Daniadyptes primaevus, Mayr & De Pietri & Proffitt & Blokland & Clarke & Love & Mannering & Crouch & Reid & Scofield, 2025

Mayr, Gerald, De Pietri, Vanesa L., Proffitt, James, Blokland, Jacob C., Clarke, Julia A., Love, Leigh, Mannering, Al A., Crouch, Erica M., Reid, Catherine & Scofield, R. Paul, 2025, Multiple exceptionally preserved fossils from the Paleocene Waipara Greensand inform the diversity of the oldest stem group Sphenisciformes and the formation of their diving adaptations, Zoological Journal of the Linnean Society 204 (4) : -

Daniadyptes primaevus sp. nov. ( Figs. 2, 11, 12, 14)

ZooBank LSID: urn:lsid:zoobank.org:act:B6FDEC5D-D038-4DA6-B41D-42010686FBB5 .

Holotype: UC 22081 ( Fig. 11Z, AA; right humerus).

Diagnosis: As for genus. The holotype is shorter than the humerus of Kupoupou stilwelli ( Table 1).

Etymology: The species epithet is derived from primus (Lat.): first and aevum (Lat.): age, in reference to the fact that the species is among the oldest known stem group sphenisciforms.

Type locality and horizon: Waipara Greensand , Waipara River, Canterbury, New Zealand; from site S2; found on 24.9.2022 by L. Love; late Early to earliest Middle Paleocene (Danian or Selandian), NZDP5 (about 62.4–61.4 Mya) .

Tentatively referred specimen: UC 22082 ( Fig. 14P; right tibiotarsus).

Locality and horizon: UC 22082 : Waipara Greensand , Waipara River, Canterbury, New Zealand; from site S2; found on 26.11.2022 by L. Love; earliest Middle Paleocene (Selandian) , NZDP6 (about 61.4–59.5 Mya) .

Measurements (in mm): See Table 1 for humerus, ulna, and tibiotarsus lengths. Additional measurements: UC 22081: humerus, distal end, 16.4; proximal end, 21.4. UC 22082: tibiotarsus, distal end, 15.5.

Remarks: The holotype is from the oldest sections of the Waipara Greensand. The tibiotarsus is referred to D. primaevus based on size, with the ratio of humerus length (UC 22081) to tibiotarsus length (UC 22082) being 0.76 (0.70 in the Muriwaimanu tuatahi specimen UC 22078).

With a length of about 43.4 mm, an exceptionally short and worn ulna ( Fig. 12J; UC 22083), which stems from site S1 and lacks exact stratigraphic data, appears to be too short to belong to D. primaevus . For this specimen and the holotype, the ratio of humerus length (UC 22081) to ulna length (UC 22083) is 1.84, whereas it is 1.44 in M. tuatahi (UC 22078), 1.53 in Kupoupou stilwelli (NMNZ S.47308), and 1.40–1.44 in Sequiwaimanu rosieae (CM 2016.6.1).

cf. Kupoupou Blokland et al., 2019