet P &'Waren A. (1993) - Revision of the Noertheast Atlantic bath,val and abyssal Mesogastropoú. Boll. Malac., Suppl. 3: 579-81A, Milano. Branrbilla G. (.1976) - I molluschi pliocenici di Villah,ernia (Alessandria). I. Lamellibranchi. Mem. Soc. Ital. Sc. Nat., L[us. Ci.oico St. Nat. Mtlano, 21(3): 82-128, lvl r lxn o. Bucquoy E., Dautzenberg P & Dollfus G. (1833) - Les Mol- lusqr.res Marins du Roussillon. Tome 1. Gastropodes. V of 520 pp., J. B. Baillière & Fils, Paris. Cox L. R. (1930) - The Mollusca of the Hangu Shales. Mem. Geol. Suru. Inclia, PaÌaeont. Indica, 15(8): 129-222, CaI- cu ttx. Janssen A.\( (1984) - Mollusken ujt het Mioceen van 'Winter- sw-ijk-Miste. Een inventarisatie, met beschrijr-ingen en afbeeldingen van alle aangetroffen soorren. V of 451 pp., KNNV Amsterdam. Kabat A. R. (1991) - The classification of the Naticidae (Mol- lusca:Gastropoda): Review and analysis of the supraspe- cific taxa. BulL. Mws. Comp. Zool., ts2(l): 417-449, C:rmbridge. Kilburn R. N. (1926) - A revision of the Naticidae of Southern Africa and MoEambique (Mollusca). Ann. Natal Mus., 22 (3) : 829-884, Pietermaritzburg. Majim:r R. (1989) - Cenozoic Fossil Naticidee (Mollusca:Gas- tropoda) in Japan. Bwll. Amer. Paleont.,96(331): 1-159, Ithaca. Marjncor.'ich L. (1977) - Cenoz-oic Naticidae (NIollusc:r: Gas- tropoda) of the Northeastern Pacific. Bull. Amer. Pale- ont, 7a(.294): 169-491, Itha.cl Ror.eri M., Visentin C., Argani A., Knezaurek G., Lottaroli F., Rossi M., Taviani M. & Vigliott; L. (1998) - The Castel- I'Arquato Basin: sequence srrarigraphy and stratal prt- terns of an uplifting margin in the Apennines foothills (Itaìy). Giorn. Geol., 6a: 323-325, Bologna. Sacco F. (1891) - I Molluschi dei Terreni Terziani del Piemonte e della Lìguria. Parte VIII. Galeodoliidae, Doliidae, Ficulidae e Naticidae. V of 112 pp., C. Clausen, Torino. Wrigley A. (1919) - English Eocene and Oligocene Naticìdae. Proc. MalacoL Soc.,28: 1O-30, London. Euspira magenesi