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Drymobius margaritiferus

January 01, 1970

Drymobius margaritiferus, commonly known as the speckled racer, is a species of nonvenomous colubrid snake native to the Americas. The specific name, margaritiferus, means "pearl-bearing" in Latin, referring to the pearl-like spots on the dorsal scales.

Drymobius margaritiferus
Drymobius margaritiferus, Tamaulipas, Mexico
Scientific classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Reptilia
Order: Squamata
Suborder: Serpentes
Family: Colubridae
Genus: Drymobius
Species:
D. margaritiferus
Binomial name
Drymobius margaritiferus
(Schlegel, 1837)
Synonyms

Geographic range and habitat edit

This species ranges throughout Central America from the Isthmus of Tehuantepec and Yucatán Peninsula, southward to Panama and adjacent areas of northwest Colombia, occurring at elevations from sea level up to 4,750 feet (1,453 m). Northward, it is found in the coastal lowlands and lower exterior slopes of the Sierra Madres of Mexico, up the west coast to Sonora, and up the east coast to northern Tamaulipas. The northern limit of its distribution ranges into extreme south Texas, USA, where it is uncommon to rare in a few of the southernmost counties of the state.[3][4][5]

Speckled racers occur in a wide variety of habitats, including: forest, forest edges and clearings, secondary growth, riparian zones, savannahs, marshlands, pastures, and roadsides.[3][6] It is often said to favor humid and wet areas with permanent water sources.[7][3][8] However, these snakes have been found in areas where no water was apparent, and habitats include tropical dry forests and tropical arid forests.[9][10][11] In Costa Rica, it is described as "ubiquitous in all but the most humid lowland and pre-montane zones," including dry lowland forests.[6]

Description edit

 
Drymobius margaritiferus

The speckled racer is typically black in color, with distinctive yellow and blue spotting, and one light-colored spot on each scale,[12] which gives the snake an overall greenish hue. The labials are yellow, with black sutures.[2] The underside is typically yellow to green. They average 30–40 in. (76–102 cm) in length, with a record specimen documented at 50 in. (127 cm).[7]

The dorsal scales, which are feebly keeled middorsally, but smooth on the flanks, are arranged in 17 rows. The ventrals number 142–168; the subcaudals, 85–126.[13]

Natural history edit

As the name "racer" implies, it is a fast and agile species that is predominantly diurnal.[8] It has been described as a nervous species, and will not hesitate to bite in self-defense when restrained or handled.[3][12] Death feigning behavior, or thanatosis, was reported for two out of seven (28.5%) specimens that were caught and handled during field surveys conducted in Tamaulipas, Mexico.[10]

They will consume a wide variety of prey, but primarily feed on frogs and toads.[7] One study of 36 Guatemalan and Mexican specimens with food items in their stomachs found 86% had anurans (predominantly Eleutherodactylus), 8% lizards, 4% reptile eggs, and 2% small mammals.[14] Juveniles are known to eat insects.[6]

They are oviparous, typically laying eggs in the spring, although in southern areas, the species is known to deposit eggs as early as February and March. Clutch sizes range from two to eight eggs that are usually 1.5 inches (3.8 cm) in length. Incubation is typically eight to nine weeks, with hatchlings measuring 6 to 10½ inches (15.2–27.6 cm) long.[3]

Subspecies edit

There are four recognized subspecies of D. margaritiferus:

Conservation status edit

The speckled racer is a threatened species in the state of Texas, USA, where it is uncommon to rare.[17] In some regions of Mexico and Central America, it is a common species.[3][6]

References edit

 
Wikimedia Commons has media related to Drymobius margaritiferus.
 
Wikispecies has information related to Drymobius margaritiferus.
  1. ^ Flores-Villela, O.; Hammerson, G.A.; Ines Hladki, A.; Köhler, G.; Lamar, W.; Ramírez Pinilla, M.; Renjifo, J.; Urbina, N. (2017). "Drymobius margaritiferus". IUCN Red List of Threatened Species. 2017: e.T197481A2488545. doi:10.2305/IUCN.UK.2017-2.RLTS.T197481A2488545.en. Retrieved 2 December 2022.
  2. ^ a b Boulenger, G.A. (1894). Catalogue of the Snakes in the British Museum (Natural History). Volume II., Containing the Conclusion of the Colubridæ Aglyphæ. London: Trustees of the British Museum (Natural History). (Taylor and Francis, Printers.) xi + 328 pp. + Plates I.- XX. (Drymobius margaritiferus, pp. 17-18.).
  3. ^ a b c d e f Werler, John E. and James R. Dixon. 2000. Texas Snakes: Identification, Distribution, and Natural History. University of Texas Press. Austin, Texas. xv, 417 pp. ISBN 0-292-79130-5
  4. ^ Köhler, Gunther. 2008. Reptiles of Central America, 2nd. ed. Herpeton Verlag. Offenbach, Germany. 460 pp. ISBN 3-936180-28-8
  5. ^ "Drymobius margaritiferus". Herps of Texas. University of Texas at Austin. Retrieved 2010-04-27.
  6. ^ a b c d Savage, J. M. 2002. The Amphibians and Reptiles of Costa Rica, A Herpetofauna between Two Continents, between Two Seas. University of Chicago Press, Chicago, Illinois. xx, 934 pp.
  7. ^ a b c Conant, Roger (1975). A Field Guide to Reptiles and Amphibians of Eastern and Central North America. Second Edition. Boston: Houghton Mifflin. 429 pp. ISBN 0-395-19977-8 (paperback). (Drymobius margaritiferus, p. 186 + Plate 32 + Map 142.)
  8. ^ a b Lee, J. C. 1996. The Amphibians and Reptiles of the Yucatán Peninsula. Comstock Publishing Associates, Cornell University Press, Ithaca, New York. xii, 500 pp. ISBN 0-8014-2450-X
  9. ^ a b c d e Wilson, Larry David, and John R. Meyer. 1985. The Snakes of Honduras, 2nd. ed. Milwaukee Public Museum. x, 150 pp. ISBN 0-89326-115-7
  10. ^ a b Farr, William L. and David Lazcano (2011). Natural History Notes: Drymobius margaritiferus, Thanatosis. Herpological Review, 42(4); 613.
  11. ^ McCranie, J. R. 2011. The Snakes of Honduras: Systematics, Distribution, and Conservation.. Contributions to Herpetology, Vol. 26. Society for the Study of Amphibians and Reptiles. x, 714 pp. ISBN 978-0-916984-81-6
  12. ^ a b Schmidt, K.P.; D.D. Davis (1941). Field Book of Snakes of the United States and Canada. New York: G.P. Putnam's Sons. 365 pp. (Drymobius margaritiferus, pp. 131-133, Figure 31.)
  13. ^ Smith, H.M.; E.D. Brodie, Jr. (1982). Reptiles of North America: A Guide to Field Identification. New York: Golden Press. 240 pp. ISBN 0-307-13666-3 (paperback). (Drymobius margaritiferus, pp. 188-189.)
  14. ^ Seib, R. L. (1984). Prey use in three syntopic neotropical racers. Journal of Herpetology. 18(4): 412-420.
  15. ^ a b c Liner, Ernest A. and Gustavo Cass-Andreu. (2008). Standard Spanish, English and Scientific Names of the Amphibians and Reptiles of Mexico (2nd. ed.). Herpetological Circular No. 38. Society for the Study of Amphibians and Reptiles. iv, 162 pp. ISBN 978-0-916984-75-5
  16. ^ The Reptile Database. www.reptile-database.org.
  17. ^ "Endangered Species". Texas Parks and Wildlife Department. Retrieved 2012-10-16.

Further reading edit

  • Schlegel, H. (1837). Essai sur la physionomie des serpens. Amsterdam: M.H. Schonekat. Partie Générale. xxviii + 251 pp. (Herpetodryas margaritiferus, p. 151.) AND Partie Descriptive. 606 + xvi pp. (Herpetodryas margaritiferus, pp. 184–185.)

External links edit

  • Species Drymobius margaritiferus at The Reptile Database


January 01, 1970
drymobius, margaritiferus, commonly, known, speckled, racer, species, nonvenomous, colubrid, snake, native, americas, specific, name, margaritiferus, means, pearl, bearing, latin, referring, pearl, like, spots, dorsal, scales, tamaulipas, mexico, conservation,. Drymobius margaritiferus commonly known as the speckled racer is a species of nonvenomous colubrid snake native to the Americas The specific name margaritiferus means pearl bearing in Latin referring to the pearl like spots on the dorsal scales Drymobius margaritiferus Drymobius margaritiferus Tamaulipas Mexico Conservation status Least Concern IUCN 3 1 1 Scientific classification Domain Eukaryota Kingdom Animalia Phylum Chordata Class Reptilia Order Squamata Suborder Serpentes Family Colubridae Genus Drymobius Species D margaritiferus Binomial name Drymobius margaritiferus Schlegel 1837 Synonyms Herpetodryas margaritiferus Schlegel 1837 Leptophis margaritiferus A M C Dumeril Bibron amp A H A Dumeril 1854 Dromicus margaritiferus Gunther 1858 Thamnosophis margaritiferus Jan 1863 Drymobius margaritiferus Boulenger 1894 2 Contents 1 Geographic range and habitat 2 Description 3 Natural history 4 Subspecies 5 Conservation status 6 References 7 Further reading 8 External linksGeographic range and habitat editThis species ranges throughout Central America from the Isthmus of Tehuantepec and Yucatan Peninsula southward to Panama and adjacent areas of northwest Colombia occurring at elevations from sea level up to 4 750 feet 1 453 m Northward it is found in the coastal lowlands and lower exterior slopes of the Sierra Madres of Mexico up the west coast to Sonora and up the east coast to northern Tamaulipas The northern limit of its distribution ranges into extreme south Texas USA where it is uncommon to rare in a few of the southernmost counties of the state 3 4 5 Speckled racers occur in a wide variety of habitats including forest forest edges and clearings secondary growth riparian zones savannahs marshlands pastures and roadsides 3 6 It is often said to favor humid and wet areas with permanent water sources 7 3 8 However these snakes have been found in areas where no water was apparent and habitats include tropical dry forests and tropical arid forests 9 10 11 In Costa Rica it is described as ubiquitous in all but the most humid lowland and pre montane zones including dry lowland forests 6 Description edit nbsp Drymobius margaritiferus The speckled racer is typically black in color with distinctive yellow and blue spotting and one light colored spot on each scale 12 which gives the snake an overall greenish hue The labials are yellow with black sutures 2 The underside is typically yellow to green They average 30 40 in 76 102 cm in length with a record specimen documented at 50 in 127 cm 7 The dorsal scales which are feebly keeled middorsally but smooth on the flanks are arranged in 17 rows The ventrals number 142 168 the subcaudals 85 126 13 Natural history editAs the name racer implies it is a fast and agile species that is predominantly diurnal 8 It has been described as a nervous species and will not hesitate to bite in self defense when restrained or handled 3 12 Death feigning behavior or thanatosis was reported for two out of seven 28 5 specimens that were caught and handled during field surveys conducted in Tamaulipas Mexico 10 They will consume a wide variety of prey but primarily feed on frogs and toads 7 One study of 36 Guatemalan and Mexican specimens with food items in their stomachs found 86 had anurans predominantly Eleutherodactylus 8 lizards 4 reptile eggs and 2 small mammals 14 Juveniles are known to eat insects 6 They are oviparous typically laying eggs in the spring although in southern areas the species is known to deposit eggs as early as February and March Clutch sizes range from two to eight eggs that are usually 1 5 inches 3 8 cm in length Incubation is typically eight to nine weeks with hatchlings measuring 6 to 10 inches 15 2 27 6 cm long 3 Subspecies editThere are four recognized subspecies of D margaritiferus Drymobius m margaritiferus Schlegel 1837 Northern speckled racer 15 Atlantic versant Texas to Colombia and sections of Pacific in Chiapas Mexico and southern range 9 Drymobius m fistulosus H M Smith 1942 Central American speckled racer 15 Pacific versant from southern Sonora to the Isthmus of Tehuantepec 9 Drymobius m occidentalis Bocourt 1890 Western speckled racer 15 Pacific versant from eastern Chiapas Mexico to El Salvador 9 Drymobius m maydis Villa 1968 16 Corn Islands Nicaragua 9 Conservation status editThe speckled racer is a threatened species in the state of Texas USA where it is uncommon to rare 17 In some regions of Mexico and Central America it is a common species 3 6 References edit nbsp Wikimedia Commons has media related to Drymobius margaritiferus nbsp Wikispecies has information related to Drymobius margaritiferus Flores Villela O Hammerson G A Ines Hladki A Kohler G Lamar W Ramirez Pinilla M Renjifo J Urbina N 2017 Drymobius margaritiferus IUCN Red List of Threatened Species 2017 e T197481A2488545 doi 10 2305 IUCN UK 2017 2 RLTS T197481A2488545 en Retrieved 2 December 2022 a b Boulenger G A 1894 Catalogue of the Snakes in the British Museum Natural History Volume II Containing the Conclusion of the Colubridae Aglyphae London Trustees of the British Museum Natural History Taylor and Francis Printers xi 328 pp Plates I XX Drymobius margaritiferus pp 17 18 a b c d e f Werler John E and James R Dixon 2000 Texas Snakes Identification Distribution and Natural History University of Texas Press Austin Texas xv 417 pp ISBN 0 292 79130 5 Kohler Gunther 2008 Reptiles of Central America 2nd ed Herpeton Verlag Offenbach Germany 460 pp ISBN 3 936180 28 8 Drymobius margaritiferus Herps of Texas University of Texas at Austin Retrieved 2010 04 27 a b c d Savage J M 2002 The Amphibians and Reptiles of Costa Rica A Herpetofauna between Two Continents between Two Seas University of Chicago Press Chicago Illinois xx 934 pp a b c Conant Roger 1975 A Field Guide to Reptiles and Amphibians of Eastern and Central North America Second Edition Boston Houghton Mifflin 429 pp ISBN 0 395 19977 8 paperback Drymobius margaritiferus p 186 Plate 32 Map 142 a b Lee J C 1996 The Amphibians and Reptiles of the Yucatan Peninsula Comstock Publishing Associates Cornell University Press Ithaca New York xii 500 pp ISBN 0 8014 2450 X a b c d e Wilson Larry David and John R Meyer 1985 The Snakes of Honduras 2nd ed Milwaukee Public Museum x 150 pp ISBN 0 89326 115 7 a b Farr William L and David Lazcano 2011 Natural History Notes Drymobius margaritiferus Thanatosis Herpological Review 42 4 613 McCranie J R 2011 The Snakes of Honduras Systematics Distribution and Conservation Contributions to Herpetology Vol 26 Society for the Study of Amphibians and Reptiles x 714 pp ISBN 978 0 916984 81 6 a b Schmidt K P D D Davis 1941 Field Book of Snakes of the United States and Canada New York G P Putnam s Sons 365 pp Drymobius margaritiferus pp 131 133 Figure 31 Smith H M E D Brodie Jr 1982 Reptiles of North America A Guide to Field Identification New York Golden Press 240 pp ISBN 0 307 13666 3 paperback Drymobius margaritiferus pp 188 189 Seib R L 1984 Prey use in three syntopic neotropical racers Journal of Herpetology 18 4 412 420 a b c Liner Ernest A and Gustavo Cass Andreu 2008 Standard Spanish English and Scientific Names of the Amphibians and Reptiles of Mexico 2nd ed Herpetological Circular No 38 Society for the Study of Amphibians and Reptiles iv 162 pp ISBN 978 0 916984 75 5 The Reptile Database www reptile database org Endangered Species Texas Parks and Wildlife Department Retrieved 2012 10 16 Further reading editSchlegel H 1837 Essai sur la physionomie des serpens Amsterdam M H Schonekat Partie Generale xxviii 251 pp Herpetodryas margaritiferus p 151 AND Partie Descriptive 606 xvi pp Herpetodryas margaritiferus pp 184 185 External links editSpecies Drymobius margaritiferus at The Reptile Database Retrieved from https en wikipedia org w index php title Drymobius margaritiferus amp oldid 1215252454, wikipedia, wiki, book, books, library,

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