Published April 22, 2024. Open access.

Gallery ❯

Glossy Racer (Drymoluber dichrous)

Reptiles of Ecuador | Serpentes | Colubridae | Drymoluber dichrous

English common names: Glossy Racer, Northern Woodland Racer.

Spanish common names: Serpiente corredora lustrosa, serpiente corredora brillante.

Recognition: ♂♂ 130 cmMaximum distance from the snout to the tip of the tail. Snout–vent length=95.2 cm. ♀♀ 103.2 cmMaximum distance from the snout to the tip of the tail. Snout–vent length=74.4 cm..1 Drymoluber dichrous can be recognized by having smooth dorsals arranged in 15 rows at mid-body and a unique coloration that changes throughout the snake’s lifespan. Juveniles have a dorsal pattern consisting of broad rich reddish brown bands separated from each other by narrow white or cream bands, with a bright yellow, orange, or red nape band and snout.15 Adults are uniformly dark olive brown or black, with a dark postocular stripe constrasting heavily with the pale supralabials (Fig. 1).15 The juveniles are unlikely to be confused, but the the adults resemble the coloration of Erythrolamprus reginae, from which they differ by lacking black longitudinal stripes on the tail.2,3

Figure showing variation among individuals of Drymoluber dichrous

Figure 1: Individuals of Drymoluber dichrous: Leticia, Amazonas department, Colombia (); Gareno, Napo province, Ecuador (). j=juvenile.

Natural history: Drymoluber dichrous is a terrestrial to semi-arboreal snake that inhabits lowland terra-firme rainforests and floodplain forests, occurring also in forest-edge situations and along roadsides.16 Glossy Racers are active on the forest floor during the daytime.3 At night, they typically roost coiled on understory vegetation 30–250 cm above the ground,3,6 but may occasionally remain hidden in the leaf-litter.4 Glossy Racers are active predators characterized by their speed in catching and devouring prey.4 Their diet consists of lizards (including Ameiva ameiva,7 Arthrosaura reticulata,7 Iphisa brunopereira,4 Potamites ecpleopus,2 Gonatodes humeralis,1 and Anolis fuscoauratus8), lizard eggs,4 snakes (Mastigodryas and Oxybelis),9,10 birds, and amphibians (Pristimantis and Leptodactylus).14 The Glossy Racer, when cornered, adopts an S-shape posture, opens the mouth aggressively, and strikes.4 There is a recorded instance of predation on a member of this species by the tarantula Theraphosa blondi.11 The clutch size in D. dichrous consist of 1–6 eggs, with reproduction taking place throughout the year.1,4,9,12

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Conservation: Least Concern Believed to be safe from extinction given current circumstances..13 Drymoluber dichrous is listed in this category because the species is widely distributed, occurs in many protected areas (at least 10 in Ecuador), and is considered to be facing no major immediate threats of extinction.13 In addition, it is presumed that that populations of D. dichrous are stable and largely unfragmented.13 However, this species, a strict forest dweller, is under constant threat due to large-scaled deforestation driven by agricultural and urban expansion.

Distribution: Drymoluber dichrous occurs throughout the Amazonian lowlands and adjacent slopes of the Andes in Bolivia, Brazil, Colombia, Ecuador (Fig. 2), French Guiana, Guyana, Peru, Suriname, and Venezuela. It also occurs in the Atlantic Forest of Brazil.

Distribution of Drymoluber dichrous in Ecuador

Figure 2: Distribution of Drymoluber dichrous in Ecuador. See Appendix 1 for a complete list of the presence localities included in the map.

Etymology: The genus name Drymoluber is an amalgamation the genera Drymobius and Coluber, since it shares characteristics of both groups.14 The specific epithet dichrous is a Greek word meaning “two skins” and probably refers to the stark contrast between the pale ventral and dark dorsal coloration in adults.15

See it in the wild: Drymoluber dichrous is considered an uncommon species in Ecuador, with no more than 1–2 individuals recorded per month at any given locality. Prime areas for this species include Puyo and Yasuní Scientific Station, where these snakes are most easily detected by sampling understory vegetation along forest trails at night.

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: Sebastián Di DoménicofAffiliation: Keeping Nature, Bogotá, Colombia.

How to cite? Molina-Moreno T, Aponte-Gutierrez AF, Duque-Torres D, Arteaga A (2024) Glossy Racer (Drymoluber dichrous). In: Arteaga A, Bustamante L, Vieira J (Eds) Reptiles of Ecuador: Life in the middle of the world. Available from: DOI: 10.47051/GTEN4843

Literature cited:

  1. Dixon JR, Soini P (1986) The reptiles of the upper Amazon Basin, Iquitos region, Peru. Milwaukee Public Museum, Milwaukee, 154 pp.
  2. Duellman WE (1978) The biology of an equatorial herpetofauna in Amazonian Ecuador. Publications of the Museum of Natural History, University of Kansas 65: 1–352.
  3. Duellman WE (2005) Cusco amazónico: the lives of amphibians and reptiles in an Amazonian rainforest. Cornell University Press, Ithaca, 433 pp.
  4. Martins M, Oliveira ME (1998) Natural history of snakes in forests of the Manaus region, Central Amazonia, Brazil. Herpetological Natural History 6: 78–150.
  5. Cunha OR, Nascimento FP (1978) Ofídios da Amazônia. X. As cobras da região leste do Pará. Papéis Avulsos Museu Paraense Emílio Goeldi 31: 1–218.
  6. Field notes, Reptiles of Ecuador book project.
  7. Avila-Pires TCS (1995) Lizards of Brazilian Amazonia (Reptilia: Squamata). Zoologische Verhandelingen 299: 1–706.
  8. Veríssimo D, de Freitas MA, Rosa GM (2012) Drymoluber dichrous (Northern Woodland Racer) and Anolis fuscoauratus (Slender Anole): predation. Herpetological Bulletin 120: 36–38.
  9. dos Santos-Costa MC, Maschio GF, da Costa Prudente AL (2015) Natural history of snakes from Floresta Nacional de Caxiuanã, eastern Amazonia, Brazil. Herpetology Notes 8: 69–98.
  10. Borges-Nojosa DM, Lima DC (2001) Dieta de Drymoluber dichrous (Peters, 1863) dos Brejos de altitude do Estado do Ceará, Brasil (Serpentes, Colubridae). Boletin do Museu Nacional Río de Janeiro 468: 1–5.
  11. Bilce TM, Monteiro LB, Coêlho TA, De Souza DC (2021). Predation of the snake Drymoluber dichrous (Peters, 1863) (Serpentes: Colubridae) by the spider Theraphosa blondi (Latreille, 1804) (Araneae: Theraphosidae) in the Brazilian Amazon. Herpetology Notes 14: 239–241.
  12. Fitch H (1970) Reproductive cycles in lizards and snakes. Museum of Natural History, University of Kansas, Lawrence, 247 pp.
  13. Rivas G, Gutiérrez-Cárdenas P, Caicedo J (2019) Drymoluber dichrous. The IUCN Red List of threatened species. Available from: DOI: 10.2305/IUCN.UK.2019-2.RLTS.T44580218A44580227.en
  14. Uetz P, Freed P, Hošek J (2021) The reptile database. Available from:
  15. Caldeira-Costa H; Ribeiro Moura M, Neves Feio R (2013) Taxonomic revision of Drymoluber Amaral, 1930 (Serpentes: Colubridae). Zootaxa 3716: 349–394. DOI: 10.11646/zootaxa.3716.3.3

Appendix 1: Locality data used to create the distribution map of Drymoluber dichrous in Ecuador (Fig. 2). Go to the section on symbols and abbreviations for a list of acronyms used.

ColombiaCaquetáTres EsquinasMCZ-65387; VertNet
ColombiaCaucaPuerto BelloCalderón et al. 2023
ColombiaPutumayoCentro Experimental AmazónicoBetancourth-Cundar & Gutiérrez-Zamora 2010
ColombiaPutumayoGeneral FarfánYPM 007786; GBIF
ColombiaPutumayoLa GaitanaiNaturalist; photo examined
ColombiaPutumayoPuerto LeguizamoNogueira et al. 2019
ColombiaPutumayoRío Caquetá, vereda ZarsalCalderón et al. 2023
ColombiaPutumayoRío CaucaNogueira et al. 2019
ColombiaPutumayoVereda Las AcaciasiNaturalist; photo examined
EcuadorMorona SantiagoArapicosCosta et al. 2013
EcuadorMorona SantiagoCentro KiimNogueira et al. 2019
EcuadorMorona SantiagoComunidad AmazonasiNaturalist; photo examined
EcuadorMorona SantiagoHuasagaMCZ R-36965; VertNet
EcuadorMorona SantiagoLas ChontasNogueira et al. 2019
EcuadorMorona SantiagoMacasAMNH 28830; examined
EcuadorMorona SantiagoMacuma, environs ofiNaturalist; photo examined
EcuadorMorona SantiagoNormandíaAMNH 35927; examined
EcuadorMorona SantiagoRío LlushiñoNogueira et al. 2019
EcuadorMorona SantiagoRío NapinazaNogueira et al. 2019
EcuadorMorona SantiagoSucúaUSNM 283952; VertNet
EcuadorMorona SantiagoTrail between Chiguaza–MacumaCosta et al. 2013
EcuadorMorona SantiagoTuteganosaCosta 2010
EcuadorNapoBoca del Río PiatúaNogueira et al. 2019
EcuadorNapoBosque Protector Selva VivaiNaturalist; photo examined
EcuadorNapoEl BombónKU 121882; VertNet
EcuadorNapoJatun Sacha Biological ReserveNogueira et al. 2019
EcuadorNapoPayamino, 2 km SW ofNogueira et al. 2019
EcuadorNapoPuerto Barantilla, 2 km SE ofiNaturalist; photo examined
EcuadorNapoPuerto MisahuallíRMNH-RENA50972; GBIF
EcuadorNapoSan RamónCosta et al. 2013
EcuadorNapoTenaNogueira et al. 2019
EcuadorNapoUniversidad IkiamiNaturalist; photo examined
EcuadorNapoWild Sumaco Wildlife SanctuaryCamper et al. 2021
EcuadorNapoYachana ReserveWhitworth & Beirne 2011
EcuadorNapoZoo el ArcaPhoto by Diego Piñán
EcuadorOrellanaApaikaNogueira et al. 2019
EcuadorOrellanaÁvilaTorres-Carvajal et al. 2019
EcuadorOrellanaBloque 16Nogueira et al. 2019
EcuadorOrellanaBoyopare, 8 km SE ofNogueira et al. 2019
EcuadorOrellanaEl CocaMHNG 2220.099; collection database
EcuadorOrellanaEstación Cientifica YasuníNogueira et al. 2019
EcuadorOrellanaLoretoUSNM 204125; VertNet
EcuadorOrellanaLoreto, 4 km NW ofUSNM 204125; VertNet
EcuadorOrellanaLos MonosNogueira et al. 2019
EcuadorOrellanaNPF RepsolNogueira et al. 2019
EcuadorOrellanaPozo Petrolero CapirónNogueira et al. 2019
EcuadorOrellanaPozo Petrolero NashiñoNogueira et al. 2019
EcuadorOrellanaPozo Petrolero Zine 1Nogueira et al. 2019
EcuadorOrellanaPozo YarentaroNogueira et al. 2019
EcuadorOrellanaPuerto MurialdoNogueira et al. 2019
EcuadorOrellanaReserva Río BigalGarcía et al. 2021
EcuadorOrellanaSan José de PayaminoMaynard et al. 2016
EcuadorOrellanaSanta TeresitaCarvajal-Campos 2020
EcuadorOrellanaTiputini Biodiversity StationCisneros-Heredia 2003
EcuadorOrellanaTukanariNogueira et al. 2019
EcuadorPastazaAndoasAMNH 49074; examined
EcuadorPastazaArmadillo BiNaturalist; photo examined
EcuadorPastazaChichirota, 1 km N ofNogueira et al. 2019
EcuadorPastazaConamboOrtega-Andrade 2010
EcuadorPastazaCopatazaNogueira et al. 2019
EcuadorPastazaFinca HeimatlosiNaturalist; photo examined
EcuadorPastazaKapawi LodgeiNaturalist; photo examined
EcuadorPastazaMontalvoNogueira et al. 2019
EcuadorPastazaParroquia 10 de AgostoCosta et al. 2013
EcuadorPastazaPavacachiCosta 2010
EcuadorPastazaPeter Archer’s placePhoto by Yatin Kalki
EcuadorPastazaPindoyacuOrtega-Andrade 2010
EcuadorPastazaPozo NantoNogueira et al. 2019
EcuadorPastazaPuyo, barrio los ÁngelesiNaturalist; photo examined
EcuadorPastazaPuyo, finca Pablo AriasNogueira et al. 2019
EcuadorPastazaPuyo, PicoliniNaturalist; photo examined
EcuadorPastazaPuyo, UEAiNaturalist; photo examined
EcuadorPastazaPuyupungo, 1 km N ofSMF 90964; GBIF
EcuadorPastazaRío CopatazaiNaturalist; photo examined
EcuadorPastazaRío CurarayNogueira et al. 2019
EcuadorPastazaRío LiguinoCosta et al. 2013
EcuadorPastazaRío MaritayacuNogueira et al. 2019
EcuadorPastazaRío Negro, 3 km SE ofNogueira et al. 2019
EcuadorPastazaRío OglánUCE 058; GBIF
EcuadorPastazaRío PuyoiNaturalist; photo examined
EcuadorPastazaRío TigreCosta et al. 2013
EcuadorPastazaSarayacuNogueira et al. 2019
EcuadorPastazaShellLehr et al. 2004
EcuadorPastazaSumak Kawsay In SituBentley et al. 2021
EcuadorPastazaTamboCosta et al. 2013
EcuadorPastazaTinajas del Río AnzuiNaturalist; photo examined
EcuadorPastazaValle HermosoCosta et al. 2013
EcuadorPastazaVillabo BNogueira et al. 2019
EcuadorSucumbíosComunidad Santa elenaNogueira et al. 2019
EcuadorSucumbíosLa Selva LodgeNogueira et al. 2019
EcuadorSucumbíosLaguna GrandeNogueira et al. 2019
EcuadorSucumbíosLimoncocha Biological ReserveLACM 75172; VertNet
EcuadorSucumbíosPañacochaMHNG 2399.014; collection database
EcuadorSucumbíosPuerto LibreDuellman 1978
EcuadorSucumbíosSábalo VillageNogueira et al. 2019
EcuadorSucumbíosSan Pablo de KantesiyaMHNG 2412.054; collection database
EcuadorSucumbíosSani LodgeReptiles of Ecuador book database
EcuadorSucumbíosSanta Cecilia Duellman 1978
EcuadorSucumbíosSanta Elena, 11 km S ofiNaturalist; photo examined
EcuadorSucumbíosShushufindiNogueira et al. 2019
EcuadorZamora ChinchipeBombuscaroDarwin Núñez, pers. comm.
EcuadorZamora ChinchipeCampo ECSALoaiza-Lange 2023
EcuadorZamora ChinchipeEl PadmiLoaiza-Lange 2023
EcuadorZamora ChinchipeEl TamboDarwin Núñez, pers. comm.
EcuadorZamora ChinchipePachicutzaiNaturalist; photo examined
EcuadorZamora ChinchipePodocarpusDarwin Núñez, pers. comm.
EcuadorZamora ChinchipeRío TundaymeLoaiza-Lange 2023
EcuadorZamora ChinchipeTundaymeiNaturalist; photo examined
EcuadorZamora ChinchipeValle del QuimiBetancourt et al. 2018
EcuadorZamora ChinchipeZamoraDarwin Núñez, pers. comm.
EcuadorZamora ChinchipeZurmiiNaturalist
PeruAmazonasAguaruna VillageMVZ 163273; VertNet
PeruAmazonasHuambisa VillageMVZ 175321; VertNet
PeruAmazonasHuampamiUSNM 316603; VertNet
PeruAmazonasImasitaMVZ 175322; VertNet
PeruAmazonasSan Antonio, Río CenepaUSNM 316601; VertNet
PeruLoretoAndoas Nogueira et al. 2019
PeruLoretoCampo AndoasValqui Schult 2015
PeruLoretoMishanaMPM 10435; VertNet
PeruLoretoMoroponMCZ 151771; VertNet
PeruLoretoReserva Nacional Pacaya SamiriaiNaturalist; photo examined
PeruSan MartínSan AntonioiNaturalist; photo examined