Morphology of the Sternum, Pectoral Girdle and Wing of West African Black-Crowned Crane (Balearica pavonina pavonina)

Abstract

The present work was undertaken to study the gross morphological features of the sternum, pectoral girdle and wing bones of adult black-crowned  crane. The bones were processed using standard techniques to highlight structural details. The sternum was triangular shaped, comprised of three  borders and two surfaces. The dorsal border was slightly shallow medially having linearly arranged pneumatic foramina. The basal border was strongly  convex and bears a prominent sternal crest. The cranial border was broad and transversely convex with shallow grooves on the lateral edges for  articulation with the coracoid bones. There were seven pairs of ribs that articulated with corresponding sterno-costal bones. The shoulder girdle  comprised of the blade-like scapula, coracoid, and the clavicles which fused proximally to form the foramen triosseum. The humerus was pneumatic  tubular bone with flat expanded proximal ends and small rounded distal ends. The ulna and radius were of comparatively equal length, separated along  their long axis by extended interosseous space. The carpus consisted of the ulnar carpal bone and radial carpal bone. Whereas, the carpo-metacarpal  comprised of three primary bones that articulated distally with corresponding rays of digits.