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Hajar | profile | all galleries >> Amber Galleries >> Cretaceous Amber Lizard tree view | thumbnails | slideshow

Cretaceous Amber Lizard

There was a lot of excitement around lizards in amber during 2015, with Sherratt et al. (2015) publishing on a group of 20 anoles in Miocene Dominican amber. The complete Cretaceous lizard in Myanmar amber shown here is at least five times as old as the Dominican Republic material.

Previously described Cretaceous material includes tiny fragments of reptile skin (AMNH Bu337), a fragment (tail and right hind foot) of a lizard (Baabdasaurus) in Lebanese Cretaceous amber, and the foot of a gecko (Cretaceogekko burmae) in Burmese amber (Arnold & Poinar 2008). The individual shown here (RS.P.1428 in my catalogue) is 3 cm long. The innards have mostly decomposed, with the exception of the limb bones, but the external form, with fine detail of the scales, is complete, from snout to tip of tail. Preservation of the feet is exquisite, even showing the sharp little claws. The tail bears larger and more robust scales than the body. Scales have multicarinate ornament.

Complete lizards in amber of any age are far from common: 9 from the Dominican Republic Miocene (Anolis, Sherratt et al. 2015), 1 near complete from the Miocene of Chiapas (Anolis, Carbot-Chanona & Milani 2008), 2 near complete from the Baltic Eocene (Succinilacerta succinea, Borsuk-Bialynicka et al. 1999), and this one from the Cretaceous.

There is now a paper by Daza et al. (2016) published on the diversity of mid Cretaceous lizards in the Myanmar amber: http://advances.sciencemag.org/content/2/3/e1501080.full

The complete specimen illustrated here appears to be an example of the form shown in Fig. 2A in the paper. It is described as displaying "many plesiomorphic squamate characters (for example, notochordal vertebral centrum and paired premaxillae), although [there are] some similarities with scincomorphs, including integumentary and osteological features." CT scans of this specimen reveal excpetionally detailed preservation of the limbs, even including the patellas. See: https://www.earthtouchnews.com/discoveries/fossils/fossil-forensics-two-ancient-lizards-two-amber-encased-mysteries/

Acquired in 2015, I visited the UT Austin CT lab (driving over from Houston) with the specimen in January 2016 in order to acquire a micro CT image of the lizard and associated invertebrates. Scientific analysis of the animal has subsequently been completed by Juan Daza and his team at Sam Houston State University, Texas.
Ventral view of complete 3 cm juvenile lizard (stem squamate, Daza et al. 2016). Ventral view. Notice the detailed impressions of scales in the integument, increasingly robust in the tail. Head and forelimbs
Head, showing scales and eye, seen from beneath. Front left foot Front left foot. Notice also the pattern of scales on the body.
Front right foot. Notice also the humerus. Rear left foot. Notice the wonderfully preserved claws. Larger scales are present on the tail.
Larger scales are present on the tail. A detail showing the multicarinate scales. A detail of multicarinate scales on dorsal surface of the head.
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