Floreana Lava-Lizard

Reptiles of Ecuador | Sauria | Tropiduridae | Microlophus | Microlophus grayii

Spanish common name: Lagartija de lava de Floreana.

Recognition: ♂♂ 24.4 cm ♀♀ 21.9 cm. Microlophus grayii is the only lava lizard occurring on Floreana Island and four of its surrounding islets. Males and females of this species differ from each other in size, shape, and coloration. Adult males are easily recognized by their raised black-and-whitish middorsal crest. They also have a brown body with scattered black blotches, as well as a distinctive black throat. Adult females may be recognized by their bright orange face.

Natural history: Extremely common. Microlophus grayii is a diurnal lizard inhabiting volcanic rock areas, dry shrublands, dry grasslands, deciduous forests, and urban areas.1 Floreana Lava-Lizards bask and forage on soil, rocks, and tree trunks up to 3.5 m above the ground.1 They move into the shade in order to avoide the hottest hours of the day, sitting on surfaces that have not been heated by the sun. Like other lava lizards,2 they probably spend the night hidden among rocks, beneath soil, and leaf litter.

Lizards of this species feed on insects and plant material such as fruits and seeds.3,4 When threatened, individuals of Microlophus grayii flee into crevices. If captured, they may shed the tail and bite.1 Floreana Lava-Lizards are preyed upon by Eastern Galápagos Racers (Pseudalsophis biserialis) and by domestic cats.1,5 Males perform pushup displays and fight with other males to defend their territories.1 Females build nests in sandy substrate close to rocks or vegetation.6

Conservation: Near Threatened.7 Microlophus grayii is listed in this category because the species is facing the threat of predation by housecats, but it has not been shown conclusively to have undergone population declines due to this threat.

Distribution: Microlophus grayii is endemic to an estimated 95 km2 area on Floreana Island and four of its surrounding islets: Caldwell, Champion, Enderby, and Gardner. Galápagos, Ecuador.

Distribution of Microlophus grayii Distribution of Microlophus grayii in and around Floreana Island

Etymology: The generic name Microlophus, which comes from the Greek words mikros (meaning “small”) and lophos (meaning “crest”), refers to the reduced dorsal crest in another lava lizard species (M. peruvianus).8 The specific epithet grayii honors British zoologist John Edward Gray (1800–1875),9 keeper of zoology at the British Museum in London from 1840 until 1874.

See it in the wild: Individuals of Microlophus grayii can be seen year-round with ~100% certainty on most tourism sites on Floreana Island. The best time to look for and photograph Floreana Lava-Lizards is during the first hours after sunrise or right before sunset, when the reptiles are active and approachable.

Special thanks to Paul Andrew Johnston for symbolically adopting the Floreana Lava-Lizard and helping bring the Reptiles of Ecuador book project to life.

Click here to adopt a species.

Authors: Alejandro Arteaga,aAffiliation: Tropical Herping (TH), Quito, Ecuador. Gabriela Aguiar, and Juan M GuayasaminbAffiliation: Laboratorio de Biología Evolutiva, Universidad San Francisco de Quito (USFQ), Quito, Ecuador.,cAffiliation: Galapagos Science Center, Galápagos, Ecuador.,dAffiliation: Centro de Investigación de la Biodiversidad y Cambio Climático, Universidad Tecnológica Indoamérica, Quito, Ecuador.

Academic reviewers: Edgar Benavides, John Rowe, and Cruz Márquez.

Photographers: Frank PichardoaAffiliation: Tropical Herping (TH), Quito, Ecuador. and Alejandro ArteagaaAffiliation: Tropical Herping (TH), Quito, Ecuador.

How to cite? Arteaga A, Aguiar G, Guayasamin JM (2020) Microlophus grayii. In: Arteaga A, Bustamante L, Vieira J, Guayasamin JM (Eds) Reptiles of Ecuador: Life in the middle of the world. Available from: www.reptilesofecuador.com

Literature cited:

  1. Field notes, Reptiles of Ecuador book project.
  2. Stebbins RC, Lowenstein JM, Cohen NW (1967) A field study of the lava lizard (Tropidurus albemarlensis) in the Galápagos Islands. Ecology 48: 839–851.
  3. Hervías-Parejo S, Heleno R, Rumeu B, Guzmán B, Vargas P, Olesen JM, Traveset A, Vera C, Benavides E, Nogales M (2018) Small size does not restrain frugivory and seed dispersal across the evolutionary radiation of Galápagos lava lizards. Current Zoology 65: 353–361.
  4. Washington Tapia, unpublished data.
  5. Christian EJ (2017) Demography and conservation of the Floreana racer (Pseudalsophis biserialis biserialis) on Gardner-by-Floreana and Champion islets, Galápagos Islands, Ecuador. PhD thesis, Auckland, New Zealand, Massey University.
  6. Burger J (1993) Colony and nest site selection in lava lizards Tropidurus ssp. in the Galápagos Islands. Copeia 1993: 748–754.
  7. Márquez C, Cisneros-Heredia DF (2016) Microlophus grayii. The IUCN red list of threatened species. Available from: www.iucnredlist.org
  8. Frost DR (1992) Phylogenetic analysis and taxonomy of the Tropidurus group of lizards (Iguania: Tropidurudae). American Museum Novitates 3033: 1–68.
  9. Uetz P, Freed P, Hošek J (2016) The Reptile Database. Available from: www.reptile-database.org