Iguana b&w text K EI TH B IN N S 160 IGUANA • VOLUME 15, NUMBER 3 • SEPTEMBER 2008 BARRIO-AMORÓS AND RIVAS-FUENMAYOR Black Iguanas (Ctenosaura similis) range from southern Mexico through Central America to Panama. The species was not known to occur in South America until now. Other introduced populations are known from Florida and the Colombian islands of Malpelo and San Andres. Iguana 15.3 b&w text 9/10/08 5:44 AM Page 160 Ctenosaura similis is a large iguanid (see the excellent descrip- tion in Savage 2002) that ranges from southern Mexico through Central America to Panama. The species is unknown in South America, but has been introduced in Florida (Krysko et al. 2003) and the Colombian islands of Malpelo and San Andres (Forero-Medina et al. 2006). Around 1998, Eduard Asens (pers. comm.) noticed large iguanids in the Barcelona area. Only two large lizards with dis- tinctly different shapes, Tupinambis teguixin and Iguana iguana, are known from coastal Venezuela. These lizards were identified from photographs as Ctenosaura similis. Because the area is a port, the assumption is that the species arrived with cargo shipped from Central America. The area where the iguanas occur is heavily developed, and is centered around a storage and market center named Lecherías along the road from Barcelona to Puerto La Cruz in the state of Anzoátegui, where they occur in gardens, parking lots, and parks, but the population has expanded into adjacent natural dry habitats. Because only a few adult males have been seen, the sex ratio of this population appears to be female-biased, or per- haps composed largely of subadults. In the developed areas, they are quite tolerant of people. No specimens have been collected; consequently, the photographs presented herein are the only vouchers for the presence of C. similis in Venezuela. Ctenosaura similis is known to produce clutches of 12–88 (mean 43) eggs (Fitch and Henderson 1978). This species is mainly herbivorous but may feed opportunistically on inverte- brates and small vertebrates such as lizards, birds, eggs, and mammals. On Central American Caribbean islands, C. similis is known to prey on beach-nesting birds and marine turtle hatch- lings (Krysko et al. 2003). If the Venezuelan population expands to the east toward Mochima National Park or reaches the Paria Peninsula, it might pose a threat to nesting sea turtles (Chelonia mydas and Dermochelys coriacea). Although presumably subject to the same predators as Green Iguanas in the region, the pop- ulation appears to be reproducing effectively. A study investigating the extent and impact of C. similis in Venezuela is necessary to identify the possible threat this species poses to native plants and animals. The Venezuelan Ministerio del Ambiente, with the assistance of Venezuelan and interna- tional herpetologists with expertise in invasive populations of iguanas, should address the situation before control measures are no longer possible. Acknowledgments We thank Eduard Asens Pagés, Diego Flores Padrón, Piero Abbondanza, and Jose Alfredo Iglesias for sharing data. Gunther Köhler identified the species based on photographs. References Forero-Medina, G., O.V. Castaño-Mora, and M. Rodríguez-Melo. 2006. Ecología de Caiman crocodylus fuscus en San Andrés Isla, Colombia: Un studio preliminar. Caldasia 28:115–124. Savage, J.M. 2002. The Amphibians and Reptiles of Costa Rica. A Herpetofauna Between Two Continents, Between Two Seas. University of Chicago Press, Chicago, Illinois, USA. Fitch, H.S. and R.W. Henderson. 1978. Ecology and exploitation of Ctenosaura similis. University of Kansas Science Bulletin 51: 483–500. Krysko, K., F.W. King, K.M. Enge, and A.T. Reppas. 2003. Distribution of the introduced Black Spiny-tailed Iguana (Ctenosaura similis) on the south- western coast of Florida. Biological Sciences 66:74–79. Spiny-tailed Iguanas (Ctenosaura similis) in Venezuela: A Preliminary Report César Luis Barrio-Amorós and Gilson Rivas-Fuenmayor Fundación AndígenA, Apartado Postal 210, 5101-A Mérida, Venezuela (cesarlba@yahoo.com) IGUANA • VOLUME 15, NUMBER 3 • SEPTEMBER 2008 161SPINY-TAILED IGUANAS � Ctenosaurs in the Barcelona area occur in heavily modified habitats such as gardens, parking lots, and parks, but the population has expanded into adjacent natural dry habitats. This is one of the few adult males observed. ED U A R D A SE N S PA G ÉS Females are difficult to distinguish from subadult males. Most individ- uals fall into one of these classes, suggesting that the Barcelona popu- lation either is composed largely of adult females or is reproducing rap- idly, and the rising cohort of young males has yet to fully mature. ED U A R D A SE N S PA G ÉS Iguana 15.3 b&w text 9/10/08 5:44 AM Page 161