= Gymnophthalmidae
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<Gymnophthalmidae> is a family of <lizards> within <Lacertoidea>, often called microteiids. It is distinct from <Teiidae>, despite that historical common name. Its members include forms with fairly conventional limbs and forms with strongly reduced limbs and elongated bodies, making the family useful for studying how a body plan changes during evolution.<Integrated Analyses Resolve Conflicts over Squamate Reptile Phylogeny and Reveal Unexpected Placements for Fossil Taxa by Tod W. Reeder and others>[Results, composition of Lacertoidea]{ref}
A morphological study distinguished modest reductions, such as losing one or two finger or toe bones, from much more extensive reductions that can leave no externally distinct adult limb. The investigators compared digit arrangements and also examined <gene expression> in developing reduced limbs. Adult anatomy and embryonic development consequently provide complementary observations of the same evolutionary problem.<Digit evolution in gymnophthalmid lizards by Juliana G. Roscito and others>[abstract, two groups of reduced limb morphologies and embryonic gene expression]{ref}
For an anatomical example, two feet can each have four visible digits while differing in which digit is absent or in the number of bones within each remaining digit. Merely counting visible toes collapses those possibilities into one score. Recording the detailed bone pattern and placing it on a <phylogenetic tree> gives a more informative test of whether superficially similar reductions share an evolutionary origin.
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