THE MEDlTERRANEAN GRAPTOLITIO FAUNA OF THE WENLODKlAN ln THE lberian PENINSULA

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1 THE MEDlTERRANEAN GRAPTOLITIO FAUNA OF THE WENLODKlAN ln THE lberian PENINSULA BY C. ROMARlZ *, A. ARCHE**, A. BARBA **, M. GUTIERREZ ELORZA *** and R. VEGAS *** ln other papers (ROMARIZ, 1962, 1969) an analysis was made oe the literatme eoncerning the Wenlockian graptolites oe southern Europe. As it was pointed then, DELGADO (1908) found at Valongo, North of Portugal, a peculiar fauna with speeies with very wide rhabdosomes. This geologist named those species Monogl'aptlls a, (3, 'I, and so on. GORTANI (1920) found in the Carnie Alps a fauna very similar to that of Valongo; latter on (1922) he studied the fauna of Goni (Sardinia) where there are several similar species. MARR (1925), HERITSCH (1934) and WATER LOT (1948) think of the possibility of a Wenlockian mesogea. As MARR says a larid barrier there would stand probably between 'the mediterranean sea an the north sea in the Wenlockian times. WATERLOT (1944) found in the North Pyrenees a similar fauna to that of Sardinia. There are also sardinian faunas at Maroe (WATERLOT, 1948; WILLEFERT, 1962). ROMARIZ (1962) made '.' Faculdade de Ciências e Centro de Estudos de Geologia Pura' e Aplicada. Lisboa. ** Departamento de Geología Económica (C. S. 1. C.). Madrid. **':' Departamento de ' Geomorfología y Geotectónica, Fac. de Ciências. Madrid.

2 58 a revision of the portuguese silurian graptolites and concluded that the Sardinian species are very common in the portuguese Wenlockian; he also classified several new species with similar characteristics from.the portuguese lower Salopian beds. He was SITUATION OF FOSSILIFBROUS BEDS OF CACERES AND HUESCA D Paleozoic ~PostherCyniOn coveroge Granltes and melomorphic rocks able to support the idea of a mediterranean Wenlodkian sea isolated from the north european seas. The mediterranean Wenlockian fauna is characterized hy wide rhabdosomes (usually more than -one centimeter) with few' thecae and smaller ones with a number of thecae higher than usual The

3 mediterranean fauna.isdominated hy peculiar species of Monog1'tt:ptJJS, Monodinzacisand P1'istiograptus and hy the scarcity of Cyrtograptus. 59 SITUAiTION OF WENLOCKIAN MEDITERRANIAN BEDS ln IBERIAN PENINSULA.. The.richness of lhe Wenlockian mediterranean fauna iri some beds, and the number of species recorded in Portugal, suggest that this country could have been the dispersion center of that fauna. The mediterranean fauna was laher recorded (ROMARIZ, 1969) in Galicia, north of Spain, and it was possible to define there, and in Portugal, some boundaries oe the mediterranean Wenlockian sea in the lberian Peninsula. Some tnonths ago M. Gutiérrez Elorza and R. Vegas collecred graptolitic fauna in the Guadarranque Syncline (Cáce-

4 res) -(1). The:studyóf this faunaby, ROMARIZ shóws. thit :the Wenlockian has a' tipicalmediteri:aneánfauná inwichthe following species are cotntnon:. Monograptus mutuliferus.. mutuliferus Gort lv1onoclimaci.r f/urrúndosae (Gort.)...» hemipristis (Menegh.em.Gort.).,»»gonii (Menegh.em.Gort.) ln the Southern Pyrenees was also recently col1ected a Slmllar fauna. A. Arche found in the Spanish Central Pyrenees in the Huesca province, the following species classified by ROMARIZ. 1) At Benasque, Puente de San Jaime (2) are present: Monograptus mutuliferus mutuliferus Gort.» lamarm.orae Menegh.em.Gort.» flemingi flemingi Salt.» latus Me Coy 2) At Sierra Negra, north of Pico de Espax (3): Monograptus mutuliferus mutuliferus Gprt.» lamarmorae Menegh.em.Gort.» uncinatus taricoi Gort.» monoclimacis flumendosae (Gort.) A. Barba found also similiar fauna at Valle de Héas, Montagne de Pourboucou, at Department des Haures Pyrenees ln the French Pyrenees (4). ROMARIZ classifiedthe following species: Monograptus mutuliférus st1'ígosus Gart..» flemingi flemingi Salt.» latus Me Coy The finding of this newwenlockiím outcrops with mediterranean graptolites helps to define the extension of the mediterranean Silurian sea through the 11orth, the cenvet and the south east of Spain and contributes :to a more precise defiriition of the South Wenlockian Sea..

5 61 REFERENCES DELGADO, J. F. NERY (1908) - Systeme Silurique du Portugal. Mem. Servo Geol. POItllgal. GORTAN1, M. (1920) - Contribuzione aho studio dei paleozoico-carnieo. Parte VI - Faune a Graptoliti. Paleontographia Ita/ica, vol. XXVI. (1922) - Faune Paleozoiehe della Sardegna. Parte I. Le Graptoliti di Goni. Paleontographia Italica, vol. XXVIII. (1922a) - f1aune Paleozoiche della Sardegna. Parte II. Graptoliti della Sardegna oriental e, Paleontographia Italica, vol XXVIII. HERATSCH, F. (1934) - The graprolitie faunas of the Gotlandian in the Eastem Alps and their rdationships. Geol. Mag, voi. LXXI. MARR, J. ie.(1925) - CondiÜOl1s of deposition of t'he Stoe~dale Shales of the Lake District. Quart. J ottrn. Geol. Soc. ROMARIZ, C. (1962) - Graptolitos do Silúrico português - Rev. Fac. Ciênc. Lisboa - l." sér., vol. x,.fasc. 2.. ROMAR1Z, C. (1969) - Graptolitos silúricos do noroeste peninsular,com. Servo Geol. Portugal, tom. LIlI. WATERLOT, C. (1944) - Sur l'e~tension au Pays basque de la gr.ande.faune graptolitique de Sardaigne. Bttll. Servo Carte Géol. France, 'bom. LV, n.o 216, p {1948) - La faune graptolitique spécial à la mésogéea occidentale. C. R. Acad. Sc., tom. 226, p. 68l. WILLEFERT, S. (1962) - Quelques Graptolites du silurien supérieur du Sahara septentrionai. Bttll. Soc. Geol. de France, 7. a sec., tom. IV. (1963) - Graptolites du siluri-en et du Loehkovien de Touchchent (anticlinorium de Kasba-Tadrla-Arzon, Maroe central). Notes Servo Geol. Maroc, tom. 23, n.o 172.