| Descripción |
Es un hueso recto, de aspecto columnar que mide 1, 3 metros y que esta caracterizado por dos expansiones, una en el extremo proximal (formada por la cabeza femoral) y otra en el extremo distal (formada por la presencia de dos cóndilos, el tibial y el fibular). La diáfisis tiene sección elíptica y presenta bien marcado el cuarto trocánter mediante una cresta y un surco. Sus características son típicas de los dinosaurios saurópodos, pudiendo clasificarse dentro de este grupo en los Titanosauriformes por la presencia de una comba lateral en la el extremo proximal del fémur.
Diagnosis de Tastavinsaurus (Canudo et al., 2008; Royo-Torres et al., 2011)
(1) The caudalmost thoracic vertebra possesses a postspinal process with two small accessory laminae at its base.
(2) The accessory lamina that joins the spinoprezygapophyseal with the spinodiapophyseal or spinopostzygapophyseal laminae bounds an oval depression at the dorsal end of the spinous process in the caudalmost thoracic vertebra.
(3) The sacricostal yoke is ventrolateral to the vertebral bodies.
(4) The sacral ribs are mediolaterally short.
(5) The sacral ribs are separated from the caudosacral vertebral body ventrally by a deep notch.
(6) The first caudal vertebra has a short axial lamina between the postzygapophyses.
(7) The proximal caudal vertebrae have short axial laminae between their prezygapophyses.
(8) There are rounded bumps on both articular faces of the mid-distal caudal vertebrae.
(9) The ischium/pubis length ratio is <0.70.
(10) The angle of the cranioventral corner of the distal extremity of the pubis is acute.
(11) The tibia are short (55% of the length of the femur).
(12) The lateral end of the cnemial crest of the tibia splits into two thin vertical crests separated by a shallow depression.
(13) In profile, the proximal end of the fibula is crescentic.
(14) The cranial trochanter of the fibula is well developed and forms a crest that projects craniomedially.
(15) The distal end of the fibula is subquadrangular.
(16) Metatarsal I has a robustness index value of 1.0 (0.97).
(17) The area of the proximal end of metatarsal II is 30% greater than that of metatarsal I.
(18) Metatarsals I and II both possess pronounced superolateral projections.
(19) The proximal end of metatarsal V is greatly expanded (three times the width of the distal end).
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