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IDENTIFYING SNAKES

IDENTIFYING SNAKES. Morphology, keys and DNA diagnostics. MORPHOLOGY: Head shape. http://www.virginiaherpetologicalsociety.com/identification-keys/id-keys-snakes/virginia_snake_identification.htm. MORPHOLOGY: Head shape. Colubrid -Elapid type. Viperid type. VENOMOUS or NON-VENOMOUS?

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IDENTIFYING SNAKES

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  1. IDENTIFYING SNAKES Morphology, keys and DNA diagnostics

  2. MORPHOLOGY: Head shape http://www.virginiaherpetologicalsociety.com/identification-keys/id-keys-snakes/virginia_snake_identification.htm

  3. MORPHOLOGY: Head shape Colubrid-Elapid type Viperid type

  4. VENOMOUS or NON-VENOMOUS? Front-fanged or non-front fanged: all snakes are potentially venomous As are some lizards…… www.venomdoc.com

  5. MORPHOLOGY: Body Pattern UNIFORM SPECKLED STRIPED SPOTTED BLOTCHED DIAMONDS BANDED RINGED http://www.flmnh.ufl.edu/herpetology/fl-guide/snakekey.htm

  6. MORPHOLOGY: Head Pattern

  7. MORPHOLOGY: Scale counts 1. Number of dorsal scales at mid-body

  8. MORPHOLOGY: SCALE STRUCTURE SMOOTH KEELED http://www.flmnh.ufl.edu/herpetology/fl-guide/snakekey.htm

  9. MORPHOLOGY: Scale counts 2. Number of ventral, anal and subcaudal scales

  10. MORPHOLOGY: Head scales Snakes of Western and Central Africa http://people.whitman.edu/~clarkedn/characterglossary.html

  11. Scale row reductions Ovophis spp.

  12. KEYS How to Use this Key: Start with the first question. Decide whether 1a or 1b best describes the characteristics of the snake you are trying to identify. (There are links to examples of these traits if you need help.) If the snake is striped, click on 6; if it is not striped, click on 2. Your choice will lead you to the next appropriate pair of questions. Work through the questions, each time choosing the characteristic that best matches your snake from the two choices. This will lead you to the final choice which identifies the snake. http://www.flmnh.ufl.edu/herpetology/fl-guide/snakekey.htm 1. Traditional dichotomous keys

  13. Quinn Snake Identification Chart 2. Flowchart

  14. 3. Interactive On-line

  15. 3. Interactive On-line

  16. 3. Interactive On-line http://www.discoverlife.org/20/q?guide=Snakes

  17. http://www.herpsofnc.org/herps_of_nc/snakes/SnakeID/search.asphttp://www.herpsofnc.org/herps_of_nc/snakes/SnakeID/search.asp 3. Interactive On-line

  18. Species File Software http://orthoptera.speciesfile.org/Common/key/KeyDriver.aspx?KeyBlockID=10002 3. Interactive On-line

  19. (DEscriptionLanguage for TAxonomy) http://delta-intkey.com/lep/index.htm 3. Interactive On-line

  20. PROBLEMS TO BE SOLVED A key is only as good as the data that it is based on Most venomous snakes have not yet been sampled within India well Outstanding issues needing further work in many spp. Najaspp (N. najaand N. kaouthia) Echisspp (E. carinatus and E. sochureki) Daboiarusselii Pitvipers (many spp)

  21. http://pages.bangor.ac.uk/~bss166/Taxa/AsNaja.htm Asian cobras Naja (11 spp. since 2000) oxiana mandalayensis atra kaouthia naja phillipinensis siamensis samarensis sumatrana sagittifera sputatrix

  22. Cryptic diversity of cobras in India? Mitochondrial DNA Morphology N. kaouthia N. kaouthia N. kaouthia N. kaouthia N. kaouthia N. sagittifera N. sagittifera N. kaouthia N. oxiana N. oxiana N. najaSri Lanka N. najaSri Lanka N. najaNepal N. najaNepal Najanaja Najakaouthia Najaoxiana N. najaPakistan 0.01 • Cryptic species associated with N. kaouthia? • Deep divergences in N. naja Wüster & Thorpe 1992

  23. Morphology vs. molecules in Najanaja and the importance of sampling Morphological cline vs. deep molecular splits: one species or two? Morphology ? N. najaNepal N. najaNepal N. najaPakistan N. najaSri Lanka N. najaSri Lanka

  24. Bungarusniger Cryptelytropserythrurus Ovophismonticola Najaspp. Echissochureki/ E. carinatus ? Cryptelytrops spp. Najasagittifera Peltopleormacrolepis Trimeresurusmalabaricus Hypnalehypnale Mohapatraet al. (2011) PLoSNegl Trop Dis 5(4): e1018. doi:10.1371/journal.pntd.0001018

  25. DNA IDENTIFICATION: THE WAY FORWARD? Pookand McEwing(2005)Toxicon 46: 711-715 - mtDNAPCR amplified from dried venom samples - 100-200 mg dried venom used Kuch (unpublished): bite site swabs successfully used to identify biting species in Bangladesh Relies on presence of species sequences in “barcoding” databases against which query sequence is matched More useful for research than diagnostics

  26. DNA IDENTIFICATION: THE WAY FORWARD? With enough information, specific diagnostic tests can be designed to identify important species by length differences in amplified product alone (time c. 30 mins, cost c. $10-20)

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