Published October 10, 2019. Updated January 25, 2024. Open access. Peer-reviewed. | Purchase book ❯ |
Santa Cruz Lava-Lizard (Microlophus indefatigabilis)
Reptiles of Ecuador | Sauria | Tropiduridae | Microlophus indefatigabilis
English common name: Santa Cruz Lava-Lizard.
Spanish common name: Lagartija de lava de Santa Cruz.
Recognition: ♂♂ 23.2 cmMaximum distance from the snout to the tip of the tail. Snout–vent length=9.0 cm. ♀♀ 17.9 cmMaximum distance from the snout to the tip of the tail. Snout–vent length=7.3 cm..1,2 Microlophus indefatigabilis is easily distinguishable from other native lizards occurring on Floreana Island (that is, iguanas and leaf-toed geckos) by having keeled scales on the tail, a skin fold above the shoulder, a raised mid-dorsal crest, and a conspicuously enlarged interparietal scale.1 Microlophus indefatigabilis is the only lava lizard known to occur on Baltra, Santa Cruz, Seymour Norte, and 13 of the surrounding islets of these islands. Males and females of this species differ from each other in size, shape, and coloration.1 Adult males are easily recognized by their raised middorsal crest. They also have a brown body with scattered black and white blotches, as well as a distinctive red and black throat and a black chest (Fig. 1).1 Adult females usually have a mostly uniform brownish body, bright orange face, and a black mark at shoulder level.1
Figure 1: Individuals of Microlophus indefatigabilis from El Garrapatero, Santa Cruz Island, Galápagos, Ecuador. j=juvenile.
Natural history: Microlophus indefatigabilis is a diurnal lizard that inhabits volcanic rock areas, dry shrublands, dry grasslands, seasonally dry forests, and urban areas.1 Santa Cruz Lava-Lizards bask and move over comparatively large (64–1,377 m2) territories, spending up to 99% of the time on rocks, but also on soil, leaf-litter, shrubs, cacti, and walls up to 4.5 m above the ground.1–4 They move into the shade during hot midday hours, sitting on surfaces that have not been heated by the sun.2 At night, they sleep on rocky outcrops1 or remain hidden among rocks, beneath soil, and under leaf-litter.2,3 Male Santa Cruz Lava-Lizards are faster and have greater stamina than females.5,6 They also keep harems and are able to defend only about 20% of their overall home range territories,3,4 which they guard by performing pushup displays and fighting with intruders.1 They defend themselves by fleeing into crevices, shedding the tail, and biting.1 Lizards that occur in habitats with relatively little vegetation cover have greater levels of sprint speed, endurance, and wariness.5–7 Microlophus indefatigabilis is the most frugivorous of the Galápagos lava lizards.8 The diet includes fruits, seeds, and flowers, but also insects (termites, beetles, flies, maggots, ants, caterpillars, moths, antlions, aphids, leaf hoppers, and grasshoppers), crustaceans, spiders, scorpions, centipedes, geckos (Lepidodactylus lugubris), members of their own species, and their own shed skin.1,2,8,9 In urban areas, Santa Cruz Lava-Lizards have been observed opportunistically feeding on breadcrumbs, macaroni, meat scraps, and dog food,2 although this is not a natural behavior. These reptiles obtain water from their diet and by drinking precipitation that accumulates on leaves.2 Predators include hawks, owls, herons, mockingbirds, snakes (Pseudalsophis dorsalis and P. steindachneri), and housecats.10–12 The breeding season peaks in February and March, but may start in November. Females lay 1–6 eggs per clutch2,13 in 20 cm deep nests14 that are excavated in loose soil or sand usually close to rocks or vegetation.15 They protect their nests from potential predators and from other females.15
Conservation: Least Concern Believed to be safe from extinction given current circumstances..16 Microlophus indefatigabilis is listed in this category because there is no conclusive evidence that the species is undergoing population declines.16 Santa Cruz Lava-Lizards are abundant and occur on three islands and 13 islets. However, immediate threats include invasive predators,11 road traffic,10 and the loss of habitat due to agriculture.
Distribution: Microlophus indefatigabilis is endemic to an area of approximately 773 km2 on Baltra, Santa Cruz, and Seymour Norte islands, as well as 13 of their surrounding islets (Caamaño, Dahpne Major, Edén, Guy Fawkes Este, Guy Fawkes Norte, Guy Fawkes Oeste, Guy Fawkes Sur, Mosquera, Plaza Norte, Plaza Sur, Punta Bowditch Norte, Punta Bowditch Sur, and Venecia)1,17 in Galápagos, Ecuador (Figs 2, 3).
Figure 2: Distribution of Microlophus indefatigabilis in Galápagos. See Appendix 1 for a complete list of the presence localities included in the map.
Figure 3: Distribution of Microlophus indefatigabilis in Santa Cruz Island. See Appendix 1 for a complete list of the presence localities included in the map.
Etymology: The generic name Microlophus comes from the Greek words mikros (=small) and lophos (=crest).1 The specific epithet indefatigabilis refers to Santa Cruz, previously known as Indefatigable Island.1
See it in the wild: Santa Cruz Lava-Lizards can be seen year-round with complete certainty at most tourism sites on and around Santa Cruz Island, including Daphne Major, Plaza Sur, and Seymour Norte islands. The best time to look for and photograph the lizards is during the first hours after sunrise or right before sunset.
Authors: Alejandro Arteaga,aAffiliation: Khamai Foundation, Quito, 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.
Photographer: Jose VieiragAffiliation: Tropical Herping (TH), Quito, Ecuador.,hAffiliation: ExSitu, Quito, Ecuador.
How to cite? Arteaga A, Aguiar G, Guayasamin JM (2024) Santa Cruz Lava-Lizard (Microlophus indefatigabilis). 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/IJLD8949
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
- Stebbins RC, Lowenstein JM, Cohen NW (1967) A field study of the lava lizard (Tropidurus albemarlensis) in the Galápagos Islands. Ecology 48: 839–851. DOI: 10.2307/1933742
- Rowe JW, Martin CE, Clarck DL (2019) Habitat use and spatial ecology of three Microlophus lizard species from Santa Cruz and San Cristóbal islands, Galápagos, and the coastal dry forest of Machalilla, Ecuador. Herpetological Review 50: 43–51.
- Stone P, Baird T (2002) Estimating lizard home range: the Rose Model revisited. Journal of Herpetology 36: 427–436. DOI: 10.2307/1566187
- Snell HL, Jennings RD, Snell HM, Harcourt S (1988) Intrapopulation variation in predator-avoidance performance of Galápagos lava lizards: the interaction of sexual and natural selection. Evolutionary Ecology 2: 353–369. DOI: 10.1007/BF02207566
- Miles DB, Snell HL, Snell HM (2001) Intrapopulation variation in endurance of Galápagos lava lizards (Microlophus albemarlensis): evidence for an interaction between natural and sexual selection. Evolutionary Ecology Research 3: 795–804.
- Jordan MA, Snell HL, Snell HM, Jordan WC (2005) Phenotypic divergence despite high levels of gene flow in Galápagos lava lizards (Microlophus albemarlensis). Molecular Ecology 14: 859–867. DOI: 10.1111/j.1365-294X.2005.02452.x
- 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
- Lewbart GA, Valle CA, Muñoz-Perez JP (2017) Microlophus indefatigabilis (Lava Lizard) diet. Herpetological Review 48: 851–852.
- Tanner D, Perry J (2007) Road effects on abundance and fitness of Galápagos lava lizards (Microlophus albemarlensis). Journal of Environmental Management 85: 270–278. DOI: 10.1016/j.jenvman.2006.08.022
- Konecny MJ (1987) Food habits and energetics of feral house cats in the Galápagos Islands. Oikos 50: 24–32. DOI: 10.2307/3565398
- Townsend CH (1930) The Astor Expedition to the Galápagos Islands. Bulletin of the New York Zoological Society 33: 135–155.
- Van Denburgh J, Slevin JR (1913) Expedition of the California Academy of Sciences to the Galápagos Islands, 1905-1906. IX. The Galapagoan lizards of the genus Tropidurus with notes on iguanas of the genera Conolophus and Amblyrhynchus. Proceedings of the California Academy of Sciences 2: 132–202.
- Carpenter CC (1970) Miscellaneous notes on Galápagos lava lizards (Tropidurus: Iguanidae). Herpetologica 26: 377–386.
- Burger J (1993) Colony and nest site selection in lava lizards Tropidurus ssp. in the Galápagos Islands. Copeia 1993: 748–754. DOI: 10.2307/1447237
- Márquez C, Cisneros-Heredia DF (2016) Microlophus indefatigabilis. The IUCN Red List of threatened species. Available from: www.iucnredlist.org. DOI: 10.2305/IUCN.UK.2016-1.RLTS.T88793749A88793762.en
- Jordan MA, Snell HL (2008) Historical fragmentation of islands and genetic drift in populations of Galápagos lava lizards (Microlophus albemarlensis complex). Molecular Ecology 17: 1224–1237. DOI: 10.1111/j.1365-294X.2007.03658.x
Appendix 1: Locality data used to create the distribution map of Microlophus indefatigabilis 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 Borrero | iNaturalist; photo examined |
| Ecuador | Galápagos | Baltra airport | Kizirian 2003 |
| Ecuador | Galápagos | Black Cove | Kizirian 2003 |
| Ecuador | Galápagos | Camino a Cerro Dragon | Benavides et al. 2009 |
| Ecuador | Galápagos | Canal de Itabaca, N | Arteaga et al. 2019 |
| Ecuador | Galápagos | Canal Itabaca, S | Benavides et al. 2009 |
| Ecuador | Galápagos | Cerro Colorado | Benavides et al. 2009 |
| Ecuador | Galápagos | Cerro Gallina, environs of | Benavides et al. 2009 |
| Ecuador | Galápagos | Dahpne Major | Benavides et al. 2009 |
| Ecuador | Galápagos | Edén islet | Benavides et al. 2009 |
| Ecuador | Galápagos | El Chato, 6 km SW of | Arteaga et al. 2019 |
| Ecuador | Galápagos | El Garrapatero | Arteaga et al. 2019 |
| Ecuador | Galápagos | El Garrapatero, 2 km SW of | iNaturalist; photo examined |
| Ecuador | Galápagos | Estación Charles Darwin | Arteaga et al. 2019 |
| Ecuador | Galápagos | FAE | iNaturalist; photo examined |
| Ecuador | Galápagos | Guy Fawkes Norte | Jordan & Snell 2008 |
| Ecuador | Galápagos | Guy Fawkes Sur | Jordan & Snell 2008 |
| Ecuador | Galápagos | Islote Caamaño | Arteaga et al. 2019 |
| Ecuador | Galápagos | Islote Mosquera | Arteaga et al. 2019 |
| Ecuador | Galápagos | Islote Plaza Norte | Benavides et al. 2009 |
| Ecuador | Galápagos | Islote Punta Bowditch Norte | Jordan & Snell 2008 |
| Ecuador | Galápagos | Islote Punta Bowditch Sur | Benavides et al. 2009 |
| Ecuador | Galápagos | Itabaca, 11.2 km SW of | iNaturalist; photo examined |
| Ecuador | Galápagos | Itabaca, 13.3 km SW of | Tanner and Perry 2007 |
| Ecuador | Galápagos | Itabaca, 16.4 km SW of | Arteaga et al. 2019 |
| Ecuador | Galápagos | Itabaca, 3.7 km SW of | Tanner and Perry 2007 |
| Ecuador | Galápagos | Itabaca, 7.5 km SW of | Tanner and Perry 2007 |
| Ecuador | Galápagos | La Ratonera, 500 m E of | Arteaga et al. 2019 |
| Ecuador | Galápagos | Las Bachas | Arteaga et al. 2019 |
| Ecuador | Galápagos | Las Grietas | Topical Herping |
| Ecuador | Galápagos | Playa de los Alemanes | Arteaga et al. 2019 |
| Ecuador | Galápagos | Plaza Sur islet | Jordan et al. 2005 |
| Ecuador | Galápagos | Puerto Ayora, 4 km N of | Tanner and Perry 2007 |
| Ecuador | Galápagos | Puerto Ayora, calle N10 | Arteaga et al. 2019 |
| Ecuador | Galápagos | Puerto Ayora, Crossman Hotel | Arteaga et al. 2019 |
| Ecuador | Galápagos | Puerto Ayora, environs of | Arteaga et al. 2019 |
| Ecuador | Galápagos | Punta Roca Fuerte | Fritts and Fritts 1982 |
| Ecuador | Galápagos | Road to Baltra airport | iNaturalist; photo examined |
| Ecuador | Galápagos | Santa Cruz in front of Venecia Islet | Jordan & Snell 2008 |
| Ecuador | Galápagos | Seymour Norte | Benavides et al. 2009 |
| Ecuador | Galápagos | Small Islet 2.3 km NE of Guy Fawkes | Jordan & Snell 2008 |
| Ecuador | Galápagos | Small Islet 2.5 km NE of Guy Fawkes | Jordan & Snell 2008 |
| Ecuador | Galápagos | Tortuga Bay | Arteaga et al. 2019 |
| Ecuador | Galápagos | Tortuga Bay trail | Arteaga et al. 2019 |
| Ecuador | Galápagos | Unnamed beach SE Santa Cruz | iNaturalist; photo examined |
| Ecuador | Galápagos | Venecia Islet | Benavides et al. 2009 |
| Ecuador | Galápagos | Venecia islet, 1 km W of | Benavides et al. 2009 |