Contributions on vertebrate paleontology in Venezuela Preface

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Pal&ontologische Zeitschrift

2008, Vol. 82/2, p. 103-104, 30-06-2008

Contributions on vertebrate p a l e o n t o l o g y in V e n e z u e l a

Preface

MARCELO R. S,~,NCHEZ-VILLAGRA, Z f i r i c h & ORANGEL A. AGUILERA, C o r o

Venezuela, located in the septentrional area of South A m e r i c a in the Caribbean, is considered one of the "megadiverse" countries in the world, belonging to the list of 15 countries with highest species diversity (RO- DRIGUEZ & ROJAS-SUAREZ 1999), including vertebrates of all kinds, m a n y currently being described (e.g., LEw et al. 2006). This richness is in contrast with one of the poorest k n o w n vertebrate fossil records in the continent. This is regrettable, as Venezuela has been hypothesized to have b e e n at critical geographical positions to under- stand biogeographic and evolutionary patterns at different times during the Phanerozoic (e.g., ITURRALDE-VI- NENT & MACPHEE 1999; YOUNG & MODY 2002). Vene- zuela is situated in tropical America, and the tropics have been hypothesized as being cradle and museum for evolution: centers of origin of vertebrate diversity and reservoirs of basal clades extinct in higher latitudes (JA- BLONSKI et al. 2006). The Orinoco river is also a major

reservoir o f freshwater diversity and its past h i s t o r y m u s t have b e e n a f u n d a m e n t a l factor in shaping the c o m m u - nities o f o r g a n i s m s that inhabit the northern Neotropics. T h e total a r e a of Venezuela is little over 9 0 0 . 0 0 0 k m 2, and f r o m it a contribution to the understanding o f the bio- c h r o n o l o g y o f South A m e r i c a n vertebrates, so m u c h bi- ased t o w a r d s the Southern cone, is expected.

T h e first step to study evolutionary patterns in d e e p time is describing the paleobiodiversity. In this collec- tion o f papers, we continue our ongoing efforts to study Venezuelan vertebrate paleontology by b r i n g i n g into print descriptions and reviews o f t a x a f r o m a g e o c h r o n o l - o g y sequences in different s e d i m e n t a r y basins a n d pa- l e o e n v i r o n m e n t s (AGUILERA 2004, 2006; SANCHEZ- VILLAGRA ~¢ CLACK 2004; SANCHEZ-VILLAGRA 2006). Besides the descriptions of the results o f o u r o w n col- lecting efforts, we have organized the study of m a t e r i a l in existing collections mostly in the cities o f Coro, Uru-

Fig. 1. The classic Urumaco locality of "El Mam6n", where many significant fossil vertebrates have been found and where some of the early oil exploration in the area was conducted. Photo courtesy of Fernando Acosta (Universi- dad Nacional Experimental Francisco de Miranda).

Addresses of the authors: Marcelo R. S~inchez-Villagra, Paliiontologisches Institut und Museum, Universit~it Zfirich, Karl Schmid- Strasse 4, CH-8006 Ziirich, Switzerland; e-mail <[email protected]>. - Orangel A. Aguilera, Universidad Nacional Experi- mental Francisco de Miranda, Centro de Investigaciones en Ciencias Bfisicas, Complejo Docente Los Perozo, Carretera Variante Sur, Coro, 4101, Estado Falc6n, Venezuela; e-mail <[email protected]>.

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MARCELO R. S/~,NCHEZ-VILLAGRA & ORANGEL A. AGUILERA m a c o , Caracas, and Maracaibo. Collaborations with ex-

perts on different t a x o n o m i c groups h a v e made this possible, and we are grateful to the invited authors for their excellent contributions.

We t h a n k Michael A m l e r and Oliver Rauhut for the o p p o r t u n i t y to publish contributions on this fauna in a single issue of this journal. We would like to especially t h a n k our colleagues A l f r e d o Carlini and Ken Johnson for their great input in this phase o f this project, a n d our colleagues in the field, Rodolfo S~inchez, Cathy Villal- ba, R o b e r t o Lozs~in, and A l f r e d o Zurita, for their hard work and comradeship. We also t h a n k the financial sup- p o r t o f the University o f Ztirich, o f the "Fonds zur F6rderung des a k a d e m i s c h e n N a c h w u c h s e s (FAN) des Ztircher Universit~itsvereins ( Z U N I V ) " for supporting T. Scheyer and the work in the M e s o z o i c and o f the Uni- versidad Nacional E x p e r i m e n t a l F r a n c i s c o de Miranda, which m a d e this work possible.

R e f e r e n c e s

AGUILERA, O. 2004. Tesoros paleontol6gicos de Venezuela: Urumaco, Patrimonio Natural de la Humanidad. - 147 p., Caracas (Edito- rial Arte).

AGUILERA, O. 2006. Tesoros Paleontol6gicos de Venezuela: El Cuater- nario del Nordeste del Estado Falc6n. - 120 p., Caracas (Edito- rial Arte).

ITURRALDE-VINENT, M.A. & MACPHEE, R.D.E. 1999. Paleogeogra- phy of the Caribbean region: Implications for Cenozoic biogeo- graphy. - Bulletin of the American Museum of Natural History 238: 1-95.

JABLONSKI, D.; ROY, K. & VALENTINE, JW. 2006. Out of the Tropics: Evolutionary dynamics of the latitudinal diversity gradient. - Science 314: 102-106.

LEW, D.; PI~REZ-HERNANDEZ, R. & VENTURA, J. 2006. Two new spe- cies of Philander (Didelphimorphia, Didelphidae) from north- ern South America. - Journal of Mammalogy 87: 224-237. RODRfGUEZ, J.P. & ROJAS-SUAREZ, F. 1999. Libro Rojo de la Fauna

Venezolana. 2 na ed. - 472 p., Caracas (Provita & Fundaci6n Po- lar).

SANEHEZ-VILLAGRA, M.R. & CLACK, J.A., eds., 2004. Fossils of the Castillo Formation, Venezuela: Contributions on Neotropical Palaeontology. - Special Papers in Palaeontology 71:1-112. SANCHEZ-VILLAGRA, M.R. & AGUILERA, O. 2006. Neogene verte-

brates from Urumaco, Falc6n State, Venezuela: diversity and significance. - Journal of Systematic Palaeontology 4: 213- 220.

YOUNG, G.C. & MOODY, J.M. 2002. A Middle-Late Devonian fish fauna from the Sierra de Perij~i, western Venezuela, South Ame- rica. - Mitteilungen des Museums fi.ir Naturkunde Berlin, Geo- wissenschaftliche Reihe 5: 155-206.