Published October 10, 2019. Updated March 31, 2026. Open access. Peer-reviewed. | Purchase book ❯ |
Floreana Lava-Lizard (Microlophus grayii)
Reptiles of Ecuador | Sauria | Tropiduridae | Microlophus grayii
English common name: Floreana Lava-Lizard.
Spanish common names: Lagartija de lava de Floreana, lagartija de lava de Gray.
Recognition: ♂♂ 24.4 cmMaximum distance from the snout to the tip of the tail. Snout–vent length=9.8 cm. ♀♀ 21.9 cmMaximum distance from the snout to the tip of the tail. Snout–vent length=7.1 cm..1,2 Microlophus grayii is the only lava lizard inhabiting Floreana Island and three of its surrounding islets. It is easily distinguished from other native lizards (iguanas and leaf-toed geckos) by its keeled tail scales, a skin fold above the shoulder, and a conspicuously enlarged interparietal scale.1 Adult males are recognized by a prominent black-and-white mid-dorsal crest and a distinctive black throat, while adult females feature a bright orange face (Fig. 1).1 This species closely resembles M. slevini in coloration and lepidosis but differs from the latter by possessing fewer gular and more loreal scales.2
Figure 1: Individuals of Microlophus grayii from Puerto Velazco Ibarra, Floreana Island, Galápagos, Ecuador. j=juvenile.
Natural history: Microlophus grayii is a diurnal lizard found in high densities across Floreana Island, inhabiting volcanic rocky areas, dry shrublands, grasslands, deciduous forests, and urban environments.1 During the early morning and late afternoon, individuals are frequently seen basking or foraging on soil, rocks, and tree trunks up to 3.5 m above the ground.1 To thermoregulate during the hottest hours, they retreat to shaded, unheated surfaces, eventually spending the night concealed beneath rocks, soil, or leaf-litter.1 The diet of M. grayii is omnivorous, consisting of insects as well as plant material such as fruits and seeds.1,3 Known predators include the Galápagos Racer (Pseudalsophis biserialis) and domestic cats.1,4 Socially, males are highly territorial, defending their areas through push-up displays and physical combat.1 Reproduction involves females nesting in sandy substrates near protective rocks or vegetation.5
Conservation: Near Threatened Not currently at risk of extinction, but requires some level of management to maintain healthy populations..6 Microlophus grayii is listed in this category because the species is confined to Floreana and three of its associated islets, covering an area no greater than 100 km2. Being a small island, Floreana is susceptible to invasive predators, particularly cats, which have been confirmed as predators of M. grayii.1 Nevertheless, the species has not been shown conclusively to have undergone population declines due to this threat.
Distribution: Microlophus grayii is endemic to the Galápagos Archipelago, Ecuador, where it occupies an estimated area of 94 km2 across Floreana Island and three of its satellite islets: Caldwell, Champion, and Enderby (Figs 2, 3).
Figure 2: Distribution of Microlophus grayii in Galápagos. See Appendix 1 for a complete list of the presence localities included in the map.
Figure 3: Distribution of Microlophus grayii in Floreana Island. See Appendix 1 for a complete list of the presence localities included in the map.
Etymology: The generic name Microlophus is derived from the Greek words mikros (small) and lophos (crest).1 The specific epithet grayii honors the British zoologist John Edward Gray (1800–1875),7 who served as the Keeper of Zoology at the British Museum from 1840 to 1874.
See it in the wild: Microlophus grayii can be observed year-round with high reliability. The most accessible locations are the outskirts of Puerto Velazco Ibarra, particularly along the coastal trail leading toward La Lobería.
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: Fundación Khamai, Reserva Arlequín, Ecoruta Paseo del Quinde km 56, Santa Rosa de Mindo, Pichincha 171202, Ecuador. Gabriela Aguiar,bIndependent researcher, Quito, Ecuador. and Juan M GuayasamincAffiliation: Universidad San Francisco de Quito, Quito, Ecuador.
Academic reviewers: Edgar Benavides,dAffiliation: Yale University, New Have, USA. John Rowe,eAffiliation: Alma College, Alma, USA. and Cruz MárquezfAffiliation: University of Rome Tor Vergata, Rome, Italy.
Photographers: Alejandro ArteagaaAffiliation: Fundación Khamai, Reserva Arlequín, Ecoruta Paseo del Quinde km 56, Santa Rosa de Mindo, Pichincha 171202, Ecuador. and Frank PichardogAffiliation: Tropical Herping (TH), Quito, Ecuador.
How to cite? Arteaga A, Aguiar G, Guayasamin JM (2026) Floreana Lava-Lizard (Microlophus grayii). In: Arteaga A, Bustamante L, Vieira J (Eds) Reptiles of Ecuador: Life in the middle of the world. Available from: www.reptilesofecuador.com. DOI: 10.47051/ATGH7471
Literature cited:
- Arteaga A, Bustamante L, Vieira J, Tapia W, Guayasamin JM (2019) Reptiles of the Galápagos: life on the Enchanted Islands. Tropical Herping, Quito, 208 pp. DOI: 10.47051/AQJU7348
- Torres-Carvajal O (2024) A new species of lava lizard (Iguanidae: Tropidurinae: Microlophus) from the Galápagos. Zootaxa 5428: 058–074. DOI: 10.47051/AQJU7348
- 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. DOI: 10.1093/cz/zoy066
- 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, Massey University, 186 pp.
- Burger J (1993) Colony and nest site selection in lava lizards Tropidurus ssp. in the Galápagos Islands. Copeia 1993: 748–754.
- Márquez C, Cisneros-Heredia DF (2016) Microlophus grayii. The IUCN Red List of threatened species. Available from: www.iucnredlist.org. DOI: 10.2305/IUCN.UK.2016-1.RLTS.T48444750A48444762.en
- Uetz P, Freed P, Hošek J (2016) The Reptile Database. Available from: www.reptile-database.org
Appendix 1: Locality data used to create the distribution map of Microlophus grayii in Ecuador (Fig. 2). Go to the section on symbols and abbreviations for a list of acronyms used.
| Country | Province | Locality | Source |
| Ecuador | Galápagos | Bahía de las Cuevas | iNaturalist; photo examined |
| Ecuador | Galápagos | Bahía La Baronesa | Benavides et al. 2009 |
| Ecuador | Galápagos | Black Beach, 4.8 km NE of | Torres-Carvajal 2024 |
| Ecuador | Galápagos | Caldwell islet | Benavides et al. 2009 |
| Ecuador | Galápagos | Champion islet | Torres-Carvajal 2024 |
| Ecuador | Galápagos | Enderby islet | Van Denburgh and Slevin 1913 |
| Ecuador | Galápagos | La Lobería | Arteaga et al. 2019 |
| Ecuador | Galápagos | Las Cuevas | Benavides et al. 2009 |
| Ecuador | Galápagos | Lava pile near lagoon | Torres-Carvajal 2024 |
| Ecuador | Galápagos | Post Office bay | Torres-Carvajal 2024 |
| Ecuador | Galápagos | Post Office bay, 2 km S of | iNaturalist; photo examined |
| Ecuador | Galápagos | Puerto Flores | iNaturalist; photo examined |
| Ecuador | Galápagos | Puerto Velazco Ibarra | Arteaga et al. 2019 |
| Ecuador | Galápagos | Puerto Velazco Ibarra, 2 km SE of | Arteaga et al. 2019 |
| Ecuador | Galápagos | Punta Ayora | Benavides, 2007 |
| Ecuador | Galápagos | Punta Cormorán | Van Denburgh and Slevin 1913 |
| Ecuador | Galápagos | Punta Ensillada | iNaturalist; photo examined |
| Ecuador | Galápagos | Punta Sur | Arteaga et al. 2019 |
| Ecuador | Galápagos | Unnamed road 1 | iNaturalist; photo examined |