Preon Big-Arm Lizard

Megalancosaurus preonensis

    Megalancosaurus preonensis is a megalancosaurid, a bizzare reptile of uncertain affinities.  While one species of megalancosaurid (Hypuronector limnaios)  has adapted to an aquatic exsistance, most megalancosaurids are arboreal.  In M. preonensis, specialization for this particular lifestile has affected this animal's body to an almost gruesome degree.

    M. preonensis's small, bird-like head sits atop a long neck that, when it joins the torso, balloons outward into a large hump. This hump (also present in Drepanosaurus, but to a lesser extent) serves as an attachment to powerful dorsal muscles that run along M. preonensis's back.  M. preonensis's forelimbs terminate in five-clawed "hands" with the inner three fingers opposed to the outer two, creating a powerful clamp with which the creature can anchor itself to tree branches.  Likewise, the hind feet of M. preonensis posses a large "thumb" that opposes the other four digits.  The tail is long, muscular and, to a degree, prehensile and serves as yet another anchor to M. preonensis when it engages in its arboreal perambulations.

Other sites containing pertinent information:

• Megalancosauridae from the Pterosaur Home Page (first article)
• Vertebrate Paleontology's Megalancosaurus page (with lots of information and pictures)