I run a wildlife rehabilitation center and also take in unwanted exotics. I have received many iguanas over the years (I have five now ranging from 14 inches snout-to-vent length to one more than 2 ½ feet SVL). However, I just received one that has me stumped.

It is a male, approximately 20 inches SVL. He is in good health and shape. He has two spikes (a half inch and a quarter inch long) on the top of his nose, one behind the other. The spikes are same as on his back, only smaller.

I have never seen an iguana with spikes between the nostrils. Is this a different kind of iguana, or just a natural occurrence that I have missed?

I assume that you are talking about the common green iguana (Iguana iguana) and not the rhinoceros iguana (Cyclura cornuta cornuta), which does have some interesting head ornamentation, from whence it received its name.

I have seen some green iguanas with raised scales on the head, on the midline, between the nostrils, which resemble the horns of a rhinoceros. My thoughts on the subject are that this is just an aberrant form of the regular green iguana, and that it is not a separate subspecies. It appears to be just a cool anomaly. If anyone knows differently, then it’s not anything that I have seen published, and I would welcome any information that anyone has on them.

Perhaps you could send us a digital photo for us to put in my column? Am I to understand that the dorsal spines are not like regular green iguana spines?

Both my husband and I have seen these green iguanas with hornlike projections on the head, and we believe them to be a normal variation, almost always found in males.