Juravenator starki (Gohlich and Chiappe 2006) Late Jurassic ~150 mya, 70 cm in length, was derived from a sister to Sinocalliopteryx and Sinocalliopteryx and was an ancestor to basal birds, such as its Solnhofen contemporary, Archaeopteryx.
Distinct from Coelophysis the skull of Juravenator was shorter. The anterior teeth were nearly below the naris. A small maxillary fenestra appeared anterior to the antorbital fenestra. The upper jawline notch moved behind the naris and was completely within the maxilla. The upper lacrimal was more robust. The frontal process of the postorbital was smaller. The squamosal was larger. The orbit was larger than the antorbital fenestra. The quadratojugal and the lateral temporal fenestra were both shorter. The jaw was relatively deeper. The teeth were longer and more sharply recurved.
The entire vertebral column was relatively shorter. There were fewer doral vertebrae and ribs. The chevrons were each shorter, butthey continued back further toward the tip of the tail.
The scapula was narrower. The manus was as large as the rest of the forelimb. A distinctly larger pectoral crest was presenton the humerus.
The pubis had rotated more ventrally and was provided with an expanded "boot." The ischium was rotated ventrally, but to a lesser degree.
While Juravenator was covered with scales, there is a slight indication of feather-like strands emanating from the pelvic and hind limb areas of the fossil. |
