Haematozoans, mites and body condition in the oceanic island lizard Gallotia atlantica (Peters and Doria, 1882) (Reptilia: Lacertidae)

Abstract

We studied relationships among blood haemogregarines (Apicomplexa), ectoparasitic mites (Ophyonissus; Acari: Trombiculidae) and an endemic lizard host (Gallotia atlantica, Lacertidae) on an oceanic islet (Alegranza, Canary Islands). We asked whether blood infection, mite load and body condition were related in lizard subpopulations at two contrasting habitats. Both haemogregarine prevalence (100%) and intensity of parasitism (>1) were strikingly higher than values found for congeneric lizards from the other Canary Islands. There were few differences between habitats in infection levels, suggesting low influence of habitat on parasite performance. Both mite prevalence and intensity were very high, though only prevalence differed between habitats (higher in the richest and climatically more sheltered site). Body condition in lizards did not differ significantly between habitats. We found no association among blood parasite load, mite infection and lizard body condition. Results are discussed in the context of parasite‐host relationships on small islands as compared to larger areas such as continents.

Keywords:

• Body condition
• Gallotia atlantica
• haemogregarines
• lizards
• mite vector
• oceanic islet
• Ophyonissus
• parasites

Acknowledgements

We thank Miguel A. Hernández and Félix Medina for their support and help in the field in Alegranza. Thanks are due to Dr. Basilio Valladares, Dr. Antonio del Castillo and Dr. Fernando de Armas by their help in the laboratory. Alexis Rivera and Dr. Marcos Báez helped and supplied references for the study. Dr. Juan Carlos Casanova, Dr. Aurelio Martín and Dr. Manuel Nogales helped us with support, conseil and criticism. We thank the Gobierno de Canarias for permitting us to work on Alegranza in April 1996. The Armada Española, Zona Marítima de Canarias, gently transported us to the islet.