LIMBS 



The number of fingers and toes sometimes aids in identification. Klec 

 turns, for example, has four toes while the axylotl, which sometimes much re 

 sembles it, has five. The thickened pads on hand and foot, palmar and plantar 

 tubercles, vary in different species. Some of the specialized forms show vary 

 ing degrees of webbing of the toes. 



TAIL 



In general, the more aquatic species have flattened or finned tails, the 

 more terrestrial ones have more cylindrical tails. The terrestrial species some' 

 times show a constriction area at the base of the tail, which usually indicates 

 the ability of the animal to snap off^ its tail when threatened, the twitching 

 tail often serving as a decoy while its owner slips quietly away. A tail so 

 lost is gradually replaced, but the second is seldom as well developed. 



COLOR 



There is much variation in color pattern, both between individuals and 

 in the same individual during its growth. Spotted or plain colored adults may 

 have striped or barred larvae. Young mudpuppies {J^ecturus maculosus) 

 show lengthwise stripes, young of the black Jefferson and narrow-mouthed 

 salamanders, Amhystoma jejfersomanum and Amhystoma texanum, have a dis- 

 tinct pattern of cross bars. The young of Eurycea may go through a bewilder- 

 ing series of spotted or striped markings before assuming adult coloration. The 

 adults of some species show great variation. Amhystoma tigrinum, the tiger 

 salamander, varies from mostly black to mostly yellow. The common newt, 

 Triturus viridescens vindescens, has a greenish water stage and a red land stage. 

 In preserved specimens red color usually disappears completely and yellows and 

 blacks fade considerably. The key is based on average adult specimens. 



OUTLINE OF CLASSIFICATION OF NATIVE SALAMANDERS 



Order CAUDATA (or Urodela) of Class AMPHIBIA 



Tail retained throughout life; pectoral and pelvic girdles unspecialized 

 Suborder PROTEIDA 

 Family NECTURIDAE 



With external gills throughout life; no maxillary; short series of 

 teeth on premaxillary; complete row of teeth on vomero-palatine 

 and pterygoid; with four digits on each limb 

 One genus — J^ecturus (7 species) Mudpuppies 

 Suborder MUTABILIA 

 Family AMPHIUMIDAE 



One pharyngeal gill slit on each side; limbs present but much 



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