48
Biology of Sea Turtles, Vol. II
bones of the plastron and limb girdles initially articulate with one another via
cartilage or connective tissue. As cheloniids grow, bone fills in between the ribs,
producing pleural bones that are ankylosed along their abutting borders; the hyoplastron and hypoplastron bones usually fuse by adulthood, as do the bones of the
pelvic and pectoral girdles. Cartilages are found primarily on joint surfaces.
The skeleton of adult leatherbacks remains neotenic in form, with the bones
retaining substantial cartilaginous processes, flexible articulations, and large vascular
cartilages and cartilage-replacement bone on the limb bone ends (Rhodin, 1985).
FIGURE 2.7 The bony carapace of a cheloniid is formed from a composite of bones. These
and key landmarks are shown in dorsal view (A) and ventral view (B). (Adapted from
Wyneken, J. The Anatomy of Sea Turtles, U.S. Department of Commerce, NOAA Technical
Memorandum NMFS-SEFSC-470, 2001. With permission.)
1123_C02.fm Page 48 Friday, November 15, 2002 11:16 AM
Biology of Sea Turtles, Vol. II
bones of the plastron and limb girdles initially articulate with one another via
cartilage or connective tissue. As cheloniids grow, bone fills in between the ribs,
producing pleural bones that are ankylosed along their abutting borders; the hyoplastron and hypoplastron bones usually fuse by adulthood, as do the bones of the
pelvic and pectoral girdles. Cartilages are found primarily on joint surfaces.
The skeleton of adult leatherbacks remains neotenic in form, with the bones
retaining substantial cartilaginous processes, flexible articulations, and large vascular
cartilages and cartilage-replacement bone on the limb bone ends (Rhodin, 1985).
FIGURE 2.7 The bony carapace of a cheloniid is formed from a composite of bones. These
and key landmarks are shown in dorsal view (A) and ventral view (B). (Adapted from
Wyneken, J. The Anatomy of Sea Turtles, U.S. Department of Commerce, NOAA Technical
Memorandum NMFS-SEFSC-470, 2001. With permission.)
1123_C02.fm Page 48 Friday, November 15, 2002 11:16 AM