Re: How can I distinguish between the plethodont amphibian genera?

Yael-
  First, see if the specimen has gills. If it doesn't have gills, check 
for a light line running from the eye to the mouth. If it's got that line, 
it's a _Desmognathus._ If it doesn't, look at the eyes and neck. If the 
neck is wider than the head and the eyes are not protruberant, then that 
also means it's a _Desmognathus._ But if the neck is narrower than the 
head (or at least no wider) and the eyes are protruberant, it's something 
else. Count the toes. If there are only four toes, you've got a 
_Batrachoseps._ If there are 5 toes, open its mouth to have a look at its 
tongue. If the tongue is attached in the front 
of its mouth, its either _Aneides_ or _Plethodon._ If the digits are 
square-tipped, or if the teeth protrude below the upper lip, it's 
_Aneides._ In _Plethodon,_ the digits are round-tipped and the teeth don't 
protrude.
  If the tongue attaches in the middle of the floor of the mouth, it's 
either _Eurycea_ or _Pseudotriton._ Of the two, only _Eurycea_ is found 
west of the Mississippi. If the specimen was collected east of the 
Mississippi, count the costal grooves on the animal's sides. If there are 
15 or fewer costal grooves and if the sides are darker than the back, then 
it's _Eurycea._ If there are 16 or more costal grooves, then it's 
_Pseudotriton._
  If the specimen DOES have gills, you'll need to count the gill slits -- 
vertical openings at the base of the gills in each side of the neck. 
_Desmognathus_ has four gill slits. If it has 3 gill slits, it's one of 
the other genera -- count the toes and proceed normally from there. Good 
luck!    
                                     Russell J. Hawley