Back in September, we saw an Anolis carolinensis with a bizarre skeletal anomaly, the zig-zag tail. Several readers commented that this was quite a common trait, especially among captive lizards. I wanted to continue this theme with a curious Anolis cybotes specimen I found while CT scanning.
This image of a volume rendering of the skeleton shows a typical A. cybotes male pelvis, where the ilia articulates with the sacral vertebrae (denoted by arrow).
Now, the image below shows R186747, a male A. cybotes collected by Luke Mahler in the Dominican Republic. The lateral process of the first tail vertebrae has been adopted to form the sacrum on the left side, while the right remains standard, and the right side of the pubis appears to have an old healed fracture.
When I discussed this with my colleague, Kevin Mulder, he immediately brought up the following x-ray images of A. smaragdinus and A. sagrei (left to right) specimens (and he has several others) that also have asymmetrical sacral vertebrae and deformed transverse processes on the tail vertebrae. Therefore it appears this condition may be more common…
My gut feeling for the A. cybotes specimen was that this is more likely due to post-hatching trauma (such as escaped predation incident), rather than a developmental abnormality, but now I am not so sure. Do any readers have any ideas?
Regardless, it appears not to be a problematic condition since all of these animals were seemingly growing and living happily prior to being noosed!