Conservation Genetics

, Volume 19, Issue 6, pp 1461–1469 | Cite as

Molecular data exclude current hybridization between iguanas Conolophus marthae and C. subcristatus on Wolf Volcano (Galápagos Islands)

  • Livia Di Giambattista
  • Arianna Fulvo
  • Anna Fabiani
  • Jessica Bonanni
  • Jorge E. Carrión
  • Gabriele GentileEmail author
Research Article


Natural hybridization may influence population fitness and responsiveness to natural selection, in particular in oceanic island systems. In previous studies, interspecific hybridization was detected between the Galápagos iguana species Amblyrhynchus cristatus and Conolophus subcristatus. Further, possible hybridization was also suggested to occur between C. subcristatus and C. marthae at Wolf Volcano on Isabela Island. In this work, we investigated the level of hybridization between C. subcristatus and C. marthae using a large set of microsatellite markers. Results indicated strong differentiation between species and, while we cannot rule out hybridization in the past, there is no evidence of ongoing hybridization between C. marthae and C. subcristatus. These findings have great importance for the design of management actions and conservation plans, in particular for the purposes of a head start program. However, because potential for hybridization may change under different environmental and demographic conditions, genetic characterization of newly marked individuals of C. marthae and C. subcristatus in Wolf Volcano should not be interrupted.


Hybridization Introgression Reproductive isolation mechanisms Pink Iguana 



We gratefully thank the park rangers of the Galápagos National Park for their invaluable support and friendship. We thank Michel Milinkovitch for kindly providing data. We thank Philip Hedrick and Mark Welch for their valuable criticism. This work is in the frame of a long term partnership between the University Tor Vergata and the Galápagos National Park Directorate, aimed at conservation of Galápagos iguanas. This work was supported by the Mohamed bin Zayed Species Conservation Fund with a grant to GG (Project No. 12254183;

Compliance with ethical standards

Conflict of interest

Authors declare no conflict of interest.

Ethical approval

Animal manipulation and blood sampling were performed according to a protocol that minimized animal stress, in accordance with the European Community guidelines and with the approval of the Galápagos National Park Directorate. Samples were exported and imported under the CITES permits 101/BG and IT/IM/2015/MCE/01711.

Supplementary material

10592_2018_1114_MOESM1_ESM.pdf (443 kb)
Supplementary material 1 (PDF 442 KB)
10592_2018_1114_MOESM2_ESM.xlsx (59 kb)
Supplementary material 2 (XLSX 59 KB)


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Copyright information

© Springer Nature B.V. 2018

Authors and Affiliations

  1. 1.Department of BiologyUniversity of Rome Tor VergataRomeItaly
  2. 2.Galápagos National Park DirectorateGalápagosEcuador

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