TABLE 1. Measurements of skeletal elements of referred specimens of Kupoupou stilwelli n. gen. et sp. Refer to Figure 2 and Figure A2 for relating numerals associated with each cervical vertebra to images of their corresponding element.
| Specimen/Element | Measurement distance | Measurement (mm) |
| NMNZ S.44729/Coracoid | Maximum omal-sternal length | 91.4 |
| Maximum omal-sternal distance of sulcus musculi supracoracoidei | 12.1 | |
| Maximum diameter of scapular condyle | 7.7 | |
| NMNZ S.47303/Carpometacarpus | Total length | 31.9 |
| Distal craniocaudal width | 11.73 | |
| Distal dorsoventral depth | 4.16 | |
| NMNZ S.47303/Left radius | Total proximodistal length | 69.16 |
| Proximal craniocaudal width | 7.33 | |
| Mid-shaft craniocaudal width | 6.38 | |
| Proximal dorsoventral depth | 4.61 | |
| Mid-shaft dorsoventral depth | 3.35 | |
| Distance from cotylaris humeralis to bend on cranial margin | 24.82 | |
| NMNZ S.47303/Right radius (broken) | Total proximodistal length (broken) | 41.91 |
| Proximal craniocaudal width | 7.06 | |
| Mid-shaft craniocaudal width | 7.58 | |
| Proximal dorsoventral depth | 5.75 | |
| Mid-shaft dorsoventral depth | 3.3 | |
| Distance from cotylaris humeralis to bend on cranial margin | 17.5 | |
| NMNZ S.47303/Manus phalanx II-1 | Total length | 24.14 |
| Proximal craniocaudal width | 6.54 | |
| Proximal dorsoventral depth | 3.66 | |
| Distal craniocaudal width | 5.05 | |
| Distal dorsoventral depth | 1.85 | |
| Maximum craniocaudal width | 8.51 | |
| NMNZ S.47303/Manus phalanx III-1 | Total length | 13.17 |
| Proximal facet craniocaudal width | 4.3 | |
| Proximal facet dorsoventral depth | 3.75 | |
| Mid-shaft craniocaudal width | 4.65 | |
| NMNZ S.47303/Axis | Craniocaudal length of neural canal | 12.28 |
| Lateral diameter of neural canal | 5.5 | |
| Total distance between tips of ventral process and neural spine | 25.9 | |
| NMNZ S.47303/Cervical (i) | Craniocaudal length of neural canal | 13.9 |
| Lateral diameter of neural canal | 7.14 | |
| Total distance between tips of ventral process and neural spine | 23.42 | |
| NMNZ S.47303/Cervical (ii) | Craniocaudal length of neural canal | 19.07 |
| Maximum lateral width between caudal zygapophyses | 17.99 | |
| Maximum lateral width between cranial zygapophyses | 14.1 | |
| NMNZ S.47303/Cervical (iii) | Craniocaudal length of neural canal | 17.45 |
| Lateral diameter of neural canal | 7.27 | |
| Maximum lateral width between cranial zygapophyses | 18.15 | |
| NMNZ S.47303/Cervical (iv) | Craniocaudal length of neural canal | 16.8 |
| Lateral diameter of neural canal | 7.95 | |
| Maximum lateral width between cranial zygapophyses | 24.47 | |
| Maximum lateral width between caudal zygapophyses | 24 | |
| NMNZ S.47303/Caudal vertebra | Lateral diameter of centrum/corpus | 7.34 |
| Maximum lateral width | 13.89 | |
| Maximum dorsoventral height | 15.57 | |
| Maximum craniocaudal length of centrum/corpus | 7.45 | |
| NMNZ S.47303/Rib | Maximum length | 70.42 |
| NMNZ S.47303/Ischium | Maximum craniocaudal length | 41.42 |
| Maximum dorsoventral width | 14.99 | |
| Maximum mediolateral depth | 2.36 | |
| NMNZ S.47308/Femur | Maximum proximodistal length | c. 96.0 |
| Maximum mediolateral width of distal end | 25.7 | |
| Maximum mediolateral width of proximal end | 26.7 | |
| NMNZ S.47308/Humerus | Maximum proximodistal length | 106.8 |
| Mid-shaft craniocaudal width | 13.3 | |
| Maximum craniocaudal width of caput humeri | 20.6 | |
| NMNZ S.47308/Coracoid | Maximum omal-sternal length | - |
| NMNZ S.47308/Ulna | Maximum proximodistal length | 69.9 |
| Proximal craniocaudal width | 22.6 | |
| Proximal dorsoventral depth | 11.0 | |
| Mid-shaft craniocaudal width | 10.5 | |
| Mid-shaft dorsoventral depth | 6.5 | |
| Distal craniocaudal width | 10.0 | |
| NMNZ S.47339/Scapula | Distance from facies articularis humeralis to acromion | 22.0 |
| NMNZ S.47339/Humerus | Maximum proximodistal length | - |
| Mid-shaft craniocaudal width | 14.4 | |
| Maximum craniocaudal width of caput humeri | 18.6 | |
| NMNZ S.47339/Ulna | Maximum proximodistal length | - |
| Proximal craniocaudal width | 22.1 | |
| Proximal dorsoventral depth | 11.3 | |
| Mid-shaft craniocaudal width | 11.0 | |
| Mid-shaft dorsoventral depth | 6.8 | |
| NMNZ S.47339/Radius | Total proximodistal length | 77.3 |
| Proximal craniocaudal width | 8.5 | |
| Mid-shaft craniocaudal width | 8.2 | |
| Proximal dorsoventral depth | 7.1 | |
| Mid-shaft dorsoventral depth | - | |
| Distance from cotylaris humeralis to bend on cranial margin | 16.3 |
TABLE 2. Measurements of skeletal elements of specimens associated with the larger Chatham Island form.
| Specimen/Element | Measurement distance | Measurement (mm) |
| NMNZ S.47302/Mandible | Maximum rostrocaudal length | 45.65 |
| Maximum mediolateral width | 13.23 | |
| Maximum dorsoventral depth | 24.94 | |
| NMNZ S.47302/Furcula | Maximum length of left clavicle from omal end to extremitas sternalis claviculae | 46.99 |
| Distance between omal-most ends of each clavicle | 59.85 | |
| Maximum omal-caudal width | 5.45 | |
| Maximum dorsoventral depth | 11.32 | |
| NMNZ S.47302/Cervical vertebra IV | Length of neural canal | 19.28 |
| Lateral diameter of neural canal | 6.09 | |
| Maximum lateral width between cranial zygapophyses | 25.73 | |
| Maximum lateral width between caudal zygapophyses | 26 | |
| Total distance between tips of ventral process and neural spine | 24.09 | |
| NMNZ S.47302/Coracoid | Diameter of scapular condyle | 8.45 |
| Maximum omal-sternal length | 62.02 | |
| Maximum omal-sternal distance of sulcus musculi supracoracoidei | 29.25 | |
| NMNZ S.47302/Sternum | Maximum length | 24.48 |
| Maximum width | 22.23 | |
| Maximum depth of carina sterni | 6.09 | |
| NMNZ S.47304/Humerus | Maximum proximodistal length | 116.3 |
| Mid-shaft craniocaudal width | 20.0 | |
| Maximum craniocaudal width of caput humeri | 27.0 |
