Dichotomous Key/Selachimorpha

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Dichotomous Key: Selachimorpha
Kingdom: Animalia Phylum: Chordata Subphylum: Vertebrata Class: Chondrichthyes Subclass: Elasmobranchii Superorder: Selachimorpha

[edit] 1

• Anal fin
  • Present - #2
  • Not present - #3

[edit] 2

• Dorsal fins
  • One - Hexanchiformes
  • Two - #5

[edit] 3

• Body shape
  • Flattened - Squatiniformes
  • Fusiform - #4

[edit] 4

• Snout length
  • Long - Squaliformes
  • Short - Pristiophoriformes

[edit] 5

• Fin spines
  • Present - Heterodontiformes
  • Not present - #6

[edit] 6

• Mouth position
  • In front of eyes - Orectolobiformes
  • Behind eyes - #7

[edit] 7

• Nictitating membrane
  • Present - Carcharhiniformes
  • Not present - Lamniformes