Giant salamanders have evil teeth
August 14, 2019
Last September I spent a day in the LACM Herpetology collections with Jessie Atterholt, looking at weird features in crocs, lizards, snakes, and salamanders. I’ll have more to say about the specific things we were looking for in a month or so, after Jessie’s given her talk at SVPCA. This was just an incidental hit. We were looking at cryptobranchid (literally “hidden gill”) salamanders, because they’re big enough that you don’t need a microscope to see all their weird features. Cryptobranchids include the North American hellbender, Cryptobranchus alleganiensis, and the giant salamanders of China and Japan, Andrias davidianus and Andrias japonicus, respectively, plus a raft of fossil taxa.
This is the mandible of LACM 162475, a specimen of Andrias davidianus, in right lateral view. I’d never spent quality time with the skeleton of a giant salamander, and I was impressed with how evil their teeth are. Just in terms of general outline, these little murder-sticks wouldn’t look out of place in the jaw of a dromaeosaur. Click to enfangenate.
Jessie did an Instagram post on the upper jaw of Cryptobranchus a few months ago, and as long as you’re over there, have a look at the half a pig head that she just plastinated for our colleagues in WesternU’s College of Veterinary Medicine. It’s not the same pig as the one we hemisected last December, but I think it got cut at the same time.
Sauropod Vertebra Picture of the Week 
August 14, 2019 at 7:27 pm
Looks somewhat more malicious than a frog’s, but weren’t dromeosaurs’ intended for slicing? The amphibian food plan seems, generally, to get it down the throat whole. I’m vaguely surprised you don’t hear more cases of things digging their way back out.
August 14, 2019 at 8:41 pm
In my experience, herp “targeting” is not always precise and is sometimes wildly optimistic. I think there are quite a few cases of herps swallowing things they’d later regret. I know Darren has covered a few on TetZoo, but it has to be just the tip of a very big iceberg.
As for why gulp-and-swallow salamanders need such evil teeth, that’s a question for someone more knowledgeable than me. Maybe they have to chomp more often than we think?
August 15, 2019 at 9:21 am
How do the teeth look in anterior view? Are they narrow, blade-like slicers like those of dromaeosaurs? or are they broad, conical graspers?
August 15, 2019 at 11:59 pm
Sadly my photos do not say, I don’t know myself, and I lack the time right now to find out. But I’ll be grateful to anyone who does know.
August 16, 2019 at 1:15 am
A paper online “Anatomy of Cryptobranchus alleghaniensis” describes the teeth as conical.
August 16, 2019 at 10:49 am
Mystery solved, then: they’re not cutters, they’re holders to help the salamander draw the prey into its mouth.
August 17, 2019 at 2:54 pm
Still doesn’t make them any less scary…
(brrr…)