Iguana_11.1_bw_text 14 IGUANA • VOLUME 11, NUMBER 1 • MARCH 2004 GIFFORD AND POWELL The Lower Barahona Peninsula is that portion of the peninsula south of the Sierra de Baoruco. Because the region lies in the rainshadow of the mountain range, the lower elevations get little rain and are characterized by dry tropical forest. Until recently, four species of Ameiva were thought to occur in the region: Ameiva chrysolaema, A. leberi, A. lineolata, and A. taeniura. Of the four, A. lineolata is the smallest (maximum known snout-vent length = 59 mm) and the most xerophilic (tolerant of harsh, dry conditions). This species, featuring a bright blue tail and feet, has a disjunct range in similar habitats across the island of Hispaniola. Ameiva tae- niura is intermediate in size (SVL to 103 mm), the least drought tolerant, and is restricted largely to the relatively few and scattered moist microhabitats. Although, at some sites, one can stand in one place and see individuals of dif- ferent species, closer observation reveals that A. taeniura only rarely leaves the cooler, shaded areas where canopy cover is relatively dense. In the same study that revealed the habitat association of A. taeniura, the authors found no significant differences in microhabitat use by A. chrysolaema and A. leberi, which are comparable in size (SVL to 160 mm in some popula- tions). The former species is widely distributed across Hispaniola, whereas the latter is known only from the peninsula. They are distinguished in that the back and sides of A. chrysolaema ficta, the subspecies found in the area, is distinctly patterned, whereas A. leberi is unicolored. Because other populations of A. chrysolaema are known to have unicolored pattern variants and because no ecological differences were evident, the authors suggested that A. chrysolaema and A. leberi were, in fact, pattern variations of a single species. More recent genetic studies have verified that contention. One of those studies also determined that A. chryso- laema from the peninsula was distinctive relative to popu- lations elsewhere on Hispaniola. This is not surprising, because the island actually is a composite of two paleois- S P E C I E S P R O F I L E The Ground Lizards (Ameiva) of the Lower Barahona Peninsula Matthew E. Gifford1 and Robert Powell2 1Washington University, St. Louis, Missouri 2Avila University, Kansas City, Missouri Photographs by Robert Powell. (4) Two persons should be employed to monitor the area where C. ricordii is present. These persons should be from the local community and should have an excellent knowl- edge of the terrain and the target species. They should con- trol the persecution of iguanas and stop illegal habitat destruction by surveying the area, advising people regard- ing harmful practices, and reporting to the appropriate authorities, as necessary. (5) The socioeconomic aspect of iguana hunting and con- sumption in Pedernales should be investigated. (6) Educational programs must be developed that not only address the general public, but will serve to open a dialogue with the target group of persons in Pedernales involved in iguana persecution. Reference Ottenwalder, J.A. 1999. Ricord’s Iguana, Cyclura ricordii, pp. 51–55. In: A. Alberts (comp. & ed), West Indian Iguanas: Status Survey and Conservation Action Plan. IUCN/SSC West Indian Iguana Specialist Group. IUCN, Gland, Switzerland and Cambridge, UK. Acknowledgments We thank John Binns and Robert Powell for improvements on an early draft. We express gratitude to Máximo Aquino, Subsecretario de Recursos Forestales, Secretaría de Medio, Ambiente y Recursos Naturales, for logistical support and the Dominican Armed Forces for the helicopter flight. Special thanks go to Salvador P. Mella from Pedernales, who accompanied us in the field and whose knowledge of iguanas was invaluable. IGUANA • VOLUME 11, NUMBER 1 • MARCH 2004 15SPECIES PROFILE lands that have become joined only recently, at least by geo- logical standards. The Barahona Peninsula is part of the South Island, whereas most of Hispaniola is derived from the North Island. This, however, raises the additional ques- tions of where A. chrysolaema originated and how the ances- tors of today’s lizards colonized the other paleoisland. Only tentative answers are possible because genetic data from Haitian populations are missing and currently unavailable (due to the difficulties and dangers of conduct- ing fieldwork in Haiti) and data from the Dominican Republic are inconclusive. Presumably, A. chrysolaema stock originally became established in the north. Descendants expanded their range into the lowlands to the south and east, and some of those migrating to the south apparently reached the South Island during one of the periods when sea levels were low and the intervening channel was exposed. Subsequently isolated by rising sea levels, the South Island population became distinct from its relatives to the north. So, should A. chrysolaema ficta be considered a species separate from its North Island counterparts? Probably; but a definitive answer must await the analysis of Haitian mate- rial. In the interim, however, A. chrysolaema, as currently defined, probably is best and most accurately referred to as a “species complex,” a group of closely related species in which the species boundaries often are poorly defined. Since both A. lineolata and A. taeniura are found on both paleoislands, one has to wonder if further research will show a pattern similar to that which seems to best explain the situation in the A. chrysolaema complex. References Gifford, M.E., R. Powell, and R.L. Gutberlet, Jr. In review. Geographic variation in mitochondrial DNA haplotypes in a widespread teiid lizard (Ameiva chrysolaema) on Hispaniola. Molecular Phylogenetics and Evolution. Hower, L.M. and S.B. Hedges. 2003. Molecular phylogeny and bio- geography of West Indian teiid lizards of the genus Ameiva. Caribbean Journal of Science 39:298–306. Schell, P.T., J.S. Parmerlee, Jr., and R. Powell. 1993. Ameiva chryso- laema. Catalogue of American Amphibians and Reptiles (563):1–6. Schwartz, A. and R.W. Henderson. 1991. Amphibians and Reptiles of the West Indies: Descriptions, Distributions, and Natural History. University of Florida Press, Gainesville. Schwartz, A. and R.F. Klinikowski. 1966. The Ameiva (Lacertilia: Teiidae) of Hispaniola. II. Geographic variation in Ameiva chrysolaema Cope. Bulletin of the Museum of Comparative Zoology 133:425–487. Sproston, A.L., R.E. Glor, L.M. Hartley, E.J. Censky, R. Powell, and J.S. Parmerlee, Jr. 1999. Niche differences among three sympatric species of Ameiva (Reptilia: Teiidae) on Hispaniola. Journal of Herpetology 33:131–136. Ameiva taeniura is least drought tolerant and is restricted to rela- tively moist microhabitats on the peninsula. Ameiva lineolata, with its distinct stripes and electric blue tail and feet, is the most drought-tolerant species. The unicolored phase of Ameiva chrysolaema was until recently thought to be a distinct species, A. leberi. Peninsular Ameiva chrysolaema come in two pattern phases; this phase is characterized by distinct spots and bars.