We are currently working with a small group of Cachryx defensor. These were originally described by Cope as Cachryx
defensor, and then later grouped with Ctenosaura Boulenger and Gunther. In 2017 Malone found justification--with MtDNA--to remove both defensor and alfredschmidti from the genus Ctenosaura and resurrect the genus Cachryx. One of the most interesting discoveries of this paper is that the genus Cachryx was most closely related to Conolophus (Galapagos Land Iguanas), and only distantly related to Ctenosaura.
I have a small group of true Captive Bred Yucatán Spiny Tailed Iguanas. We acquired the entire group from our friend Josh Marki of Marki Reptiles.
I had originally imported the core of the group as babies for him, from Juergen Schmidt. In addition to this bloodline, there is also one female from Maria Heuter's breeding which should be large enough to breed at some point soon.
I want to note that reptile/amphibian and bird smuggling out of Mexico has become a serious problem. The proliferation of poached wildlife from Mexico is largely due to the accessibility of customers that social media has provided traffickers. Paired with the long-standing tradition of herpetoculture turning a blind eye to our worst actors. A few well-known online retailers have willfully laundered out wild-caught defensor in large numbers in recent years. The vast majority of which didn't have a chance at survival. Ethical and legal importation of foundation stock specimens can have its issues... but when this is done by the lowest common denominator too often the animals pay the price. I would strongly advocate any would-be customer to press for proof that the animals they are buying are legitimately captive-bred regardless of the price.