Fig 1.
Complete articulated skeleton of a neonate of Chelus orinocensis (ID 13, Straight Carapace Length, SCL= 69.9 mm).
Fig 2.
Skull of a Chelus orinocensis neonate (ID 13, SCL = 69.3 mm).
A. rostral. B. lateral. C. dorsal D. ventral. E. caudal views of the skull. Bocc: basioccipital; Bsph: basisphenoid; Exocc: exoccipital; Fr: frontal; J: jugal; Max: maxilla; Opot: opisthotic; Par: parietal; Plt: palatine; Porb: postorbital; PrFr: prefrontal; PrMax: premaxilla; Proo: prootic; Pter: pterygoid; Qua: quadrate; Socc: supracoccipital; Squ: squamosal; Vo: vomer. Black lines were added to the figures to delineate the bone sutures.
Fig 3.
Mandible of a Chelus orinocensis neonate (ID 20, SCL = 80.3 mm).
A. Mandible disassembled in dorsal view. B. Mandible complete in dorsal view. The angular bone fig 3A on the left side is detached.
Fig 4.
Hyoid apparatus of a Chelus orinocensis neonate.
A. Hyoid apparatus in dorsal view, B. Ventral view in individual ID 20 (SCL = 80.3 mm). C. Hyoid apparatus disassembled in individual ID 11 (SCL = 72.58 mm) in ventral view to expose each bone individually.
Fig 5.
Structures of cervical vertebra 7 (C7) of a Chelus orinocensis neonate (ID 20, SCL = 80.3 mm), oblique view.
Fig 6.
Cervical vertebrae of a Chelus orinocensis neonate in lateral, cranial, oblique and caudal views.
Fig 7.
Carapace and plastron of Chelus orinocensis neonates.
A.Carapace in dorsal view indicating the dermal bones in individual ID 63 (SCL = 76.07 mm). B. Carapace in ventral view in individual ID 11 (SCL = 72.58 mm). C, D. Plastron in dorsal and ventral views respectively in individual ID 11. Incomplete growth of dermal bones results in the presence of fontanelles in carapace and plastron.
Fig 8.
Dermal bones of the plastron disassembled in a Chelus orinocensis neonate (ID 20, SCL = 80.3 mm), in dorsal view.
Fig 9.
Right pectoral girdle of a Chelus orinocensis neonate (ID 20, SCL = 80.3 mm), shown in dorsal view.
Fig 10.
Forelimb (left side) of Chelus orinocensis neonate (ID 20, SCL = 80.3 mm, shown in dorsal view. CCI: central carpal I; CCII: central carpal II; CI: carpal I; CII: carpal II; CIII: carpal III; CIV: carpal IV; InC: intermediate carpal; MCI: metacarpal I; MCII: metacarpal II; MCIII: metacarpal III; MCIV: metacarpal IV; MCV: metacarpal V; PI: phalange I; PII: phalange II; PIII: phalange III; UC: ulnar carpal. Digit 1 is missing the distal phalange, digit 2 is missing its claw.
Fig 11.
Pelvic girdle (left side) of a Chelus orinocensis neonate (ID 20, SCL = 80.3 mm).
A. Medial view, B. Cranial view, C. Lateral view.
Fig 12.
Hindlimb (right side) of a Chelus orinocensis neonate (ID 20, SCL = 80.3 mm). A. Femur in cranial view, B. Femur in caudal view, C. Distal hindlimb in dorsal view. C: central tarsal TIII: tarsal III; TIV: tarsal IV; MTI: metatarsal I; MTII: metatarsal II; MTIII: metatarsal III; MTIV: metatarsal IV; MTV: metatarsal V (hooked bone); PI: phalange I; PII: phalange II; PIII: phalange III. Digit 4 is missing the distal phalange and its claw.