P, impression. F. CGH256, scapula; bone. Cb, clavicle blade; Gl?, glenoid fossa?; Hum, humerus; Intc, interclavicle; Sc, scapula. Scale bars = 1mm. doi:10.1371/journal.pone.0128333.gfigure 82A, as MB 1898.67), although only part of the endochondral girdle was actually illustrated. There is a flaw in the cast, but observation of the original buy ARA290 specimen shows the true size and shape of what is either one large scapula with a crack qhw.v5i4.5120 at bmjopen-2015-010112 the center, or a scapula plus coracoid (Fig 17E). There is continuous ornamentation or pitting located along the curved edges of the two halves and together the pieces contribute to the glenoid, surrounding the proximal humerus, which demonstrates that the pieces form one functional unit, whether scapula or scapula-coracoid. Another of the largest individuals (CGH256; based on 3mm centrum length) mayPLOS ONE | DOI:10.1371/journal.pone.0128333 June 17,27 /Skeletal Morphogenesis of order Peretinoin Microbrachis and Hyloplesionpossess only the portion of the coracoid that immediately contributes to the glenoid, although the bone in that area is poorly ossified, leading to some doubt (Fig 17F). The `scapula’ and `cleithrum’ figured and described by Steen ([46] reference figure 19E) do not conform with the morphology observed in other specimens and were probably misidentified. The entepicondylar foramen of the humerus, which is a prominent, large, oval slit in M. pelikani, is visible only in ventral (flexor) view. It is present in individuals of all sizes when the humerus is preserved in the appropriate orientation (Table 1). In the smallest specimens, the humerus is a simple, straight column of bone with an unwaisted shaft, unfinished ends with flat surfaces, and no processes (Fig 18A). At this stage of development, there also is no torsion. In the next stage of morphogenesis, the shaft of the humerus becomes distinct from the proximal and distal ends, which are more rounded than in the less developed humeri (Fig 18B). Later, the subcoracoscapularis attachment point begins to form slightly ahead of the deltopectoral crest, and a low degree of torsion ( 30?5? is present between the distal and proximal ends. During early stages of development of the deltopectoral crest, the structure is small, rounded, and located close to the proximal head (Fig 18C). Next, the humerus exhibits preliminary differentiation of the distal condyles (Fig 18D). In smaller individuals, differentiation of the condyles begins as an asymmetric shape-change of the distal shaft, which extends further on the ectepicondylar (radial) side. Torsion may reach 90?in some specimens at this point of development, although others show less twisting. During the next stage of morphogenesis, the deltopectoral crest becomes more prominent, assuming an angular appearance, and is shifted distally, whereas the distal condyles become even more distinct, often via development of a shallow fossa in between the condyles (Fig 18E). Once the condyles and processes are fully developed, torsion is almost always 90? Throughout the growth of the humerus, the proximal head becomes progressively more round (convex). Sequence variation exists and many specimens have not yet developed structures that are clearly visible in smaller specimens. In other words, those larger individuals are at an earlier stage of morphogenetic development [16]. Additionally, one specimen shows evidence of left-right asymmetry in the degree of development of the humerus, although some of the disparity is likely cau.P, impression. F. CGH256, scapula; bone. Cb, clavicle blade; Gl?, glenoid fossa?; Hum, humerus; Intc, interclavicle; Sc, scapula. Scale bars = 1mm. doi:10.1371/journal.pone.0128333.gfigure 82A, as MB 1898.67), although only part of the endochondral girdle was actually illustrated. There is a flaw in the cast, but observation of the original specimen shows the true size and shape of what is either one large scapula with a crack qhw.v5i4.5120 at bmjopen-2015-010112 the center, or a scapula plus coracoid (Fig 17E). There is continuous ornamentation or pitting located along the curved edges of the two halves and together the pieces contribute to the glenoid, surrounding the proximal humerus, which demonstrates that the pieces form one functional unit, whether scapula or scapula-coracoid. Another of the largest individuals (CGH256; based on 3mm centrum length) mayPLOS ONE | DOI:10.1371/journal.pone.0128333 June 17,27 /Skeletal Morphogenesis of Microbrachis and Hyloplesionpossess only the portion of the coracoid that immediately contributes to the glenoid, although the bone in that area is poorly ossified, leading to some doubt (Fig 17F). The `scapula’ and `cleithrum’ figured and described by Steen ([46] reference figure 19E) do not conform with the morphology observed in other specimens and were probably misidentified. The entepicondylar foramen of the humerus, which is a prominent, large, oval slit in M. pelikani, is visible only in ventral (flexor) view. It is present in individuals of all sizes when the humerus is preserved in the appropriate orientation (Table 1). In the smallest specimens, the humerus is a simple, straight column of bone with an unwaisted shaft, unfinished ends with flat surfaces, and no processes (Fig 18A). At this stage of development, there also is no torsion. In the next stage of morphogenesis, the shaft of the humerus becomes distinct from the proximal and distal ends, which are more rounded than in the less developed humeri (Fig 18B). Later, the subcoracoscapularis attachment point begins to form slightly ahead of the deltopectoral crest, and a low degree of torsion ( 30?5? is present between the distal and proximal ends. During early stages of development of the deltopectoral crest, the structure is small, rounded, and located close to the proximal head (Fig 18C). Next, the humerus exhibits preliminary differentiation of the distal condyles (Fig 18D). In smaller individuals, differentiation of the condyles begins as an asymmetric shape-change of the distal shaft, which extends further on the ectepicondylar (radial) side. Torsion may reach 90?in some specimens at this point of development, although others show less twisting. During the next stage of morphogenesis, the deltopectoral crest becomes more prominent, assuming an angular appearance, and is shifted distally, whereas the distal condyles become even more distinct, often via development of a shallow fossa in between the condyles (Fig 18E). Once the condyles and processes are fully developed, torsion is almost always 90? Throughout the growth of the humerus, the proximal head becomes progressively more round (convex). Sequence variation exists and many specimens have not yet developed structures that are clearly visible in smaller specimens. In other words, those larger individuals are at an earlier stage of morphogenetic development [16]. Additionally, one specimen shows evidence of left-right asymmetry in the degree of development of the humerus, although some of the disparity is likely cau.
