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Sand Sticklizard (Pholidobolus prefrontalis)
Reptiles of Ecuador | Sauria | Gymnophthalmidae | Pholidobolus | Pholidobolus prefrontalis
English common name: Sand Sticklizard.
Spanish common name: Cuilanpalo de arena.
Recognition: ♂♂ 14.3 cmMaximum distance from the snout to the tip of the tail. Snout–vent length=5.7 cm. ♀♀ 16.1 cmMaximum distance from the snout to the tip of the tail. Snout–vent length=6.3 cm..1,2 Sticklizards differ from other lizards by having short but well-developed limbs, overlapping striated sub-hexagonal dorsal scales, and a brownish dorsal pattern with longitudinal stripes.1,3 The presence of six-sided finely wrinkled dorsal scales distinguishes Pholidobolus from other co-occurring small brownish lizards such as those in the genera Andinosaura and Anadia.4 The Sand Sticklizard (P. prefrontalis) co-occurs and can be confused with P. affinis, from which it differs by having two, instead of three, supraocular scales. Pholidobolus macbrydei differs from P. prefrontalis by lacking prefrontal scales and because males of the former have a red lateral stripe (prefrontal scales present and red stripe absent in P. prefrontalis).1,3 There is no major sexual dimorphism in P. prefrontalis: males and females are similar in size and coloration.

Figure 1: Individuals of Pholidobolus prefrontalis from Tixán, Chimborazo province, Ecuador..
Natural history: Locally frequentRecorded weekly in densities below five individuals per locality.. Pholidobolus prefrontalis inhabits human-modified environments such as pastures and crops as well as open areas at the edge of seasonally dry shrublands and high evergreen forests.1,2 Sand Sticklizards are diurnal, terrestrial, and are usually found in xeric environments.1 During sunny days, they forage and bask on soil, grass, rocks, Agave plants, and bromeliads. When not active, individuals hide under rocks.1,2 When threatened, they take refuge under rocks, in the axils of Agave leaves, or among vegetation; if handled, they may shed the tail or bite.1,2 Almost nothing is known about the reproductive habits of this species, but Pholidobolus lizards in general usually deposit to two eggs per clutch.1 During mating, males typically approach the female from the side, licking her body; if the female is receptive, the male bites her neck, surrounds her dorsal region with the hind limbs, and copulates; if the female is not receptive, she drags her body and twists her tail.1 Communal nests of up to 12 eggs of P. prefrontalis have been found under rock piles.1
Conservation: Vulnerable Considered to be facing a high risk of extinction in the mid-term future.. Pholidobolus prefrontalis is proposed to be included this category, instead of Least Concern,5 following IUCN criteria.6 The species’ extent of occurrence is small (~1,778 km2; Fig. 2) and despite being adapted to human-modified areas, its range of distribution is severely fragmented and continues to decline in extent and quality due to the expansion of the agricultural frontier. Based on maps of Ecuador’s vegetation cover published in 2012,7 the majority (~75%) of the species’ potential distribution is now devoid of native vegetation. Also, most records of this species from Azuay and Cañar provinces have now been shown to be misidentifications.8 Thus, P. prefrontalis is not known to occur in any protected areas. However, there is no current information on the population trend of the species to determine whether its numbers are declining.5
Distribution: Pholidobolus prefrontalis is endemic to an estimated 1,778 km2 area in the inter-Andean valleys of south-central Ecuador, in the provinces Chimborazo and Bolívar. The species occurs at elevations between 2372 and 3143 m (Fig. 2).

Figure 2: Distribution of Pholidobolus prefrontalis in Ecuador. The star corresponds to the type locality: 4.9 km S Tixán. See Appendix 1 for a complete list of the presence localities included in the map.
Etymology: The generic name Pholidobolus, which comes from the Greek words pholidos (meaning “scale”) and bolos (meaning “lump”),9 probably refers to the imbricated or mounted scales that are characteristic of the genus. The specific epithet prefrontalis refers to the prominent prefrontal scales present in individuals of this species.1
See it in the wild: Sand Sticklizards can easily be observed in areas having remnants of native shrubland vegetation nearby towns such as Alausí and Tixán. Lizards of this species can be found by searching under rocks and logs in pastures nearby remnants of native vegetation or simply by looking along stone walls and living fences during sunny days.
Author: Amanda QuezadaaAffiliation: Tropical Herping (TH), Quito, Ecuador.,bAffiliation: Laboratorio de Herpetología, Universidad del Azuay, Cuenca, Ecuador.
Editor: Alejandro ArteagacAffiliation: Biodiversity Field Lab, Khamai Foundation, Quito, Ecuador.
Photographer: Jose VieiraaAffiliation: Tropical Herping (TH), Quito, Ecuador.,dAffiliation: ExSitu, Quito, Ecuador.
How to cite? Quezada A (2021) Sand Sticklizard (Pholidobolus prefrontalis). 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. DOI: 10.47051/MOJQ2003
Literature cited:
- Montanucci RR (1973) Systematics and evolution of the Andean Lizard genus Pholidobolus (Sauria: Teiidae). Miscellaneous Publications of the Museum of Natural History, University of Kansas 59: 1–52.
- Field notes, Reptiles of Ecuador book project.
- Torres-Carvajal O, Venegas P, Lobos SE, Mafla-Endara P, Sales Nunes PM (2014) A new species of Pholidobolus (Squamata: Gymnophthalmidae) from the Andes of southern Ecuador. Amphibian & Reptile Conservation 8: 76–88.
- Peters JA, Donoso-Barros R (1970) Catalogue of the Neotropical Squamata: part II, lizards and amphisbaenians. Bulletin of the United States National Museum, Washington, D.C., 293 pp.
- Cisneros-Heredia DF (2016) Pholidobolus prefrontalis. The IUCN red list of threatened species. Available from: www.iucnredlist.org. DOI: 10.2305/IUCN.UK.2016-1.RLTS.T48283483A48283487.en
- IUCN (2001) IUCN Red List categories and criteria: Version 3.1. IUCN Species Survival Commission, Gland and Cambridge, 30 pp.
- MAE (2012) Línea base de deforestación del Ecuador continental. Ministerio del Ambiente del Ecuador, Quito, 30 pp.
- Parra V, Sales Nunes PM, Torres-Carvajal O (2020) Systematics of Pholidobolus lizards (Squamata, Gymnophthalmidae) from southern Ecuador, with descriptions of four new species. ZooKeys 954: 109–156. DOI: 10.3897/zookeys.954.50667
- Brown RW (1956) Composition of scientific words. Smithsonian Books, Washington D.C., 882 pp.
Appendix 1: Locality data used to create the distribution map of Pholidobolus prefrontalis in Ecuador (Fig. 2). Go to the section on symbols and abbreviations for a list of acronyms used. Asterisk (*) indicates type locality.
Country | Province | Locality | Source |
Ecuador | Bolívar | Guaranda | Montanucci 1973 |
Ecuador | Bolívar | Guaranda, 8.3 km S of | Hillis 1985 |
Ecuador | Bolívar | San Jose del Chimbo | Montanucci 1973 |
Ecuador | Bolívar | Vicity of La Moya | This work |
Ecuador | Chimborazo | Alausí | Hurtado-Gómez et al. 2018 |
Ecuador | Chimborazo | Tixán | Venegas et al. 2016 |
Ecuador | Chimborazo | Tixán, 1.3 km SW of | MZUTI 5391 |
Ecuador | Chimborazo | Tixán, 4.9 km S of* | Montanucci 1973 |