Ok! Lets do this again! I want answers! How do you tell T. granulosa from T. torosa?

[sde]

Hi all.

Ok, so I know that this has apparently come up in the past, but I could not find the thread, so I am trying to do a new one! So people, young and old, big and small, shy and outgoing, HOW DO YOU TELL THEM APART? It is a question that seems to leave me in curiosity, and I seem to never find a good answer.

I have hear that you can tell from the eyes. If they protrude the head, than its a T. torosa. But my newts have their eyes protruding, and they are NOT T. torosa. I have also heard that that is not a sure way, ( as it would seem from my newts ). I have heard that color size and certain physical characteristics ( i.e. tail longer ) can identify or at least help in identifying. But it personally think that all those can easily be ruled out. I also have heard of their tooth pattern, that T. granulosa have V shaped pattern, but you would be cruel to look on a live individual, so that can only be used on dead individuals. Obviously range is a good indicator, but what about where the ranges overlap? T. torosa are supposed to be more terrestrial, but you may not know how terrestrial the newts in your aria are, you cant monitor them all the time ( well you can with a radio tag, but not many people have those ).

So in the end I still have no idea how you can tell them apart without harming them or having a dead specimen.

So is there a way to tell, say on a field trip or something where you just want to know what species it is? A way that doesn't require tooth position determination, DNA samples etc..

So, what do you think?

-Seth

 

[mitchelljs]

Perhaps the best lay source I know is California Herps

 

[otolith]

The identification key mitchelljs just posted is the easiest and most comprehensive I've found. That website in general is great for most west coast herps. I live in an area of CA where three Taricha species (no T. sierrae) overlap. There are a few places I go herping where all three can be found, sometimes together under the same log. Dorsal and ventral coloration can be similar with granulosa and torosa but in areas where both live the T. granulosa will be darker dorsally (but not always). The light eye bands and eye position are the easiest giveaways (and what I use most often to differentiate them). The key on calherps has great photos of this.

Generally Taricha in CA are only seen during the breeding season. As soon as it gets hot in late spring they hunker down and aestivate. Terrestrial vs. aquatic is a poor ID indicator since all species are terrestrial outside of breeding. Even during the breeding season only males will be fully aquatic; females will retain their rough skin and go to water for breeding and egg laying only and leave the water immediately afterwards.

Differentiating between the two is sometimes very easy when you run into a population with all the "classic" characteristics. When in doubt look at the head.

Here are a few pictures of some T. torosa we found yesterday. First one is a female, the ones in the puddle are males.