zoocreation


monitor lizards
After the flood



Chad Arment (2025)





Varanus niloticus (CC BY-NC 4.0 Bart Wursten)



The monitor lizards (family Varanidae) are widespread in the Old World, represented by a single extant genus (Varanus) with at least 89 living species and almost a dozen from the fossil record. They inhabit habitats from deserts to rainforests, ranging throughout most of Africa, the Middle East and central Asia, southern and southeast Asia, through much of Australasia. From the Miocene to Pleistocene, monitor lizards were also found in Europe (Villa et al. 2018). Most are carnivorous and prey on smaller animals, though a few species are frugivorous. Some species are small, such as the eight-inch-long Varanus brevicauda, while the male Komodo dragon, Varanus komodoensis, reaches up to 10 feet in length. The giant Australian Pleistocene fossil varanid ‘Megalania,’ Varanus priscus, may have reached up to 23 feet in length.


The Varanidae has been included alongside several other families and a few unplaced genera within the superfamily Varanoidea. While that grouping has changed a bit over time (Helodermatidae is no longer considered part of the varanoids), the only other living family is the Lanthanotidae, comprised of a single species, the Borneo earless monitor, Lanthanotus borneensis, with no fossil history. The secular model suggests a Cretaceous divergence between these two families. The monotypic family Pachyvaranidae (Pachyvaranus) is known from Cretaceous deposits, along with unplaced genera Arcanosaurus, Dryadiisector, and Judeasaurus. The family Palaeovaranidae (three genera) is known from Eocene deposits in Germany and France.


Within the creation model, the Varanoidea could a larger baraminic lineage (created kind), the Varanidae could be a completely distinct baraminic lineage, or the Varanidae and Lanthanotidae could comprise a baraminic lineage separate from the Eocene Palaeovaranidae and additional Cretacous taxa. There are no fundamental logical contradictions to any of these options with the fossil data currently known. If a fossil member of the Lanthanotidae were to be discovered in Cretaceous deposits, however, that would support the idea that the two families are separate created kinds. (The Cretaceous fossil genus Cherminotus was once placed within the Lanthotidae, but has since been removed.) At present, it is possible that the Lanthanotidae diverged from the Varanidae very early after the Flood. It would be interesting to see morphological comparisons between Lanthanotus and the Cretaceous varanids. Rieppel (1980) only compared Lanthanotus with the Eocene Saniwa (“. . . shows [Saniwa] to be more advanced than Lanthanotus in many respects: Saniwa resembles Varanus more closely than it does Lanthanotus”), and with the Eocene Palaeovaranus (“Palaeovaranus differs as much from Varanus as it does from Lanthanotus”).


Within the Varanidae, numerous genera are known from only Cretaceous deposits, suggesting that monitor lizards were particularly diverse before the Flood. This also tells us that even if the monitor lizard’s created kind incorporated other families and genera before the Flood, only a single pair from the Varanidae itself was on the Ark.


It is also notable that Cretaceous varanids were small (Ovoo gurval was about the size of our smallest living varanid, Varanus brevicauda) (Norell et al. 2007), so the pair on the Ark may not have been very large lizards. Post-Flood diversification would be responsible for the larger sizes seen today. The earliest ‘giant’ monitor lizard comes from Miocene Greece deposits (Conrad et al. 2012), which was just a little smaller than the Nile monitor, Varanus niloticus.


Within the secular model, varanids are (usually) believed to have evolved in Asia, then to have spread from there, very early, to both Africa and Australia (Vidal et al. 2012). This compares well with the creation model, where a pair of varanids on the Ark dispersed from the Middle East, likely into Asia, leading to divergence into two recognizable trajectories: Saniwa and Archaeovaranus-Varanus. From the latter, modern Varanus dispersed widely into Africa, Europe, and Australia.



The Varanidae Before and After the Flood



Saniwa



Saniwa is considered a “sister taxon to crown-group Varanus” (Conrad et al. 2008). Branches from Asia appear to have moved into both North America and Europe. Typically monitor-like in appearance, it nonetheless had one significant difference. In tuataras and certain lizards, there is a ‘third eye’ (parietal eye) developing on the top of the skull from the parapineal organ that is functionally photosensory. In Saniwa, this was enhanced, with evidence suggesting both a ‘third eye’ and ‘fourth eye’ present, developing from both the pineal and parapineal organs (Smith et al. 2018).


Saniwa fossils are known from: Paleocene: cf. Saniwa, Swain Quarry, Fort Union Formation, Wyoming (Sullivan 1982); Earliest Eocene: Saniwa sp., Castle Gardens Local Fauna, Willwood Formation, Bighorn Basin, Wyoming [“earliest certain occurrence of Varanus-like varanoids in North America”] (Smith 2009); Early Eocene: Saniwa ensidens, San José Formation, San Juan Basin, New Mexico (Sullivan and Lucas 1988); Saniwa orsmaelensis, Dormaal, Belgium (Augé et al. 2022); Saniwa orsmaelensis, Paris Basin (Avenay, Le Quesnoy, Pourcy, etc.), France (Augé et al. 2022); Late Early Eocene: Fossil Butte Member, Green River Formation, Wyoming (Rieppel and Grande 2007); Middle Eocene: Saniwa ensidens, Bridger Formation, Sweetwater County, Wyoming (Gilmore 1922); Saniwa sp., Mongolia (Dong et al. 2022); Late Middle Eocene: Uinta Formation, Unita Basin, Utah (Sandau 2005); Late Eocene: Saniwa edura, Chalky Buttes Member, Chadron Formation, North Dakota (Smith 2006).


The Saniwa branch died out, unfortunately, leaving no modern-day descendants.



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Megalania (Varanus priscus) replica skull

(CC BY-SA 4.0 Steven G. Johnson)



Varanus salvator, skeleton

(CC BY-SA 3.0 Amada44)



Archaeovaranus-varanus



The recent description of an Eocene varanid in China offers a possible fossil root in Asia for the origin of the Varanus branch. Archaeovaranus was discovered in the early Eocene Yuhuangding Formation, Dajian locality, Liguanqiao Basin, China (Dong et al. 2022). The authors note, “Archaeovaranus resembles Varanus and differs from Saniwa in several features that support its sister group relationship”, though Archaeovaranus demonstrates a more ‘primitive’ state from Varanus in several respects.


There are several other early sites with varanid fossils possibly relevant to this branch, but which are as yet indeterminate. These include:


Eocene North America: Varanidae indeterminate, Eureka Sound Formation, Ellesmere Island, Canadian Arctic Archipelago (Estes and Hutchison 1980)


Eocene-Oligocene Africa: Varanid vertebrae, Birket Qarun Formation, Egypt (Holmes et al. 2010; Ivanov et al. 2017; Augé and Guével 2018); Varanidae indeterminate, Yale Quarry I, Jebel Qatrani Formation (early Oligocene), Fayum Province, Egypt (Smith et al. 2008)



The confirmable Varanus fossil record demonstrates an early dispersion throughout several continents. A sampling of fossil sites includes:


Miocene Asia: Varanus sp. in Kazakhstan, Ukraine, and Moldova (Ivanov et al. 2017); Varanus sp., likely the Chinji Formation, Siwaliks, Pakistan (Villa and Delfino 2022); Varanus sp. in Jradzor, Armenia, and Tetri Udabno, Georgia (Vasilyan and Bukhsianidze 2020); Varanus sp. in Russia (Messinian) and Moldova (Tortonian) (Vasilyan and Bukhsianidze 2020)


Pliocene-Pleistocene Asia: Varanus sivalensis, Siwalik Hills, India (Ivanov et al. 2017)


Pleistocene Asia: Varanus sp., Raebia, Timor (Hooijer 1972); Varanus komodoensis, Ola Bula Formation, Flores (Hocknull et al. 2009); Varanus cf. komodoensis, Kedung Brubus, Java (Hocknull et al. 2009); Varanus salvator, Trinil, Java (Hocknull et al. 2009); Varanus sp., Doi Pha Kan, Thailand (Bochaton et al. 2019)


Miocene Europe: Varanus marathonensis, Mytilini Formation (Turolian), Samos, Greece (Conrad et al. 2012; Villa et al. 2018); Varanus sp., Chomateri Member, Pikermi Formation, Pikermi, Greece (Georgalis 2019); Varanus sp., Lower Continental Complex, Vallès-Penedès Basin, CMA, Can Mas, Spain (Delfino et al. 2013); ?Varanus sp., Eimätteli Member, Napf Formation, Hüenerbach, Switzerland (Georgalis et al. 2023); Varanus sp., Artenay (MN4), Loire Basin, France (Augé and Guével 2018); Varanus mokrensis, Mokrá-Western Quarry (Ottnangian), Czech Republic (Ivanov et al. 2017); Varanus sp., Petersbuch 2, Germany (Ivanov et al. 2017); Varanus sp., Gratkorn, Austria (Ivanov et al. 2017); Varanus sp. in Italy (Messinian) (Vasilyan and Bukhsianidze 2020)


Pliocene Europe: Varanus sp., Moreda, Spain (Villa et al. 2018); Varanus marathonensis, Gonia Formation, Megalo Emvolon, Greece (Drakopoulou et al. 2022); Varanus sp., Çeştepe, Kazan Basin, Anatolia, Turkey (Sen et al. 2017)


Pleistocene Europe: Varanus sp., Tourkobounia 5 (Middle Pleistocene), near Athens, Greece (Georgalis et al. 2017).


Miocene Africa: Varanus rusingensis, Kiakanga Hill, Grit Member of the Hiwegi Formation, Rusinga Island, Kenya (Clos 1995; Ivanov et al. 2017); Varanus sp., Uganda (Rage 2003); Varanus sp., Arrisdrift (Orleanian), Namibia (Rage 2003); Varanus sp., Moghra Formation (Burdigalian), Western Desert, Egypt (Georgalis et al. 2020)


Pliocene Africa: Varanus cf. niloticus + exanthematicus, Kanapoi, Kenya (Head and Müller 2020)


Pleistocene Africa: Varanus cf. niloticus, Plovers Lake, Gauteng Province, South Africa (De Ruiter, D. J., et al. 2008)


Miocene Australia: Varanus sp., Ngapakaldi Local Fauna, Etadunna Formation, Lake Eyre Basin (Scanlon 2014; Georgalis et al. 2020); Varanus sp., Hiatus and White Hunter localities, Riversleigh (Scanlon 2014; Georgalis et al. 2020); Camfield Beds, Bullock Creek, Northern Territory (Scanlon 2014); Alcoota Local Fauna, Northern Territory (Scanlon 2014)


Pliocene Australia: Varanus komodoensis, Bluff Downs Local Fauna and Chinchilla Sands Local Fauna, Queensland (Hocknull et al. 2009)


Pleistocene Australia: Varanus komodoensis, Mt. Etna Local Fauna and Marmor Quarry, Queensland (Hocknull et al. 2009); Varanus [Megalania] priscus, Naracoorte, South Australia (Scanlon 2014); Varanus [Megalania] priscus, Darling Downs, Queensland (Scanlon 2014)



Distinct clades of Varanus species groups emerged early (Vidal et al. 2012). Eleven subgenera have been described. The specific impetus for diversification (biotic or abiotic factors such as geographic barriers or niche competition) likely varies by clade (Pavón-Vázquez et al. 2022).


Extreme gigantism is found in one Australasian Varanus clade, which produced three oversized monitor lizards: the fossil Megalania (now Varanus priscus), the Komodo dragon (Varanus komodoensis), and an as-yet-undescribed Varanus fossil species on Timor. In the past, the Komodo dragon was thought to be an example of insular gigantism, as sometimes an organism will grow larger in smaller, isolated populations. Now, the evidence supports an Australian origin, with the species spreading into Indonesia, and now only surviving on the Komodo islands (Hocknull et al. 2009). Megalania was a much larger lizard, and studies show that it was able to reach greater lengths by delaying maturity and thus prolonging juvenile growth rates for a longer length of time (Erickson et al. 2003). Komodo dragons have vicious bites (and iron-coated, serrated, curved-blade teeth) backed up by venom glands (LeBlanc et al. 2024; Janeczek et al. 2025), making them formidable predators. Megalania is believed to have had similar venom glands, making it the largest venomous animal ever (Fry et al. 2009).



Varanus albigularis microstictus
black-throated monitor





(CC BY-NC 4.0 David Williams)



Varanus salvadorii
Crocodile monitor





(CC BY-NC 4.0 Chris Barnes)



Varanus prasinus
emerald tree monitor





(CC BY-NC 4.0 David Mules)



varanus nebulosus
clouded monitor





(CC BY-NC-ND 2.0 Budak)



Varanus tristis
freckled monitor





(CC BY-NC-ND 2.0 Bill Higham)



varanus griseus
desert monitor





(CC BY-NC-ND 2.0 Alexandre Roux)



varanus varius
lace monitor





(CC BY-NC-SA 2.0 Leo)



varanus gouldii
gould's sand monitor





(CC BY 2.0 Jean and Fred Hort)



varanus komodoensis
komodo dragon





(CC BY 2.0 Adhi Rachdian)



references



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