The imagery on this page was the basis for a paper entitled Cranial anatomy of the spade-headed amphisbaenian Diplometopon zarudnyi (Squamata, Amphisbaenia) based on high-resolution X-ray computed tomography, by J. A. Maisano, M. Kearney and T. Rowe (Journal of Morphology 267:70-102, 2006). The abstract is as follows:

       The skull of the trogonophid amphisbaenian Diplometopon zarudnyi is described from high-resolution         X-ray computed tomographic (HRXCT) imagery of a whole museum specimen preserved in ETOH. The         skull was digitally resliced and disarticulated into individual elements (see Additional Imagery),        producing novel visualizations that allow detailed morphological analysis of its three-dimensionally        complex structure. The prefrontal and jugal are absent in Diplometopon. The septomaxilla is present        but hidden entirely from superficial view. In contrast to previous studies, we recognize a splenial        fused to the compound bone of the mandible and a squamosal fused to the otic-occipital complex.        Comparison of Diplometopon to the two other amphisbaenians previously described in comparable        detail, Rhineura hatcherii and Amphisbaena alba, reveals a mosaic of cranial similarities and        differences. Both Diplometopon and Rhineura exhibit a craniofacial angulation and expanded rostral        blade related to use of the head as a digging tool, but the detailed architecture of these features is        quite different. Additionally, whereas the snout of Rhineura exhibits a high degree of sculpturing and        sensory innervation, this is not the case in Diplometopon. Unlike in Rhineura and Amphisbaena, the        cranial elements of Diplometopon do not exhibit an extensive degree of overlap or complex        interlocking sutures; instead, most of the cranial elements lie in loose apposition to each other. The        degree to which this mosaic of features reflects functional demands, shared ancestry, and/or        convergence is unclear in the absence of a stable hypothesis of amphisbaenian phylogeny.

DigiMorph Account of Diplometopon

Additional images of Diplometopon zarudnyi were sent to DigiMorph by Danny Fidler of the United States Air Force. The photos were taken May 28, 2004 around 11 pm in the vicinity of Umm Qasr in southern Iraq. Staff Sargent Fiddler described the behavior as follows:

"Last night I found two worm lizards while I was doing my rounds. I believe they were mating as you can see by the pictures. However I am not sure. ... When the larger of the two was done doing whatever it was it was doing, it released the smaller one. However they were facing each other 'head-to-toe' in the photos. Instead of them grasping each other by what I thought was there genitalia, the larger ones jaw was grasping the bottom portion of the smaller one. And on a few photos, you can see where the last few centimeters of the smaller lizard appeared to be sunken in a bit along the spine, almost like the larger one was sucking fluids from it."

This specimen was collected from Qatif Oasis, Saudi Arabia by E. Murray in 1948. It was made available to the University of Texas High-Resolution X-ray CT Facility for scanning by Dr. Jessie Maisano of The University of Texas and Dr. Maureen Kearney of the Field Museum of Natural History. Funding for scanning was provided by a National Science Foundation Digital Libraries Initiative grant to Dr. Timothy Rowe of The University of Texas at Austin. Funding was also provided by a National Science Foundation Assembling the Tree of Life grant (EF-0334961), The Deep Scaly Project: Resolving Squamate Phylogeny using Genomic and Morphological Approaches, to Drs. Jacques Gauthier of Yale University, Maureen Kearney of the Field Museum, Mike Lee of the University of Adelaide, Jessie Maisano of The University of Texas at Austin, Tod Reeder of San Diego State University, Olivier Rieppel of the Field Museum, Jack Sites of Brigham Young University, and John Wiens of SUNY Stonybrook.

Dorsal view of specimen	Lateral view of head	Dorsal view of head

The specimen was scanned by Richard Ketcham on 11 February 2003 obliquely along the coronal axis for a total of 459 slices, each slice 0.0192 mm thick with an interslice spacing of 0.0192 mm.

Literature

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Links

Trogonophidae page from the EMBL Reptile Database

Three-dimensional volumetric renderings of isolated cranial bones. Movies are 1 mb or less unless otherwise noted.

skull roll movie (2mb)	skull yaw movie (2mb)	skull pitch movie (2mb)
premaxilla roll movie	premaxilla yaw movie	premaxilla pitch movie
septomaxilla roll movie	septomaxilla yaw movie	septomaxilla pitch movie
maxilla roll movie	maxilla yaw movie	maxilla pitch movie
nasal roll movie	nasal yaw movie	nasal pitch movie
vomer roll movie	vomer yaw movie	vomer pitch movie
palatine roll movie	palatine yaw movie	palatine pitch movie
ectopterygoid roll movie	ectopterygoid yaw movie	ectopterygoid pitch movie
pterygoid roll movie	pterygoid yaw movie	pterygoid pitch movie
frontal roll movie	frontal yaw movie	frontal pitch movie
parietal roll movie (2mb)	parietal yaw movie	parietal pitch movie
otic-occipital roll movie	otic-occipital yaw movie (2mb)	otic-occipital pitch movie (2mb)
orbitosphenoid roll movie	orbitosphenoid yaw movie	orbitosphenoid pitch movie
quadrate roll movie	quadrate yaw movie	quadrate pitch movie
stapes roll movie	stapes yaw movie	stapes pitch movie
extracolumella roll movie	extracolumella yaw movie	extracolumella pitch movie
mandible roll movie	mandible yaw movie	mandible pitch movie
dentary roll movie	dentary yaw movie	dentary pitch movie
coronoid roll movie	coronoid yaw movie	coronoid pitch movie
compound bone roll movie	compound bone yaw movie	compound bone pitch movie
hyoid roll movie	hyoid yaw movie	hyoid pitch movie