degree of rigidity. Torso and tail There are 12 dorsal (torso) vertebrae, which are smaller and less specialised than the cervicals. Though their neural spines are taller than those of the cervicals, they are still usually rather short. The dorsal ribs are double-headed close to the shoulder and single-headed in the rest of the torso, sitting on stout transverse processes in the front half of each vertebra. More than 20 angled rows of gastralia extend along the belly, each gastral element represented by a pair of segmented rods which intermingle at the midline. The two sacral (hip) vertebrae are low but robust, bridging over to the hip with expanded sacral ribs. The latter sacral rib is a single unit without a bifurcated structure. The tail is long, with at least 30 and possible up to 50 caudal vertebrae. The first few caudals are large, with closely interlinked zygapophyses and widely projecting pleurapophyses (transverse processes without ribs). The length of the pleurapophyses decreases until they disappear between the eighth and thirteenth caudal. The height of the neural spines also decreases gradually down the tail. A row of long chevrons is present under a short portion of the tail, though not immediately behind the hips. Shoulder and forelimbs The pectoral girdle (shoulder girdle) has a fairly standard form shared with other tanystropheids. The clavicles (collarbones) were curved and slightly twisted rods. They along the front edge of the interclavicle, a plate-like bone at the center of the chest with a rhombic (broad, diamond-shaped) front region followed by a long stalk at the rear. The interclavicle is rarely preserved and its connections to the rest of the pectoral girdle are mostly inferred from Macrocnemus. The scapula (upper shoulder blade) has the form of a large semicircular plate on a short, broad stalk. It lies above, the coracoid (lower shoulder blade), which is a large oval-shaped plate with a broad glenoid facet (shoulder socket). The humerus (upper arm bone) is straight and slightly constricted at the middle. Near the elbow it is expanded and twisted, with ectepicondylar groove on its outer edge. The radius (outer forearm bone) is slender and somewhat curved, while the ulna (inner forearm bone) is similar in shape to the humerus and lacks a distinct olecranon (elbow projection). There are four carpals (wrist bones): the ulnare, radiale, and two distal carpals. The ulnare and radiale are large and cuboid, enclosing