Everything has its shadowy side. — Tennessee Williams, The Night of the Iguana
lso known as the black spiny-tailed iguana or just spiny tailed iguana, this is a large terrestrial species of iguana that is found in Mexico and Central America. Notably, it has been introduced to Florida, which has more than its share of exotic species. It is the largest species of the genus Ctenosaura – adult males can grow to just over 4 ft long, females are a bit smaller. Ctenosaura from the Greek ctenos (comb – referring to the spines on the back) andsaura (lizard). The species name similis means “similar to” – which apparently is common in taxonomy when describing a new animal. So this loosely translates to similar to a lizard with a comb on its back.
This lizard is variable in color but generally the adults have a whitish gray to tan color with 4-12 dark bands on their back that extend along the sides. During the breeding season the males develop an orange-rust color around the head and throat with highlights of blue and pink on their jowls. Adult males and females are dimorphic – they look a bit different. Males have a well-developed dorsal crest and a small dewlap – a crescent of skin that can be extended under the throat. It is not inflated in this species but a small bone bows out to extend the dewlap during times of threat, courtship, or while defending territory.
These iguanas are highly gregarious and territorial, live in colonies, and are ruled by a strict pecking order of dominance. One male in the colony is dominant while others may also hold some territory that they defend against one another, except the leader. Mating occurs in the spring and males will show their dominance, like many other lizards, by head bobbing, inflating their body, and doing “push-ups”. Head bobbing:https://www.youtube.com/watch?v=-jUoaJgQ4KY
Males will chase down a female and subdue her for mating. Females will dig a nest in eight to ten weeks and lay up to 30 eggs and defend the nest. The hatchlings will dig their way to the surface after incubating for about 90 days. These juveniles are green with brown markings. Sexually maturity is attained at 3-4 years of age. If they manage to get past the vulnerable early years of life black iguanas can live more than 60 years. Black iguanas are mainly herbivorous and forage on flowers, leaves, stems, and fruit, but they will eat smaller animals, eggs, and insects. They have been known to eat rodents, bats, frogs, and small birds. Juveniles eat more insects – which is typical of many lizard and bird species as the rapidly growing youngsters need more protein.
The species has been described as “belligerent” and will bite or wound an aggressor with its tail. While they can climb trees they tend to be much more terrestrial than arboreal and often seek refuge in the rocky areas with many crevices. They are among the fastest running lizards – clocked at 21.7 mph, and can go bipedal – running on their hind legs.
They are hunted by man as a food source and are at times considered a potent medicine – imparting some of its strength to the person who consumes it. And it also is supposed to be a cure for impotence – which seems to be the case for almost any odd wild animal part. I’ve come across these critters in several places including in the Yucatan. Once I was hanging out on a beach on the island of Cozumel with my then partner, which after a while gets a little boring, so I decided to go see what reptiles were around at the edge of the forest. Sure enough, there was a 3.5 foot-long male iguana hanging out in the sun along the forest edge. I was munching on a soft taco so decided to see if I could bait him towards me with some tortilla.
He obliged coming towards me as I tossed the bait closer. I squatted down to make myself less intimidating but at some defined distance, about 3 feet or so, he became rather suspicious of my ploy. I tossed a piece of tortilla closer. He nudged closer, tilted his head so he could keep an eye on me, and then slowly bent his head towards the ground and scooped up the morsel with his broad tongue. He then just stopped to watch me. He knew the game, but liked the tortilla. I knew that he knew what was up – and so, game on. I tossed the next tortilla at that critical distance – just beyond his comfort level and maybe, just within my pounce distance. He went for it and I jumped.
I pinned him to the ground just behind his front legs as he opened his mouth and hissed loudly! So I picked him up by the back, above his front and hind legs. It was then that I realized that my camera was about 100 yards across the beach and it would have been quite the spectacle, even for me, to march across the sand carrying a large lizard. About this time a small crowd of youngsters started admiring my catch and were peppering me with questions in Spanish – Is that your pet? What are you doing? Are you taking him home? Are you going to eat him?
Trying to explain that no, I’m an ecologist with an obsession with catching lizards was beyond my Spanish so I settled for “Queria coger el dragon” (I wanted to catch the dragon) – which seemed to satisfy and amuse them. No one else wanted to hold him so I slowly put him down on the ground, half expecting him to try to bite. But instead, he just sat there on the ground motionless for at least a minute. We silently looked at one another – all with raised eyebrows, until one brave soul motioned towards his tail and I nodded in agreement. He bent down and tapped the end of the iguana’s tail and that was it – our lizard scooted into the forest as if shot from a cannon, so startling us all that we let out a squeal of delight in unison.