A new species of the genus Lithophyllum (Lithophyllum ippolitoi) was discovered in the Oligocene section of Toleto (Molare Formation, Tertiary Piedmont Basin). The holotype overgrows a coral colony, and is characterised by morphological features and dimensions of cells that are clearly different from those of the other recorded species of Lithophyllum

GRAZIA VANNUCCI

MICHELE PIAZZA

PATRIZIA FRAVEGA

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<em>LITHOPHYLLUM IPPOLITOI</em>. A NEW SPECIES OF CORALLINE ALGAE FROM TERTIARY PIEDMONT BASIN

FRAVEGA, PATRIZIA

PIAZZA, MICHELE

VANNUCCI, GRAZIA

Riviste UNIMI

Riv. It. Paleont. Strat. ., gq n. I pp. 271 276 Í v. t-z Ottobre 1993LITHOPHYLLUM IPPOLITOI. A NE\T SPECIES OF CORALLINE ALGAEFROM TERTIARY PIEDMONT BASINPATRIZIA FRAVEGA*. MICHELE PIAZZA** & GRAZIA VANNUCCI{.Key-uords: Systemetic palaeobotany, Corallinaceae, Lithoplryllam, Oligocene, Tertiary Piedmont Basin.Riassanto. Viene descritta una nuova specie di Rhodophyceae calcaree della Formazione di Molare delBacino Terziario del Piemonte, di età oligocenica. Si tratta di una specie di Litbopbyllum (Lp. ippolito), che èrisultata presente, oltre che nella località di rinvenimento dell'olotipo, anche in un altro settore del Bacino.Abstract. A new species of the genus Litbophyllum (Litbophyllum ippolitol was discovered in the Oligo-cene section of Toleto (Molare Formation, Tertiary Piedmont Basin). The holotype overgrows a coralcolony, and is characterised by morphological features and dimensions of cells that are clearly different fromthose of the other recorded species of Litbopbyllam.lntroduction.The Ph. D. Thesis research work developed by one of the authors (M.P.) in theTertiary Piedmont Basin (N\l Italy) supplied some algal remains with peculiar mor-phological and structural features; new data achieved by focused studies allow to iden-tify a new species.The finding of the same species in a late Oligocene stratigraphic section of theareas of the Tertiary Piedmont Basin corroborates the formalization. The studiesthis section are in progress.The holotype comes from the "e" level (see in Piazza, 1989) of Toleto Section(Molare Formation, SE of Ponzone, Alessandria, S Piedmont, N\f Italy). This section,10 m thick, is formed by breccias, conglomerates, sandstones, and reef limestones(mostly framestones). Lithostratigraphic evidences and comparisons indicate a midlateOligocene age for this section.- \fork supported by research funds from MURST 60yo.'r Dipartimento di Scienze della Terra dell'Universià di Genova, Corso Europa 26, 76732 Genova,Italy - tel. 070-3538262, fax 070-352769."'t Dipartimento di Scienze della Terra dell'Università degli Studi di Milano, via Mangiagalli 34,20733Milano, Italy.S\íon272 P. Fravega, M. Piazza & G. VannucciSystematic descriptionsGenus Lithophyllum Philippi, 1S37Lithophyllum ippolitoi sp. n.Pl. 1, fig. 7-3; PI. 2, tig. 1-37989 Litbopbyllum sp. 2 Prazza, p. 177.Derivatio nominis. The species is dedicated to Prof. Felice Ippolito famous Italian Scientist, whoimproved Earth Sciences in Italy.Holotype. Coll. Toleto, slide 6V.lsotypes. Coll. Toleto, slides 6V; 6Va.Type locality. The holotype comes from the "livello e" of the Toleto Section (Molare Formation).This level outcrops North of the small village of Toleto: elevation 640 m a.s.l., longitude E 3"56'57" andIatitude N 44"34'76". It occurs in reeflimestone and overgrows a coral colony.Description. Crustose thallus (440-900 p thíck and up to 4 cm long).Hypothallus. \fell-developed hypothallus (1oo-2oO p in thickness) vrith cellsmeasuring (L x H) 10-20 (22) p x 5-10 p (mean value 17 lt x 8 lt, number of measures: 30), usually arranged in layers and rarely in irregular rows. The dimensionalcharacter of perithallial and hypothallial cells (L= iength, H: height, D: diameter)are used according to \Toelkerling, 1988.Perithallus. The perithallus (:+o-zoo p thick) is homogeneous and close-pocked,and shows light growth zones. Rectangular cells are arranged in rows turning to grat-ing, and measure (L x D) (8) 10-1s px5-1op (mean value 13 Fx7lt, number ofmeasures : 50).Reproductive organs. Large, elongate, single-pored conceptacles, 3ZO-1OOO pt ininside diameter and 100-200 p in inside height (mean value 580 p x 154 p, number ofmeasure : 20). The chambers usually show concave top, convex bottom with stockyprotuberances measuring 30-70 p in diameter and 30-50 p in height. The triangularsingle-pores are long, and range from 40-60p in basal width and may attain up to 150p high.Comparisons. As the morphological and structural features of our specimens re-semble Lithoplryllum umbilicatum Mastrorilli, 1968 (p. 362, pI. 36, fíg. t, z), LithopbyL-Ium perrandol Airoldi, 1932 (p.71, pl.10, fig. 7; pl. 11, fig. t), Litbophyllum ligusticumAiroldi, 1932 (p. 72, pl. 77, fig. 2, 3), Lithoplryllum sassellense Fravega & Vannucci, 1980(p. 34, pl. t, fig. 1, 2), we compare it with these forms.Litbophyllum umbilicatum resembles the new species by the similar shape of con-ceptacles, but it differs by the arrangement of hypothallial cells (mostly in rows) andperithallial cells (mostly in layers). Perithallial cells have also smaller maximum length(L: e-12 p).Litb ophyllu m perrand oi, Lith opbyllu m ligusticu m, and Litb ophyl lum sassell ens e r e-semble the new species only by thallus growth morphology, hypothallial cells arrange-ment, and conceptacle dimensions, but they differ by every other morphological anddimensional character.Lirhopbyllum ippoliroi E. n. l/ )Remarks. The level ("livello e") which the new species comes from, consists of1.5 m of framestones with lenticular bodies of coarse, grain-supported sandstone. Sand-stones show sparry calcite cement (rarely lime mud matrix in smaller areas) and verylow porosity. Coarse and well-rounded grains of serpentinite, calcschist, quartzite,qtJartz, mica, Fe-oxide, pyrite, and spheroidal aggregates of microcrystailine glauconiteform the abundant silicoclastic skeletal fraction. Coral and serpulid fragments, bryo-zoans, foraminifers, and coralline algae thalli are present as bioclastic skeletal fraction.Miliolids, textulariids, and rotaliids are the most abundant forms of foraminifers.The algal assemblage of the sandstone bodies includes (Pìazza, 1989):"Lithothamnium" undulatum Capeder,ISOO; "Lithothamnium" cf . exuberans Mastrorilli,1968; Mesophyllum cf. koritzae Lemoine, 1924; Lithophyllum cf. mengaudi Lemoine,1934. The name Lithothamnium is written with quotation marks because is not valid(see in Voelkerling, 1988), but the revision of the species referred to this genus isIargely incomplete. Thus we prefer to use the old name rather than ascribe "tout-court" all species to the revised genus Litbotbamnion.Laminar, massive, and hemispherical coral colonies mainly referable toAgathiphyllia rochatirw (Michelin, 1842), Antiguastrea lucasiara (Defrance, 1826), andHexastrea sp. form the framestones [species positive identifications are based on il-lustrations and descriptions given by Pfister (1977,1980,1985) and Frost (1981)1. Thenew species is the only algal content of this reef limestone.Stratigraphic distribution. Oligocene.BIBLIOGRAPHYAiroldi M. (1932) - Contributo allo studio delle Corallinacee del terziario italiano. 1". Le Coralli-nacee dell'Oligocene ligure-piemontese. Palaeont. Ital., Mern. Paleont., v. 33, pp. 55-83,Siena.Capeder G. (1900) - Contribuzione allo studio dei LithothamníonTerziari. Malpighia, v. 14, pp.172-1.82, Genova.Defrance M. (1826) - Polypiers. Dictionnaires Sc. Nat., v. 42, pp.377-398,Paris.Fravega P. & Vannucci G. (1980) - Segnalazione di una nuova specie di Lithophyllum: Lp. sassel-lense n. sp., nel "Rupeliano" superiore di Sassello (Bacino Ligure-Piemontese). Quad. kt,Geol. Unip. Genova, v. 1, n. 3, pp.31-37, Genova.Frost S. H. (1981) - Oligocene reef coral biofacies of the vicentin, Northeast ltaly. SEPM SpecialPublication, n. 30, pp. 483-539, Tulsa.Lemoine M. (Mme P.) (1924) - Contribution à l'étude demiocènes recueillies par M. Bourcart en Albanie.275-283, Paris.Lemoine M. (Mme P.) & Mengaud L. (1934) - AlguesSantander (Espagne). BulL Soc. Nat. Toulouse,v.66,Corallinacées fossiles. VII - MélobésiéesBull. Soc. Géol. France, s. 4, v. 23, pp.calcaires de l'Éocène de la province depp. r/r-róu, loulouse,274 P. Frar.rcga, M. Piazza tr G. VannucciMastrorilli V. I. (1968) - Nuovo contributo allo studio delle Corallinacee dell'Oligocene Ligure-Piemontese: i reperti della tavoletta Ponzone. Atti kt, Geol, Unio, Genozta, anno 5, v. 5, n.2, pp. 153-406, Genova.Michelin J. (1840-1847) - Iconographie zoophytologique. Description par localités et terrains despolypiers fossiles de France, et pays environnants. V. of 348 pp., Paris.Pfister T. (1977) - Das Problem der Variatiorubreite von Korallen am Beispel der oligozànenAntig.ustrea ltrcasiana (Defrance). Ecl. Geol. Heht., v.70, n. 3, pp. 825-843, Basel.Pfister T. (1980) - Systematische und palàoókologische Untersuchungen an oligozànen Korallender Umgebung von San Luca (Provinz Yicenza, Norditalien). Abh, Schweiz, Palàont. Ges.,v. 103, pp. 3-121, Basel.Pfister T. (1985) - Coral Fauna and Facies of the Oligocene Fringing Reef near Cairo Mon-tenotte (Liguria, Northern Italy). Facies, v. 13, pp. 175-226, Erlangen.Philippi R. (1837) - Beweis dass die Nulliporen Pflanzen sind. Arch. Naturgescb. Her. Dr, lY'ieg-tnann, v. 3, pp.387-393, Berlin.Ptazza M. (1989) - Evoluzione dell'evento trasgressivo, tardo-oligocenico, in alcuni settori delGruppo di Voltri. Nuovi dati per una ricostruzione paleogeografico-ambientale del marginemeridionale del Bacino Terziario del Piemonte. Y. oÍ 229 pp., E.R.S.U., Genova.\foelkerling \(/m.J. (1988) - The Coralline Red Algae: An Analysis of the Genera and Subfami-lies of Nongeniculate Corallinaceae. Y. of 268 pp., Oxford Univ. Press, Oxford.Receioed lane 10, 1993; accepted J*ly 21, 1993PLATE 1Fig. 1-3 - Litbopbyllum ippolitoi sp. n., Toleto Section, e level, holotype, 6V. 1) Section across the thallus; x50; 2) detail of an incomplete hypothallus and perithallus; x 300; 3) detail of conceptacles; x 120.PLATE 2Fig. 1-3 - Lithopbyllum ippolitoi sp. n., Toleto Section, e level, isotype, 6Va. 1) Section across the thallus; x40; 2) detail of hypothallus and perithallus; x 200; 3) detail of conceptacles; x 80.P. Fraoega et al. - O\goceneÈ1".,ffi=;.;P. Franega et al. - Oligocene Riv. It. Pal., v.99 - Tav. 2

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LITHOPHYLLUM IPPOLITOI. A NEW SPECIES OF CORALLINE ALGAE FROM TERTIARY PIEDMONT BASIN

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<em>LITHOPHYLLUM IPPOLITOI</em>. A NEW SPECIES OF CORALLINE ALGAE FROM TERTIARY PIEDMONT BASIN

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