Here is the slightly edited text of a post I recently made on this topic elsewhere:
The veiled chameleon (Chamaeleo calyptratus) was originally described in 1851 by Duméril & Bibron in a chapter titled “Caméléonines ou Chélopodes” of Duméril & Duméril’s edited volume “Catalogue méthodique de la collection des reptiles du Muséum d’Histoire Naturelle de Paris”. In 1869, Peters described a new species, Chamaeleo calcaratus in an article in the journal “Monatsberichte der Koniglich Preussischen Akademie der Wissenschaften zu Berlin”. Peters corrected the name in 1870 to Chamaeleo calcarifer in the same journal. In 1959, Chamaeleo calcarifer was reclassified as a subspecies of Chamaeleo chamaeleon by Hillenius. It wasn’t until 1984 that this taxon was reclassified as a subspecies of Chamaeleo calyptratus by Hillenius & Gasperetti in their Fauna of Saudi Arabia, resulting in the two subspecies that are recognized today: Chamaeleo calyptratus calyptratus and Chamaeleo calyptratus calcarifer.
Aside from introduced populations in the US, the nominate subspecies, Chamaeleo calyptratus calyptratus, occurs only in western/southwestern Yemen (Schmidt, 2001; Necas, 2004; Tilbury, 2010; Glaw, 2015). Here, they live in the rain belt of the country, along the western slopes of the mountains of the western highlands, between 500 and 2850m asl (Schmidt, 2001; Tilbury, 2010). Included in this distribution is a broad, high elevation valley where the species is common (Necas, 2004), but the species does not occur in the low-lying coastal plains (Tilbury, 2010). This area experience heavy rainfall as coastal clouds are pushed up in elevation by the wind. In fact, this area can receive as much as 2,000mm of rainfall a year (Schmidt, 2001; Necas, 2004). By contrast, Miami receives on average 1,570mm of rainfall a year. The vegetation in this part of Yemen is lush and even during the driest month, there is around 50mm of rainfall. Now, they do also live in the central high plains, which is much drier, but in this area they are mainly restricted to wadis, where water is available year round and there is sufficient moisture to allow vegetation to grow (Schmidt, 2001).
The subspecies, Chamaeleo calyptratus calcarifer, on the other hand, has only been found in southwest Saudi Arabia (Schmidt, 2001; Necas, 2004; Tilbury, 2010; Glaw, 2015). Here, they are found on the western foothill slopes of the Asir mountains up to about 1200m asl, down into the Tihama coastal plain (Tilbury, 2010).
The taxonomic validity of the subspecies Chamaeleo calyptratus calcarifer has been the subject of debate for years. Hillenius (1966) hypothesized that the type specimen may be a hybrid between Chamaeleo calyptratus and Chamaeleo arabicus. It was then shown via captive breeding in Germany that these two species can in fact interbreed, and that the resulting offspring closely resemble that of what is described as Chamaeleo calyptratus calcarifer (Schmidt, 2001; Necas, 2004; Tilbury, 2010). This has caused some authors to suggest that these animals may not represent a valid subspecies (e.g., Klaver & Böhme, 1997; Schmidt, 2001; Necas, 2004). Pending DNA analysis of the type specimen and specimens from wild populations, however, the taxon is still considered a valid subspecies (Tilbury, 2010; Glaw, 2015).
Morphologically, the subspecies Chamaeleo calyptratus calcarifer differs from the nominate subspecies by a lower casque, with males lacking the marked sexual dimorphism in casque size exhibited by the nominate form. Further, the males of this subspecies tend to not be as colorful as males of the nominate form (Tilbury, 2010). Previously, some captive specimens had been pictured in herpetoculture literature claiming to represent specimens of the subspecies Chamaeleo calyptratus calcarifer. Notably, Bartlett & Bartlett (1995) and Bartlett & Bartlett (2001) published two different photographs of the same brown chameleon reported to be Chamaeleo calyptratus calcarifer. Unfortunately, examination of these photographs reveal that they actually are of a young Chamaeleo calyptratus calyptratus with MBD, as evident by the bowed legs showing clear fractures. Annis (in de Vosjoli & Ferguson, 1995), on the other hand, published a black and white photograph from the aforementioned Hillenius & Gasperetti (1984) of a true example of Chamaeleo calyptratus calyptratus photographed in the field. More recently, color photographs of this subspecies in the wild are published in Tilbury (2010). Images found in these latter two sources clearly show that those previously published in other sources of captive specimens were not true Chamaeleo calyptratus calcarifer.
In fact, all the examples of Chamaeleo calyptratus in captivity in the US are in fact specimens of Chamaeleo calyptratus calyptratus. This is evident by the fact that none match Chamaeleo calyptratus calcarifer morphologically. CITES Trade Database statistics support this fact by showing that Saudi Arabia (where Chamaeleo calyptratus calcarifer is found) has never exported the species (UNEP-WCMC 2016). Chamaeleo calyptratus founder populations, on the other hand, originated from exports from Yemen (where Chamaeleo calyptratus calyptratus is found) in the 80s and 90s (UNEP-WCMC 2016).
So, despite claims to the contrary by some individuals, there are no Chamaeleo calyptratus calcarifer currently kept in captivity in the US and photos usually posted purporting to represent this subspecies do not match the subspecies morphological in any way. All captive specimens photographed and posted that I'm aware of represent Chamaeleo calyptratus calyptratus, just like every other veiled chameleon in the trade.
Hope that helps!
Chris
