Seven-lined Ground Snake (Atractus gaigeae)

Reptiles of Ecuador | Serpentes | Colubridae | Atractus gaigeae

English common names: Seven-lined Ground Snake, Gaige’s Ground Snake.

Spanish common names: Tierrera de siete líneas, tierrera de Gaige.

Recognition: ♂♂ 30 cmMaximum distance from the snout to the tip of the tail. Snout–vent length=26.6 cm. ♀♀ 33.8 cmMaximum distance from the snout to the tip of the tail. Snout–vent length=31.2 cm..¹ Atractus gaigeae differs from other snakes in its area of distribution by having a round head similar in width to the neck, small eyes, an incomplete light nape band, and a brown dorsum with five longitudinal dark lines enclosing a series of dark spots.^1,2 Atractus gaigeae is unique among its co-occurring congeners in having a cream-colored belly with two dark longitudinal lines, one along each margin (seven lines counting the dorsal lines).^2,3 This species is often confused with A. collaris, but this other species lacks a blackish vertebral line and has fewer than 200 and 184 ventral scales in females and males, respectively (more than 200 and 184 in females and males in A. gaigeae).¹

Figure showing an adult male of Atractus gaigeae

Figure 1: Adult male of Atractus gaigeae from Yuralpa, Napo province, Ecuador.

Natural history: Atractus gaigeae is a rarely seen semi-fossorial snake about which very little is known. Most of the records of this species are from pristine lowland and foothill evergreen forest areas. Seven-lined Ground Snakes feed on earthworms,⁴ but other aspects of their habits or behavior are unknown. One individual was seen crossing a dirt road during the early morning.⁵ In general, ground snakes can be found moving on the leaf-litter at night or inactive under rocks and logs during the day.⁵ Snakes of this genus are harmless and always try to flee upon detecting a threat.⁵

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Conservation: Least Concern Believed to be safe from extinction given current circumstances..⁶ Atractus gaigeae is listed in this category because current information suggests that the species is distributed over a wide (greater than 50,000 km²) area that retains the majority of its original forest cover. Approximately 85% of the species’ potential area of distribution (Fig. 2) still holds continuous rainforest habitat.⁷ However, some populations are probably threatened by deforestation caused by the expansion of the agricultural frontier. Additionally, the difficulty in locating individuals of this species in the field makes it challenging to understand its populations status.⁶

Distribution: Atractus gaigeae is native to an area of approximately 46,948 km² in the upper Amazon basin and adjacent foothills of the Andes in Ecuador (Fig. 2). The species probably also occurs in neighboring Colombia and Perú.

Figure 2: Distribution of Atractus gaigeae in Ecuador. The star corresponds to the approximate type locality: Santiago-Zamora. See Appendix 1 for a complete list of the presence localities included in the map.

Etymology: The name Atractus, which is a latinization of the Greek word άτρακτος (=spindle),^8–10 probably refers to the fact that snakes of this genus have a uniform width throughout the body and a narrow tail, resembling an antique spindle used to spin fibers. The specific epithet gaigeae honors American herpetologist Helen Thompson Gaige, best known for her role as curator of amphibians at the Museum of Zoology at the University of Michigan.²

See it in the wild: Atractus gaigeae is one of the rarest ground snakes in the Amazon rainforest of Ecuador. There are only four localities where the species has been observed more than once and only one of them is not remote: Jatun Sacha Biological Reserve, with five confirmed observations. Seven-lined Ground Snakes may be located by scanning the forest floor and leaf-litter along trails at night or by looking under rocks and logs in pastures near the forest border.

Author: Duvan Zambrano^aAffiliation: Universidad del Tolima, Ibagué, Colombia.

Editor: Alejandro Arteaga^bAffiliation: Khamai Foundation, Quito, Ecuador.

Photographer: Sebastián Di Doménico^cAffiliation: Keeping Nature, Bogotá, Colombia.

How to cite? Zambrano D (2024) Seven-lined Ground Snake (Atractus gaigeae). 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/BRJL5523

Literature cited:

Passos P, Prudente A, Ramos LO, Caicedo-Portilla JR, Lynch JD (2018) Species delimitations in the Atractus collaris complex (Serpentes: Dipsadidae). Zootaxa 4392: 491–520. DOI: 10.11646/zootaxa.4392.3.4
Savage JM (1955) Descriptions of new colubrid snakes, genus Atractus, from Ecuador. Proceedings of the Biological Society of Washington 68: 11–20.
Savage JM (1960) A revision of the Ecuadorian snakes of the Colubrid genus Atractus. Miscellaneous Publications, Museum of Zoology, Univesity of Michigan 112: 1–184.
Rocha JC (2019) Influência de fatores ambientais e a relação entre os padrões de diversidade beta taxonômica e diversidade beta funcional de serpentes neotropicais. MSc thesis, Florianópolis, Universidade Federal de Santa Catarina, 119 pp.
Field notes, Reptiles of Ecuador book project.
Cisneros-Heredia D, Yánez-Muñoz M, Reyes-Puig C (2016) Atractus gaigeae. The IUCN Red List of threatened species. Available from: www.iucnredlist.org. DOI: 10.2305/IUCN.UK.2017-2.RLTS.T50951092A50951097.en.
MAE (2012) Línea base de deforestación del Ecuador continental. Ministerio del Ambiente del Ecuador, Quito, 30 pp.
Woodward SP, Tate R (1830) A manual of the Mollusca: being a treatise on recent and fossil shells. C. Lockwood and Company, London, 750 pp.
Beekes R (2010) Etymological dictionary of Greek. Brill, Boston, 1808 pp.
Duponchel P, Chevrolat L (1849) Atractus. In: d’Orbigny CD (Ed) Dictionnaire universel d’histoire naturelle. MM. Renard, Martinet et Cie., Paris, 312.

Appendix 1: Locality data used to create the distribution map of Atractus gaigeae 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	Morona Santiago	Achuentz	Passos et al. 2018
Ecuador	Morona Santiago	Centro Shuar Kiim	Passos et al. 2018
Ecuador	Morona Santiago	Cusuime	Ortega-Andrade 2010
Ecuador	Morona Santiago	Macas	Arteaga et al. 2017
Ecuador	Morona Santiago	Macuma	Passos et al. 2018
Ecuador	Morona Santiago	Santiago de Tiwintza*	Savage 1955
Ecuador	Morona Santiago	Taisha	Photo by Jorge Valencia
Ecuador	Napo	Boca del Río Coca	Passos et al. 2018
Ecuador	Napo	Centro Palmeras	iNaturalist
Ecuador	Napo	Estación Biológica Jatun Sacha	Vigle 2008
Ecuador	Napo	Gareno Lodge	This work
Ecuador	Napo	Tena, 1.7 km NE of	iNaturalist
Ecuador	Napo	Universidad Ikiam	iNaturalist
Ecuador	Napo	Yachana Reserve	Passos et al. 2018
Ecuador	Napo	Yuralpa	This work
Ecuador	Orellana	Comunidad Dicapare	Passos et al. 2018
Ecuador	Orellana	Loreto	Passos et al. 2018
Ecuador	Orellana	San José de Payamino	Maynard et al. 2016
Ecuador	Orellana	Pindo, bloque 64	Passos et al. 2018
Ecuador	Pastaza	Arajuno	Passos et al. 2018
Ecuador	Pastaza	Cabeceras del Río Bobonaza	Savage 1955
Ecuador	Pastaza	Camelon	MCZ R-29298
Ecuador	Pastaza	Campo K32	Passos et al. 2018
Ecuador	Pastaza	Campo Villano B	Passos et al. 2018
Ecuador	Pastaza	Canelos	Savage 1955
Ecuador	Pastaza	Chichirota	Savage 1955
Ecuador	Pastaza	Comunidad Tarangaro	Passos et al. 2018
Ecuador	Pastaza	Copataza	Passos et al. 2018
Ecuador	Pastaza	Kurintza	Ortega-Andrade 2010
Ecuador	Pastaza	Montalvo	Passos et al. 2018
Ecuador	Pastaza	Pozo Garza-1	Passos et al. 2018
Ecuador	Pastaza	Río Conambo, mouth of Río Shione	Passos et al. 2018
Ecuador	Pastaza	Río Conambo, near mouth of Río Romarizo	Passos et al. 2018
Ecuador	Pastaza	Río Rutuno	Passos et al. 2018
Ecuador	Pastaza	Río Villano	USNM 217628
Ecuador	Pastaza	Sarayacu	Savage 1955
Ecuador	Sucumbíos	Santa Elena	Passos et al. 2018