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Brown Forest-Racer (Dendrophidion brunneum)
Reptiles of Ecuador | Serpentes | Colubridae | Dendrophidion brunneum
English common name: Brown Forest-Racer.
Spanish common name: Corredora selvática café.
Recognition: ♂♂ 123 cmMaximum distance from the snout to the tip of the tail. Snout–vent length=70.0 cm. ♀♀ 136.9 cmMaximum distance from the snout to the tip of the tail. Snout–vent length=79.6 cm..1 Dendrophidion brunneum can be identified by having a dorsal coloration that varies from olive to pale greenish-brown, where the anterior zone is lighter than the posterior (Fig. 1).1,2 Some individuals have a uniformly olive, blue-green, or brown dorsal coloration.2,3 The head of adults is dark green or bluish, changing drastically in color as it approaches the neck.1 The supralabial scales are white and the tongue is black. This species can be distinguished from other Dendrophidion primarily based on coloration.1 Unlike D. graciliverpa and D. prolixum, this species lacks transverse dorsal bars.2 From D. clarkii, it differs by lacking a brown nuchal band and a reddish brown tail.4
Figure 1: Juvenile of Dendrophidion brunneum from Guayaquil, Guayas province, Ecuador.
Natural history: Dendrophidion brunneum is a terrestrial snake that inhabits old-growth to heavily disturbed seasonally dry forests and humid montane forests, usually in association with bodies of water.1,5 The species also tolerates disturbed areas such as montane forest patches intermixed with grasslands, coffee plantations, banana crops, and even peri-urban areas.1,5 Brown Forest-Racers are diurnal and more likely to be active during sunny days, with an increase peak of activity during the end of the rainy season (May–June).1 The majority of their activity occurs at ground level but individuals may occasionally be spotted on low vegetation.6 At night or during overcast days, they remain hidden in ground burrows, in cavities among roots, or beneath surface objects such as rocks and bricks.1,5 These snakes are active hunters of terrestrial Pristimantis rainfrogs,1,5 but also include lizards of the genus Stenocercus in their diet.1 The Forest-Racer, when cornered, subtly inflates its neck, opens the mouth aggressively, and strikes.1 Its tail is long, fragile, and breaks off easily when grabbed by a predator, enabling the escape and survival of the snake.1 There is an unpublished photographic record of a Monitor Tegu (Callopistes flavipunctatus) preying upon an individual of this species.5 The clutch size in D. brunneum consists of 4–7 eggs.1,7 Breeding is presumed to occur during the dry season.1,7
Conservation: Least Concern Believed to be safe from extinction given current circumstances..8 Dendrophidion brunneum is listed in this category primarily because the species’ wide distribution and presence in disturbed areas suggests no major population declines, although the proximity to these populated areas increases death events.8 The main threat to the long-term survival of some populations of D. brunneum is the continuing decline in the extent and quality of its habitat, mostly due to encroaching human activities such as agriculture, cattle grazing, wild fires, and the replacement of native vegetation with eucalyptus and pine trees. Brown Forest-Racers also suffer from traffic-related mortality and human persecution.5
Distribution: Dendrophidion brunneum is widely distributed along the Tumbesian lowlands and adjacent Andean foothills of northwestern Perú and western Ecuador (Fig. 2), with an isolated population in the mid-elevation montane forests of Pichincha and Imbabura provinces. Some snakes in this northern population were previously confused with D. bivittatus,9 but are morphologically more similar to D. brunneum.
Figure 2: Distribution of Dendrophidion brunneum in Ecuador. The star corresponds to the type locality: Guayaquil, Guayas province. See Appendix 1 for a complete list of the presence localities included in the map.
Etymology: The genus name Dendrophidion comes from the Greek words dendron (=tree) and ophidion (=small snake).10 The specific epithet brunneum (=brown in Latin)10 refers to the dorsal coloration of some individuals.
See it in the wild: The Brown Forest-Racer is not uncommon throughout the southern portion of its distribution in Ecuador. In Loja province, for example, Dendrophidion brunneum is one of the most frequently encountered diurnal snakes, with sightings occurring at a rate of about once every few days, particularly in rural areas having remnants of native vegetation. The racers are most easily spotted by walking along forest trails or small dirt roads during sunny mornings at the end of the rainy season (April–May).
Acknowledgments: Special thanks to Eduardo Zavala for finding the specimen of Dendrophidion brunneum photographed in this account.
Authors: Tatiana Molina-Moreno,aAffiliation: Departamento de Biología, Universidad de los Llanos, Villavicencio, Colombia. Andrés F. Aponte-Gutiérrez,bAffiliation: Grupo de Investigación en Ciencias de la Orinoquía, Universidad Nacional de Colombia sede Orinoquía, Arauca, Colombia.,cAffiliation: Fundación Biodiversa Colombia, Bogotá, Colombia. Danna Duque-Torres,dAffiliation: Grupo de Ornitología, Universidad Nacional de Colombia, Bogotá, Colombia. and Alejandro ArteagaeAffiliation: Tropical Herping (TH), Quito, Ecuador.
Photographer: Jose VieirafAffiliation: Tropical Herping (TH), Quito, Ecuador.,gAffiliation: ExSitu, Quito, Ecuador.
How to cite? Molina-Moreno T, Aponte-Gutierrez AF, Duque-Torres D, Arteaga A (2024) Brown Forest-Racer (Dendrophidion brunneum). 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/FFVJ6432
Literature cited:
- Cadle JE (2010) Systematics, natural history, and hemipenial morphology of Dendrophidion brunneum (Günther) (Serpentes: Colubridae), a poorly known snake from the Andes of Ecuador and Peru. Zootaxa 2433: 1–24. DOI: 10.11646/zootaxa.2433.1.1
- Cadle JE (2012) Systematics of the Neotropical snake Dendrophidion percarinatum (Serpentes: Colubridae), with descriptions of two new species from western Colombia and Ecuador and supplementary data on Dendrophidion brunneum. Bulletin of the Museum of Comparative Zoology 160: 259–344. DOI: 10.3099/0027-4100-160.6.259
- Cruz-García K, Barreno M, Cuadrado S, Moretta-Urdiales MDM, Molina-Moreira N, Salas JA, Torres-Domínguez A, Narváez AE (2023) Amphibians and reptiles of Isla Santay (Durán, Ecuador). Check List 19: 347–369. DOI: 10.15560/19.3.347
- Cadle JE, Savage JM (2012) Systematics of the Dendrophidion nuchale complex (Serpentes: Colubridae) with the description of a new species from Central America. Zootaxa 3513: 1–50. DOI: 10.11646/zootaxa.3513.1.1
- Field notes, Reptiles of Ecuador book project.
- Photo by Fernando García.
- Kuch U (1993) Dendrophidion brunneum: reproduction and size. Herpetological Review 24: 106.
- Yánez-Muñoz M, Cisneros-Heredia DF, Brito J (2022) Dendrophidion brunneum. The IUCN Red List of threatened species. Available from: www.iucnredlist.org. DOI: 10.2305/IUCN.UK.2022-1.RLTS.T203285A217779727.en
- Valencia J, Garzón K (2007) First record of the snake Dendrophidion bivittatus (Duméril, Bibron & Duméril, 1854) and taxonomic remarks on the genus in Ecuador. Herpetozoa 20: 86–88.
- 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 Dendrophidion brunneum 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 | Azuay | Girón, 10 km SW of | Cadle 2010 |
| Ecuador | Azuay | Poetate | Reptiles of Ecuador book database |
| Ecuador | Azuay | Puente de Chaucha | Fausto Siavichay |
| Ecuador | Azuay | Reserva Biológica Yunguilla | Photo by Jorge Luis Romero |
| Ecuador | Azuay | Susudel | Photo by Jorge Luis Romero |
| Ecuador | Azuay | Valle de Yunguilla | Almendáriz & Brito 2011 |
| Ecuador | Azuay | Yunguilla | Reptiles of Ecuador book database |
| Ecuador | Chimborazo | Alausí | Reptiles of Ecuador book database |
| Ecuador | Chimborazo | Río Chiguancay | Cadle 2012 |
| Ecuador | Chimborazo | Sacramento | Cadle 2010 |
| Ecuador | Cotopaxi | La Maná | Cadle 2010 |
| Ecuador | El Oro | Bosque Petrificado de Puyango | Acosta 2014 |
| Ecuador | El Oro | Chepel | Garzón-Santomaro et al. 2019 |
| Ecuador | El Oro | Portovelo | Cadle 2012 |
| Ecuador | El Oro | Reserva Biológica Buenaventura | Cogălniceanu et al. 2015 |
| Ecuador | El Oro | Zaruma | Cadle 2012 |
| Ecuador | El Oro | Zaruma–Huertas | iNaturalist; photo examined |
| Ecuador | Guayas | Capeira | Photo by Eduardo Zavala |
| Ecuador | Guayas | Daule, 10 km S of | Cadle 2012 |
| Ecuador | Guayas | Durán, 18 km E of | Cadle 2012 |
| Ecuador | Guayas | Guayaquil, Fuerte Huancavilca | iNaturalist; photo examined |
| Ecuador | Guayas | Guayaquil* | Günther 1858 |
| Ecuador | Guayas | Isla Santay | Cruz-García et al. 2023 |
| Ecuador | Guayas | Milagro | USNM 237061; VertNet |
| Ecuador | Guayas | Venecia | iNaturalist; photo examined |
| Ecuador | Imbabura | Chalguayacu | Rodríguez-Guerra & Guerra-Correa 2020 |
| Ecuador | Imbabura | Ibarra | Cadle 2012 |
| Ecuador | Imbabura | Intag | Cadle 2010 |
| Ecuador | Imbabura | Ríolindo Coffee Farm | Photo by Kevin Narum |
| Ecuador | Imbabura | San Antonio | Rodríguez-Guerra & Guerra-Correa 2020 |
| Ecuador | Imbabura | Selva Alegre | Valencia & Garzón 2007 |
| Ecuador | Loja | Alamor | Cadle 2012 |
| Ecuador | Loja | Camposanto Los Rosales | Photo by Rita Hidalgo |
| Ecuador | Loja | Celén | Rodríguez-Guerra & Guerra-Correa 2020 |
| Ecuador | Loja | Chaguarpamba | Reptiles of Ecuador book database |
| Ecuador | Loja | Chivato | iNaturalist; photo examined |
| Ecuador | Loja | El Sauco | Torres-Carvajal et al. 2019 |
| Ecuador | Loja | Finca Sagrada | iNaturalist; photo examined |
| Ecuador | Loja | Hacienda Masaca | Cadle 2012 |
| Ecuador | Loja | Loja | Photo by Darwin Núñez |
| Ecuador | Loja | Loja, 7.3 km N of | Cadle 2010 |
| Ecuador | Loja | Loja, calle Bruselas | Reptiles of Ecuador book database |
| Ecuador | Loja | Quebrada Buenavista | Reptiles of Ecuador book database |
| Ecuador | Loja | Quinara, 3.5 km W of | iNaturalist; photo examined |
| Ecuador | Loja | Quinara, 4.5 km SE of | MUTPL 441; GBIF |
| Ecuador | Loja | Río Cochurco | Reptiles of Ecuador book database |
| Ecuador | Loja | Rumishitana | Rodríguez-Guerra & Guerra-Correa 2020 |
| Ecuador | Loja | San Pedro de la Bendita | MUTPL 421; GBIF |
| Ecuador | Los Ríos | Bosque Protector Pedro Franco Dávila | Cruz & Sánchez 2016 |
| Ecuador | Los Ríos | Finca Playa Grande | Cadle 2012 |
| Ecuador | Los Ríos | Hacienda Los Canchones | iNaturalist; photo examined |
| Ecuador | Los Ríos | Quevedo, 20 km NE of | Cadle 2012 |
| Ecuador | Manabí | Chone, 3 km N of | iNaturalist; photo examined |
| Ecuador | Manabí | El Guayacán | iNaturalist; photo examined |
| Ecuador | Manabí | Eloy Alfaro | Photo by Redgy Vera |
| Ecuador | Manabí | Maicito | MHNG 1363.036; collection database |
| Ecuador | Manabí | Manta | iNaturalist; photo examined |
| Ecuador | Manabí | N of Pedernales | Photo by Konrad Mebert |
| Ecuador | Manabí | Pedernales | Reptiles of Ecuador book database |
| Ecuador | Manabí | Puerto Rico | Torres-Carvajal et al. 2019 |
| Ecuador | Manabí | Refugio de Vida Silvestre Pacoche | iNaturalist; photo examined |
| Ecuador | Manabí | Salango | iNaturalist; photo examined |
| Ecuador | Manabí | Santa Rosa | iNaturalist; photo examined |
| Ecuador | Manabí | Sesme | iNaturalist; photo examined |
| Ecuador | Pichincha | Dos Puentes | Photo by Axel Marchelie |
| Ecuador | Pichincha | Km 32 Calacalí–Los Bancos | Valencia et al. 2017 |
| Ecuador | Pichincha | Nanegalito | Photo by Andrew Cecil |
| Ecuador | Pichincha | Santa Marianita | iNaturalist; photo examined |
| Ecuador | Pichincha | Tandayapa | Photo by Jacobo Quero |
| Ecuador | Pichincha | Tulipe | Reptiles of Ecuador book database |
| Ecuador | Santa Elena | Barcelona | iNaturalist; photo examined |
| Ecuador | Santa Elena | Olón, 3 km E of | Cadle 2012 |
| Ecuador | Zamora Chinchipe | Bella Vista | iNaturalist; photo examined |
| Ecuador | Zamora Chinchipe | Río Isimanchi | iNaturalist; photo examined |
| Ecuador | Zamora Chinchipe | Zumba–Pucubamba | Reptiles of Ecuador book database |
| Perú | Amazonas | Chachapoyas | Cadle 2010 |
| Perú | Cajamarca | Asunción | Cadle 2010 |
| Perú | Cajamarca | El Prado | MVZ 119329; VertNet |
| Perú | Cajamarca | Río Zaña study site | Cadle 2010 |
| Perú | La Libertad | Cascas | Cadle 2010 |
| Perú | Piura | Canchaque, 15 km E of | Cadle 2010 |
| Perú | Piura | Immediate vicinity of Ayabaca | Cadle 2010 |
| Perú | Piura | Morropon | Cadle 2010 |
| Perú | Piura | Quebrada Cimarrón | Cadle 2010 |