Chatham Island Paleocene fossils provide insight into the palaeobiology, evolution, and diversity of early penguins (Aves, Sphenisciformes).
CT SCANNED SPECIMENS
The positioning of bones encased within the hard lithological blocks that were CT scanned (see Materials and Methods), NMNZ S.47302 and S.47303, are indicated in Figure A1 and Figure A2 respectively. CT scanning and manipulation using Materialise Mimics also permitted insight into the cross-section of long bones in NMNZ S.47303 (Figure A3).
LINKING OF SPECIMENS
All specimens of Kupoupou stilwelli n. gen. et sp. were linked through overlapping skeletal elements (Figure A4), as well as both being found in the “bird horizon” of the Takatika Grit rock unit, and same general locality. These specimens also all share a similar size range, with intraspecific variation taken into account.
Elements that could not be confidently identified are indicated in Figure A1 and Figure A2. Various elements were also considered too incomplete and/or too uninformative to be formally described in the main text. These elements, consisting of ribs and vertebrae, are displayed in Figure A5.
GenBank molecular sequences
Molecular data (Table A1) were used as per the corrected dataset of Ksepka et al. (2012), available from Dryad (http:datadryad.org). See Ksepka et al. (2012) for references related to GenBank accession numbers. Genetic data for Phaethon rubricauda was added: AF158251, Stanley and Harrison (1999).
Parsimony analysis of larger Chatham Island specimens as separate taxa
Both NMNZ S.47302 and NMNZ S.47304 were treated as separate taxa in preliminary phylogenetic analyses to test whether they were compatible to be combined in further analyses. Except for this taxonomic modification, parsimony-based analysis using the same specifications as the primary search strategy produced 13,600 MPTs, L = 5,245 steps, CI = 0.5239, RI = 0.7015, HI = 0.4761. After pruning of taxa as per the primary analysis 9,586 non-duplicate MPTs were retained, L = 5,233, CI = 0.5251, RI = 0.7070, HI = 0.4749.
Following pruning, the strict consensus program recovered both of these specimens positioned on a large polytomy with several Eocene species and all Paleocene taxa except for Waimanu manneringi and Muriwaimanu tuatahi— which exist as a separate basal clade. The majority rule consensus (50%) tree (Figure A6) recovered better topological resolution, where the Waipara giant penguin is positioned one node crownwards of the Sphenisciformes base, and K. stilwelli n. gen. et sp., C. unienwillia, K. maxwelli, and a branch leading to a nested clade of S. rosieae and ?C. waiparensis are another node crownwards. NMNZ S.47304, K. biceae, and NMNZ S.47302 exist at separate nodes in succession respectively towards crown group Sphenisciformes.
While it is recognised that these two specimens were found at different topological positions in the majority-rule (50%) consensus tree, the recovery of K. biceae (and NMNZ S.47302) one node crownwards of NMNZ S.47304 was found in only 61% of MPTs, and similarly the positioning of NMNZ S.47302 a node crownwards of K. biceae occurred only in 53% of MPTs. This implies that a sizeable percentage of MPTs recovered these taxa in different topological positions. This uncertainty is illustrated in the poorly resolved strict consensus tree. Moreover, NMNZ S.47302 was found to have extremely high levels of taxon instability among trees, compared to other fossil and extant taxa (as well as compared to when both NMNZ S.47302 and S.47304 were merged). Relatively poor representation of NMNZ S.47302, S.47304 and most fossil taxa in the phylogenetic datamatrix compared to extant counterparts also precludes a robust phylogenetic hypothesis for stem relationships (though may be more beneficial than not having a hypothesis at all, see Wiens and Reeder, 1995; Wiens, 2003).
With the information at-hand, considering that these specimens were recovered at the same node in the strict consensus tree, we interpret these specimens as compatible to include as a single merged taxon for final analyses (larger Chatham Island form). Their merging is also supported by their recovery in the same approximate location, from the same horizon of the Takatika Grit on Chatham Island, as well as their comparable size. It should be noted, however, that without overlapping skeletal elements between specimens they cannot be considered as the same taxon with certainty.
Parsimony analyses excluding referred specimens of Seymour Island taxa
A preliminary analysis excluding scorings relating to all specimens referred to Seymour Island taxa was also performed. Removed codings pertained to the following taxa, which were effectively only represented by holotype specimens in the phylogenetic data matrix: Marambiornis exilis, Mesetaornis polaris, Palaeeudyptes klekowskii, Palaeeudyptes gunnari, Anthropornis sp. UCMP 321023, Anthropornis nordenskjoeldi, Anthropornis grandis, Notodyptes wimani, Delphinornis gracilis, Delphinornis arctowskii, and Delphinornis larseni. Testing the exclusion of these taxa was considered necessary due to the phylogenetic uncertainty many of these taxa create, in having been named on single elements, and additional bones uncertainly referred (see Jadwiszczak, 2006a; Jadwiszczak, 2006b; Ksepka and Clarke, 2010), to assess whether the removal of referred elements had a profound effect on topology and support values.
Parsimony-based analysis was conducted using the same specifications as the primary search strategy, with the exception of additionally excluded taxa. This produced 400 MPTs (L = 5256, RI = 0.7145, CI = 0.5240, HI = 0.4772), 340 of which were not duplicates following the pruning of further taxa (as per primary analysis), L = 5,212, RI = 0.7014, CI = 0.5272, HI = 0.4728. The strict consensus tree recovered W. manneringi and M. tuatahi as sister taxa that branch from the base of Sphenisciformes. The Waipara giant penguin is positioned one node crownwards of the sphenisciforms base in all MPTs. All other Paleocene taxa and Eocene taxa such as Mesetaornis, Delphinornis and Marambiornis exist in an unresolved polytomy one node crownwards of the Waipara giant penguin in the strict consensus tree. The majority-rule (50%) consensus tree provides better resolution to this polytomy (Figure A7), where in 63% of MPTs C. unienwillia, ?C. waiparensis, and S. rosieae form a clade that branches from this node, where the latter two have a sister taxon relationship. K. stilwelli n. gen. et sp. is recovered one node crownwards of this node, in 63% of MPTs. In 69% of MPTs, crownwards of this node, the larger Chatham Island form, K. maxwelli, Delphinornis arctowskii and Delphinornis larseni occupy an unresolved polytomy with a nested clade consisting of Delphinornis gracilis, Mesetaornis polaris and Marambiornis exilis in 51% of shortest trees. K. biceae is positioned one node crownwards of this polytomy in 69% of MPTs.
In most MPTs exclusion of material referred to Seymour Island taxa revealed some novel pairings of taxa compared to the primary search strategy (Figure 13). The late early-middle Paleocene larger Chatham Island form was recovered alongside Eocene forms, and late Paleocene K. biceae was recovered crownwards of some Eocene sphenisciforms, which, while not implausible, would imply an evolutionary scenario where Delphinornis, Marambiornis, Kaiika, and Mesetaornis exist on long branches. However, since this relationship was not found in a supermajority of trees, and is not supported by high bootstrap values, this topology cannot be treated with confidence. More material associated with each taxon is needed to inform more completely on the skeleton of each of these early penguins, in order to substantiate relational assessments. While the Seymour Island taxa often lack definitive material compared to each taxon, we opt to include material that has been referred, to more completely sample the skeletons of these taxa as is currently understood, to better represent them in the data matrix and test them phylogenetically among other penguins. Additionally, considering the exclusion of Eocene Seymour Island penguins did not considerably improve topological resolution, nor bootstrap support values, the exclusion of material referred to Seymour Island taxa was not deemed appropriate.
Final parsimony analysis
The strict consensus tree of the 16,300 MPTs (length = 5,234) is shown in Figure A8. Of these MPTs, 6,590 different topological variations of the shortest tree were retained following pruning, a sample of which, relating to Paleocene taxa, are shown in Figure A9.
Ages for taxa
The majority of ages for taxa as illustrated in Figure 13 are based on those given in Gavryushkina et al. (2017). Ages for taxa that were not included in Gavryushkina et al. (2017) are given here:
Anthropodyptes gilli —17.6-21.0. Park and Fitzgerald (2012) list this taxon as early Miocene in age between 17.6 and 21.0 million years ago.
Anthropornis sp. UCMP 321023—34-52.5 Ma. This fossil, which represents an unique Anthropornis species that has not been formally named, comes from the La Meseta Formation, Seymour Island, Antarctica (Ksepka, 2007). It is given the same age range as both A. nordenskjoeldi and A. grandis.
Arthrodytes andrewsi —23.8-25.9 Ma. Bajo de San Julián (Acosta Hospitaleche and Tambussi, 2008), or lower “Patagonian Formation” (Simpson, 1972), Santa Cruz Province, Patagonia, South America, a conservative age range spans both the lower Gran Bajo Member and the upper Meseta Chica Member, and is constrained between 23.83 and 25.93 Ma after Parras et al. (2008).
Crossvallia unienwillia— 56-59.2 Ma. The holotype was recovered from the Cross Valley C Allomember, and is cited as Thanetian in age in Jadwiszczak et al. (2013).
?Crossvallia waiparensis— 59-61.5 Ma. This taxon was described from fossils from site S2, of the Mt. Ellen Member concretionary member (as indicated in Mayr et al., 2018), of the Waipara Greensand, Waipara River, Canterbury, New Zealand (Mayr et al., 2019). It is therefore considered to be of within the same age range as Sequiwaimanu rosieae, the holotype of which was also recovered from this site (see below).
Eudyptes calauina —2.58-5.3 Ma. From the Horcon Formation, Chile, attributed to Late Pliocene in age Chávez Hoffmeister et al. (2014). We conservatively bound the age of this taxon from the base of the Pliocene to the latest Pliocene.
Hakataramea penguin—21.7-25.2 Ma. From Hakataramea Valley, New Zealand, material associated with this taxon was recovered from the Otekaike Limestone, and is Waitakian in age (Ando, 2007).
Inguza predemersus— 2.58-5.25 Ma. Associated with Langebaanweg, Cape Province, South Africa, the holotype is associated with the Muishond Fontein Phosphatic Sand Member of the Varswater Formation (Simpson, 1971a; Ksepka and Thomas, 2012), where fossils are inferred to be 5.15 ± 0.1 Ma (Roberts et al., 2011). This taxon is therefore conservatively bounded between the earliest Pliocene and the overlying Pleistocene Langebaan Formation (Roberts et al., 2011).
Kaiika maxwelli —50-63 Ma. The holotype and only known specimen was recovered in a concretion from the southern bank of the Waihao River, South Canterbury, New Zealand. The age of the specimen is uncertain, and may have originated from the Kauru Formation, as discussed in Fordyce and Thomas (2011). While the age of the Kauru Formation at the source location is problematic, the age is cited as Waipawan or Mangaorapan, but molluscs in the lower Waihao Kauru Formation characteristic of the Wangaloan Stage increases the possible age range into the Paleocene (Fordyce and Thomas, 2011). Thus, we have opted for a conservative age estimate bounded between the uppermost Mangaorapan (50 Ma) and the middle Teurian (63 Ma).
Kumimanu biceae —55.5-59.5 Ma. Mayr et al. (2017b) note that the holotype is associated with the Moeraki Formation, and is dated to the late Teurian between 55.5 and 59.5 Ma.
Nucleornis insolitus —2.58-5.25 Ma. Discovered at Koeberg Nuclear Power Station, Cape Province, South Africa, the holotype is associated with the Muishond Fontein Phosphatic Sand Member of the Varswater Formation (Simpson, 1979; Ksepka and Thomas, 2012), where fossils are inferred to be 5.15 ± 0.1 Ma (Roberts et al., 2011). This taxon is therefore conservatively bounded between the earliest Pliocene and the overlying Pleistocene Langebaan Formation (Roberts et al., 2011).
Palaeeudyptes marplesi —34.6-39.1 Ma. Material attributed to this species were recovered from the Burnside Mudstone, Kaiatan or Runangan in age (Simpson, 1971b). Based on Raine et al. (2015) this constrains the taxon’s age between 34.6 and 39.1 Ma.
Paraptenodytes antarcticus —17.9-22.1 Ma. We revised the possible age range of P. antarcticus from what was used in Gavryushkina et al. (2017) based on 87Sr/86Sr dates of the Monte León Formation, between 17.91 Ma at the top of the Formation, and 22.12 Ma as an older limit (Parras et al., 2012).
Paraptenodytes brodkorbi —23.8-25.9 Ma. From the San Julián Formation or lower “Patagonian Formation”, Patagonia, South America (Simpson, 1972; Ksepka and Ando, 2011), a conservative age range spans both the lower Gran Bajo Member and the upper Meseta Chica Member, and is constrained between 23.83 and 25.93 Ma after Parras et al. (2008).
Paraptenodytes robustus —23.8-25.9 Ma. From the San Julián Formation or lower “Patagonian Formation”, Patagonia, South America (Simpson, 1972; Ksepka and Ando, 2011), a conservative age range spans both the lower Gran Bajo Member and the upper Meseta Chica Member, and is constrained between 23.83 and 25.93 Ma after Parras et al. (2008). Material attributed to this taxon from Bahía Inglesa, Chile were shown to be unreliable by Chávez (2007).
Platydyptes amiesi —21.7-27.3 Ma. The holotype is Waitakian of the Hakataramea Valley, New Zealand (Marples, 1952), and material referred to this taxon may also be associated with the Duntroonian Stage (Simpson, 1971b). Based on the dates given in (Raine et al., 2015), this taxon is therefore constrained between the base of the Duntroonian as an older age limit (27.3 Ma), and the base of the Otaian Stage as the younger age limit (21.7 Ma).
Pseudaptenodytes macraei —5.0-6.0 Ma. Park and Fitzgerald (2012) list this taxon as ranging from the late Miocene (6 Ma) to early Pliocene (5 Ma).
SAM P7158 cf. Palaeeudyptes —36.5-38 Ma. In a review of Australian fossil penguins Park and Fitzgerald (2012) list SAM P7158 as Late Eocene in age between 36.5 and 38 Ma.
Sequiwaimanu rosieae —59-61.5 Ma. Recovered from the Waipara Greensand near the position of where the holotype of Waimanu manneringi was discovered, this material is dated to the early late Teurian (Mayr et al., 2018), about 61 Ma. A conservative age range to conform to early late Teurian dates based on Raine et al. (2015) potentially constrains the fossils between the base age of the upper Teurian of 61.5 Ma and a lower limit of 59 Ma.
Sphenisciformes indet. NMV P221273—7.25-7.92 Ma. This specimen was recovered from the lower light grey unit of the Port Campbell Limestone, Portland Bay, Victoria, Australia, and is described as Tortonian in age (Park et al., 2016).
Sphenisciformes indet. SAM P10863—23-30 Ma. The partial right humerus of SAM P10863 was recovered from the Gambier Limestone, Mt Gambier, South Australia, and is given an age of ~23-30 Ma in a review of Australian fossil penguins (Park and Fitzgerald, 2012).
Waipara Greensand giant penguin CM 2016.158.1—59-61.5 Ma. This specimen was recovered from the Waipara Greensand 11 m above those where the holotype of Waimanu manneringi was discovered, and is dated to the early late Teurian (Mayr et al., 2017a), about 61 Ma. A conservative age range to conform to early late Teurian dates based on Raine et al. (2015) potentially constrains the fossils between the base age of the upper Teurian of 61.5 Ma and a lower limit of 59 Ma.
Specimens examined for each referred species, and any coding changes for characters are listed in Table A2. Note that for species that were newly coded in full, such as Phaethon rubricauda, Kupoupou stilwelli n. gen. et sp., the Large Chatham Island form, and ?Crossvallia waiparensis, coding of these taxa is available in the NEXUS file of the Chatham matrix.
Inconsistencies exist in the literature regarding how specific features of the hypotarsus are labelled, on the proximal tarsometatarsus, in Sphenisciformes. Building on the work of Jadwiszczak (2015), we have labelled structures of hypotarsus of various sphenisciforms to conform with the terminology specified in Mayr (2016), as shown in Figure A10.
MORPHOLOGICAL CHARACTER DEFINITIONS AND STATES
Citations corresponding to where each character definition originated is indicated by the following abbreviations: New characters or those that have been modified in this study are also indicated. A, Ando (2007); AH, Acosta Hospitaleche et al. (2007); BG, Bertelli and Giannini (2005); C, Clarke et al. (2007); CHa, Chávez Hoffmeister et al. (2014); CHb, Chávez Hoffmeister (2014b); CL, Clarke et al. (2010); D, Degrange et al. (2018); GB, Giannini and Bertilli (2004); K, Ksepka et al. (2006); KC, Ksepka and Clarke (2010); KT, Ksepka and Thomas (2012); KF, Ksepka et al. (2012); LZ, Livezey and Zusi (2007); M, Mayr et al. (2017b); OH, O'Hara (1989).
1. Tip of mandibular rhamphotheca, profile in lateral view: pointed (0); slightly truncated (1); strongly truncated, squared off (2); truncated but with a rounded margin (procellariiform-like) (3). (GB1)
2. Longitudinal grooves on base of culmen: absent (0); present (1). (GB2)
3. Longitudinal grooves on base of latericorn and ramicorn: absent (0); present (1). (GB3)
4. Feathering of maxilla: totally unfeathered (0); slightly feathered, less than half the length of maxilla feathering that reaches half the length of maxilla. (GB4) Ordered.
5. Ramicorn, inner groove at tip: absent (0); present and single (1); present and double (2). (GB5) Ordered.
6. Orange or pink plate on ramicorn: absent (0); present (1). (GB6)
7. Plates of rhamphotheca, inflated aspect: absent (0); present (1). (GB7)
8. Gape: not fleshy margin (0); narrowly fleshy margin (1); markedly fleshy (2). (GB8) Ordered.
9. Ramicorn primary colour pattern: black (0); red (1); pink (2); yellow (3); orange (4); green (5); blue (6); black rostrally but pinkish-orange caudally (7). (GB9)
10. Latericorn, ramicorn, and premaxillary nail, light distal mark: absent (0); present (1). (GB10)
11. Latericorn colour: black (0); dark red and black (1); orange (2); yellow (3); green (4); blue (5). (GB11)
12. Culminicorn: black (0); reddish orange (1); pale orange (2). (GB12)
13. Maxillary and mandibulary unguis, color: black (0); reddish orange (1); yellow (2); green (3); blue-grey (4). (GB13)
14. Ramicorn, ultraviolet reflectance peak (corresponds to the orange spot): absent (0); present (1). (KC14)
15. Bill of downy chick, colour: dark (0); reddish (1); pale, variably horn to yellow (2); subtle dark reddish markings at base (3); bluish (4). (GB14)
16. Bill of immature, colour: dark (0); bicoloured red and black (1); red (2); yellow (3); grey (4). (GB15)
17. External nares: present (0); absent (1). (GB17)
18. Nostril tubes in adult: absent (0); present (1). (GB16)
19. Nostril tubes in hatchling: absent (0); present (1). (GB16)
20. External nares: well-separated (0); fused at midline (1). (KC19)
21. Iris colour: brown (0); silvery grey (1); claret red (2); yellow (3); white (4). (GB18)
22. Scale-like feathers: absent (0); present (1). (GB19)
23. Rachis of contour feathers: cylindrical (0); flat and broad (1). (GB20)
24. Rectrices: form a functional fan (0); do not form a fan (1). (GB21)
25. Remiges: differentiated from contour feathers (0); indistinct from contour feathers (1). (GB22)
26. Apteria: present (0); absent (1). (GB23)
27. Molt of contour feathers: gradual (0); simultaneous (1). (GB24)
28. Yellow pigmentation in crown feathers (pileum): absent (0); present (1). (GB25)
29. Head plumes (cristea pennae): absent (0) present (1). (GB26)
30. Head plumes: compact (0); sparse (1). (GB27)
31. Head plumes: directed dorsally (0); directed posteriorly, not drooping (1); directed posteriorly, drooping (2). (GB28)
32. Head plumes, position of origin: at base of bill close to gape (0); on the recess between latericorn and culminicorn (1); on forehead (2). (GB29) Ordered.
33. Head plumes, colour: yellow (0); orange (1). (GB30)
34. Nape (occiput), crest development: absent (0); slight (1); distinct (2). (GB31) Ordered.
35. Periocular region: black (0); white (1); yellow (2) bluish grey (3). (GB32)
36. Fleshy eyering: absent (0); present (1). (GB33)
37. White eyering: absent (0); present (1). (GB34)
38. White eyebrow (supercilium): absent (0); narrow, from postocular area (1); narrow, from preocular area (2); wide, from preocular area (3). (GB35) Ordered.
39. Loreal area (lorum): feathered (0); patch of bare skin extending from eye to base of culminicorn (1); patch of bare skin extends from eye to gape, with narrow patch of bare skin at margin of lower beak (2); patch of bare skin extends from eye to gape, with extensive patch of bare skin at margin of lower beak (3). (GB36) Ordered.
40. Auricular patch (regio auricularis): absent (0); present (1). (GB37)
41. Throat pattern: black (0); white (1); yellow (2); irregularly streaked (3); with chinstrap (4). (GB38)
42. Collar: absent (0); at most slight notch present (1); present, diffusely demarked (2); black, strongly demarked (2). (GB39) Ordered.
43. Breast, golden colour: absent (0); present (1). (GB40)
44. Dorsum: black (0); dark bluish grey (1); light bluish grey (2). (GB41)
45. Black marginal edge of dorsum between lateral collar and axillary patch, contrasting with dorsum: absent (0); present (1). (GB42)
46. Black dots irregularly distributed over white belly: absent (0) present (1). (GB43)
47. Flanks, dark lateral band reaching the breast: absent (0); present (1). (GB44)
48. Distinct dark axillary patch of triangular shape: absent (0); present (1). (GB45)
49. Flanks, extent of dorsal dark cover into the leg: incomplete, not reaching tarsus (0); complete, reaching tarsus (1). (GB46)
50. Rump, colour: indistinct in colour from dorsum (0); distinct white patch (1). (GB47)
51. Tail length: short, the quills barely emerge from the rump (0); quills distinctly developed (1). (GB48)
52. Outer rectrices, colour: same colour as inner rectrices (0); lighter than inner rectrices (1). (GB49)
53. White line connecting leading edge of flipper with white belly: absent (0); present (1). (GB50)
54. Flipper, upperside, light notch at base: absent (0); present (1). (GB51)
55. Leading edge of flipper, pattern of upperside: black (0); white (1). (GB52)
56. Leading edge of flipper, pattern of underside: white (0); incompletely dark (1); completely dark and wide (2). (GB53)
57. Flipper, underside, dark elbow patch: absent (0); present (1). (GB54)
58. Flipper, underside, tip pattern: immaculate (0); patchy, in variable extent (1); small circular dot present (2). (GB55)
59. Immature plumage, white eyebrow (supercilium): absent (0); present (1). (GB56)
60. Immature plumage, throat pattern (jugulum): black (0); mottled (1); white (2); brown (3). (GB57)
61. Immature plumage, flanks, dark lateral band: absent (0); present (1). (GB58)
62. Chicks hatch almost naked: no (0); yes (1). (GB59)
63. Dominant colour pattern of first down: pale grey (0); distinctly brown (1); bicoloured, dark above and whitish below (2); uniformly blackish grey (3). (GB60)
64. Dominant colour pattern of second down: pale grey (0); distinctly brown (1); bicoloured, dark above and whitish below (2); uniformly blackish grey (3). (GB61)
65. Chick, second down, collar: absent (0); present (1). (GB62)
66. Feet, dorsal colour: dark (0); pink (1); orange (2); white-flesh (3); blue (4). (GB63)
67. Feet, soles distinctly darker than dorsal surface: absent (0); present (1). (GB64)
68. Feet, unguis digiti: flat (0); compressed (1). (BG65)
69. Clutch size: two eggs (0); one egg (1). (GB65)
70. Incubatory sac: absent (0); present (1); (GB66)
71. Nest: no nest, incubation over the feet (0); nest placed underground, either burrowed in sand or inside natural hollow or crack (1); open nest, a shallow depression on bare ground or in midst of vegetation (3). (GB67)
72. Size of first egg relative to the second egg: similar (0); first egg smaller (1); first egg larger (2). (GB68)
73. Crèche: absent (0); small, 3-6 birds (1); formed by dozens to hundreds of immatures (2). (GB69)
74. Egg shape: oval (0); conical (1); spherical (2). (BG71)
75. Ecstatic display: absent (0); present (1). (BG72)
76. Premaxilla, tip (rostrum maxillare): pointed (0); weakly hooked (1); strongly hooked (2). (GB0) Ordered.
77. Internarial bar (pila supranasalis) shape in cross section: sub-oval (0); inverted U-shape (1). (C75)
78. Internarial bar (pila supranasalis), width: wide throughout its length (0); slender, slightly constricted laterally (1). (OH6)
79. Internarial bar (pila supranasalis), profile in lateral view: dorsal edge curves smoothly to tip of beak (0); pronounced step in dorsal edge (1). (KC78)
80. Nasal cavity, external naris (cavum nasi, apertura nasi ossea), caudal margin: extended caudal to the rostral margin of the hiatus orbitonasalis (0); not extended caudal to the rostral margin of the hiatus orbitonasalis (1). (OH5)
81. Premaxilla, frontal process, naso-premaxillary suture: visible (0); obliterated (1). (BG95)
82. Basioccipital, subcondylar fossa (fossa subcondylaris): absent or shallow (0); deep (1). (BG73)
83. Supraoccipital, paired grooves for the exit of v. occipitalis externae (sulcus vena occipitalis externae): poorly developed (0); deeply excavated (1). (BG74)
84. Frontal, shelf of bone bounding salt-gland fossa (fossa glandulae nasalis) laterally: absent (0); present (1). (OH10)
85. Squamosal, temporal fossa (fossa temporalis), size: fossae separated by considerable wide surface (at least the width of the cerebellar prominence (0); more extensive, fossae meeting or nearly meeting at midline of the skull (1). (BG76)
86. Squamosal, temporal fossa (fossa temporalis), depth of caudal region: flat (0); shallow (1); greatly deepened (2). (BG77) Ordered.
87. Squamosal, development of the opening that transmits the a. ophthalmica externa in the caudoventral area of the temporal fossa (near nuchal crest): small or vestigial (0); well-developed (1). (BG78)
88. Orbit, fonticuli orbitocraniales: small or vestigial (0); broad and conspicuous openings (1). (BG79)
89. Ectethmoid: absent (0); weakly developed, widely separate from the lacrimal (1); well developed, contacting or fused to the lacrimal (2). (BG80)
90. Lacrimal, descending process: unperforated (0); perforated (1). (OH11)
91. Lacrimal, pneumatic foramen: absent (0); present by large lacrimal foramen. (D90)
92. Lacrimal: reduced, concealed in dorsal view (0); small portion exposed in dorsal view (1); well-exposed in dorsal view (2). (BG82) Ordered.
93. Lacrimal, contact with frontal: suture (0); fusion (1). (KT89)
94. Lacrimal, dorsal process: closely applied to the nasal (0); rostral arm of dorsal process separated from the nasal by a slit-like rostro-caudally elongate opening (1). (BG83)
95. Basitemporal plate (lamina parasphenoidalis), dorsoventral position with respect to the occipital condyle: ventral to the level of the condyle (0); at the level of the condyle (1); dorsal to the level of the condyle, surface depressed (2). (BG86) Ordered.
96. Basipterygoid process (processus basipterygoideus): absent (0); vestigial or poorly developed (1); well-developed (2). (BG87) Ordered.
97. Eustachian tubes (tuba auditiva): open or very little bony covering near the caudal end of the tube (0); mostly enclosed by bone (1). (BG88)
98. Pterygoid, shape: elongated (0); slight lateral expansion of rostral end (1); rostral end broad, pterygoid sub-triangular (2). (BG89) Ordered.
99. Palatine, lamella choanalis: curved and smooth plate, slightly differentiated from main palatine blade (0); ridged, distinct from main blade by a low keel (1); extended vertically ventrally forming the crista ventralis (2). (BG90) Ordered.
100. Vomer: laterally compressed, vertical laminae and free from palatines (0); horizontally flattened laminae and ankylosed with palatines (1). (BG91)
101. Facial foramen (foramen n. facialis) (ossa otica, fossa acustica interna): absent (2); present (1). (BG92)
102. Jugal arch, bar shape in lateral view: straight (0); slightly curved (1); ventrally bowed (2); strongly curved, sigmoid shape (3). (BG93) Ordered.
103. Jugal arch, dorsal process (this pointed process is located on the caudal end of the jugal, adjacent to the condyle for articulation with the quadrate: absent (0); present (1). (BG94)
104. Quadrate, relative lengths of otic and orbital processes (processus oticus and processus orbitalis): orbital process longer (0); otic process longer (1). (KC102)
105. Quadrate, otic process (processus oticus), rostral border, tubercle for m. adductor mandibulae externus, pars profunda: absent (0); present, as a ridge (1); present, as a tubercle (2). (BG96) Ordered.
106. Quadrate, otic process (processus oticus), rostral border, tubercle for m. adductor mandibulae externus, pars profunda: contiguous with squamosal capitulum (0); separated from squamosal capitulum (1). (KC104)
107. Quadrate, processus oticus, caudal margin in lateral view: straight (0); flexed so as to be concave caudally (1). (A9)
108. Tomial edge (crista tomialis): plane of tomial edge approximately at the level of the basitemporal plate (lamina parasphenoidalis) (0); dorsal to the level of the basitemporal plate (1). (BG97)
109. Mandible, symphysis: extensive bony connection (0); short terminal bony connection (1). (C101)
110. Mandible, posteriorly projected midline spur from dentary underlying symphysis: absent (0); present (1). (KC107)
111. Mandible, rostral fenestra (fenestra mandibulae rostralis): imperforate or small opening (0); large opening (1). (OH8)
112. Mandible, caudal fenestra (fenestra mandibulae caudalis): open, can be seen through from the medial or lateral aspects (0); nearly or completely concealed by the splenial medially (i.e., fenestra not visible in the medial aspect) (1). (OH9)
113. Mandible, mandibular ramus: depth subequal over entire ramus (0); pronounced deepening at midpoint (1). (BG101)
114. Mandible, mandibular ramus: essentially straight or gently sloping (0); pronounced ventral deflection near midpoint (1). (KC112)
115. Mandible, dentary, length of dorsal edge relative to mandibular ramus length in lateral view: markedly more than half the length of ramus (0); approximately half the length of ramus (1). (BG103)
116. Mandible, articular, medial process (processus medialis): not hooked (0); hooked (1). (BG104)
117. Mandible, angular, aspect in dorsal view: sharply truncated caudally projected, forming retroarticular process (processus retroarticularis). (BG106)
118. Mandible, angular, retroarticular process (processus retroarticularis), aspect in dorsal view in relation to the articular area for the quadrate between the lateral and medial condyles (condylus lateralis and condylus medialis): broad, approximately equal to the articular area (0); moderately long, narrower than the articular area (1); very long, longer and narrower than the articular area (2). (BG105) Ordered.
119. Mandible, medial emargination between medial and retroarticular processes (processus retroarticularis and processus medialis): absent (0); weak (1); concavity (2); strong concavity (3). (K108) Ordered.
120. Mandible, coronoid process (processus coronoideus), position on the dorsal margin of the mandible with respect to caudal mandibular fenestra (fenestra mandibulae caudalis): markedly rostral (0); on the rostral end of the fenestra (1) caudal to fenestra (2). (BG98)
121. Atlas, processus ventralis: absent or slightly developed (0); well developed, high and prominent ridge on the ventral surface of the arcus atlantis (1). (BG108)
122. Transition to free cervicothoracic ribs: starting at 13th cervical vertebra (0); starting at 14th cervical vertebra (1); starting at 15th cervical vertebra (2). (BG109) Ordered.
123. Cervical vertebrae, transverse process (processus transversus) in last five cervical vertebrae: not elongated laterally (0); greatly elongated laterally (1). (BG111)
124. Thoracic vertebrae, posterior-most vertebrae: heterocoelous (0); weakly opisthocoelous (1); strongly opisthocoelous (2). (K114) Ordered.
125. Thoracic vertebrae, deep excavation on lateral face of posterior thoracic vertebrae: absent (0); present (1). (KC124)
126. Synsacrum, number of incorporated vertebrae: nine (0); eleven (1); twelve (2); thirteen (3); fourteen (4); fifteen or more (5). (C117)
127. Synsacrum, height of crista synsacri between acetabula: flat or weakly projected (0); strongly projected (1). (KC126)
128. Synsacrum, first incorporated vertebra, position of fovea costalis: caudal to level of processus transversus (0); cranial to level of transverse process (1). (KF230)
129. Synsacrum, ventral surface of first few incorporated vertebrae: rounded or flattened (0); sharp, blade-like ventral margin (1). (A63)
130. Caudal vertebrae: seven (0); eight (1); nine or more (2). (BG113) Ordered.
131. Pygostyle, shape: tapers to a narrow edge both dorsally and ventrally as in most volant birds (0); triangular in cross-section with a wide, flat ventral margin (1). (KF232)
132. Thoracic ribs, uncinate processes (costae, processes uncinati): elongate, narrow (0); wide at base, spatulate (1); extremely wide at base (2). (BG114)
133. Thoracic ribs, uncinate processes (costae, processes uncinati): fused to ribs (0); unfused (1). (KC129)
134. Sternum, external spine (spina externa rostri): absent (0); present (1). (OH13)
135. Sternum, facies articularis furculae projects as a distinctive process: absent (0); present (1). (BG116)
136. Sternum, orientation of sulcus articularis coracoideus in ventral view: sulci oriented in essentially straight horizontal line (0); sulci directed caudolaterally so as to together form an inverted U shape (1). (A15)
137. Sternum, articular facets for coracoids (sulcus articularis coracoideus): meet or overlap one another at midline (0); separated by wide non-articulatory surface (1). (C122)
138. Sternum, labrum internum: continues as sharp ridge onto the base of the spina externa (0); fades away without continuing onto the base (1). (C123)
139. Sternum, caudal incisurae. none (0); two (1); four (2). (KC134)
140. Sternum, trabecula lateralis projects caudal to main body of sternum: no (0); yes (1). (KF234)
141. Furcula, hypocleidium (apophysis furculae): absent or low knob-like process (0); long, blade-like process (1). (BG117)
142. Furcula, ramus: sub-ovoid in cross-section at omal end (0); mediolaterally flattened and craniocaudally expanded at omal end (1). (CL218)
143. Scapula, acromion: craniodorsally directed, nearly parallel to long axis of scapular shaft at apex (0); forms a blunt triangular projection with apex directed approximately at 45 degree angle from long axis of scapular shaft (1); narrow and tapering, apex omally directed (2); narrow and tapering, apex directed at a right angle to scapular shaft (3). (CL223) Ordered.
144. Scapula, blade, caudal half (corpus scapulae, extremitas caudalis: blade-like (0); slightly expanded (1); broadly expanded, paddle-shaped (2). (BG118) Ordered.
145. Scapula, facies articularis humeralis: rounded, projecting from shaft of scapula (0); compressed and ovoid, projecting from shaft of scapula (1); flattened and nearly merged with shaft of scapula (2). (KF235)
146. Coracoid, length: shorter than humerus (0); greatly elongated, longer than humerus (1). (KC137)
147. Coracoid, scapular cotyle (scapula cotylaris) deep and socket-like (0); moderately concave (1); nearly flat (2). (CL217)
148. Coracoid, processus acrocoracoideus, region of tuberculum brachiale: craniocaudally compressed (0); craniocaudally expanded, with a large flat surface cranial to tuberculum brachiale (1). (A22)
149. Coracoid, medial margin, coracoidal fenestra: complete (0); incomplete (1) absent (2). (OH14)
150. Coracoid, foramen nervi supracoracoidei, Mayr (2005) cited ontogenetic evidence that this foramen is not homologous to the coracoidal fenestra of penguins: absent (0); present (1). (K122)
151. Coracoid, sternal margin (extremitas sternalis coracoidei): greatly expanded (0); moderate expansion (1). (BG120)
152. Coracoid, profile of the sternal margin (extremitas sternalis coracoidei) in ventral view: convex (0); concave (1); flat (2). (K124)
153. Coracoid, facies articularis sternalis, dorsal surface: single facet (0); two facets (1). (KF236)
154. Coracoid, lateral process (processus lateralis): absent or highly reduced (0); well-developed (1). (KC142)
155. Forelimb elements: sub-circular in cross section (0); strongly dorsoventrally compressed (1). (BG121)
156. Humerus, head, very developed and reniform, continuous with tuberculum dorsale: moderate (0); enlarged and elliptical (1); very enlarged, hemispherical to reniform (2). (BG122) Ordered.
157. Humerus, head, proximal view, respect to the cranio-caudal axis: at midline (0); dorsocaudal (1); caudal (2). (CHb3) Ordered.
158. Humerus, head, dorsal (posterior) view proximal edge shape: semicircular, apex of humeral head located near midline (0); asymmetric arch with caudal apex, slightly prominent (1); asymmetric arch with caudal apex, strongly prominent (2). (C132)
159. Humerus, head, dorsal (posterior) view, notch between head and dorsal tubercle: present (0); absent (1). (CHa157)
160. Humerus, pit for ligament insertion on proximal surface adjacent to head: absent or very shallow (0); deep (1). (K128)
161. Humerus, dorsal tubercle, insertion of minor deltoid muscle, groove on proximal dorsal surface distocaudally from dorsal tubercle towards the base of the humerus head: present, deep dorsoproximal groove (0); inconspicuous to absent (1). (CHb7) Modified: Wording in definition changed for clarification.
162. Humerus, capital groove, position: caudal (0); ventrocaudal (1); ventral (2). (CHb8) Ordered.
163. Humerus, incisura capitis (capital groove), connection with sulcus transversus (transverse groove): essentially confluent with sulcus transversus, forming a single (0); connected through a narrow groove (1); completely separated (2). (K127)
164. Humerus, secondary tricipital fossa, connection with the capital incisure (capital groove): continuous, both structures are undifferentiated (0); connected, both structures are distinctive (1); completely separated (2). (CL222) Ordered.
165. Humerus, humeral intumenscentia, projection from humeral shaft: ventrally projected (0); caudally projected (1); caudoventrally projected, being well exposed in cranial view (2). (K129) Ordered.
166. Humerus, tricipital fossa, proximal view, rim, proximal margin of tricipital fossa (fossa pneumotricipitalis ventralis): not exposed to slightly exposed at the caudoventral margin (0); well-exposed along the caudal margin (1). (K135)
167. Humerus, tricipital fossa, caudal view, margin: strongly concave (0); straight to slightly concave (1). (KT153)
168. Humerus, tricipital fossa (fossa tricipitalis), developed: shallow, with penetrating pneumatic foramina (0); moderate, without pneumatic foramen (1); deep, without pneumatic foramen (2). (BG123)
169. Humerus, tricipital fossa (fossa tricipitalis): single (0); bipartite (1). (BG124)
170. Humerus, ventral tubercle (tuberculum ventrale), dorsal (caudal) view, caudal projection: long, beyond the head (0); short, at level with the head (1). (CHb16)
171. Humerus, ventral tubercle, tubercle fossa: very shallow, caudal (0); deep, caudal (1); deep, caudoventral (2). (CHb17)
172. Humerus, deltoid crest, cranial coracobrachial muscle scar (impressio m. pectoralis): superficial, poorly-defined scar (0); shallow, well-defined oblong fossa (1); deep, well-defined oblong fossa (2). (BG125) Ordered.
173. Humerus, supracoracoideus muscle scar, shape (impressio insertii m. supracoracoideus): small, semicircular scar (0); strongly protruding, greatly elongated over dorsal surface (1); flat, greatly elongated over dorsal surface (2). (K133)
174. Humerus, supracoracoideus muscle scar, position: on the dorsal tubercle, at the proximal end of the humerus (0); on shaft dorsal surface, straight to slightly oblique (1); on shaft dorsal surface, strongly oblique (2). (CHb20) Ordered. Modified: Wording was changed for character state 0, for clarification.
175. Humerus, supracoracoideus and latissimus dorsi muscle scars, separation (impressio insertii m. supracoracoideus and m. latissimus dorsi): separated by a wide gap (0); separated by a moderate gap separated by small gap or confluent. (K134) Ordered.
176. Humerus, caudal coraacobrachial muscle scar (coracobrachialis caudalis scar), contact with the distal margin of head: absent (0); present (1). (CL219)
177. Humerus, caudal coracobrachial muscle attachment (coracobrachialis caudal scar): subcircular fossa (0); small tubercle (1); flattened wide ovoid scar (2); flattened narrow elongate scar (3). (CL220) Ordered.
178. Humerus, groove for coracobrachialis nerve: absent or poorly defined (0); sharp, narrow sulcus (groove) (1). (CL221)
179. Humerus, shaft, craniocaudal (dorsoventral) width: shaft thins or maintains width distally (0); shaft widens distally (1). (K136)
180. Humerus, nutrient foramen (foramen nutricum) position: situated on ventral face of shaft (0); situated on caudal face of shaft (1). (C143)
181. Humerus, shaft, ventral (anterior) view, elongate furrow along caudal margin: absent (0); present (1). (C144)
182. Humerus, shaft, ventral (anterior) view, sigmoid curvature: absent or weak (0); strong (1). (K137)
183. Humerus, shaft, shaft robustness index (proximodistal length/craniocaudal width at middle point): elongated SRI>7 (0); greatly slender, 7>SRI>6 (1); slender, 6>SRI>5 (2); thick, 5>SRI>4 (3); bulky, SRI<4 (4). (CHa176) Ordered.
184. Humerus, dorsal (posterior) view, preaxial angle: absent or inconspicuous (0); well defined (1). (CHa177)
185. Humerus, dorsal (posterior) view, caudal (ventral) edge, concavity proximal to the dorsal trochlear ridge: present (0); absent (1). (CHb31)
186. Humerus, development of dorsal supracondylar tubercle (processus supracondylar dorsalis): absent (0); vestigial, compact tubercle (1); short process (2); elongate process, well exposed in distal view (3). (BG126)
187. Humerus, dorsal (posterior) view, dorsal trochlear ridge, projection in relation with the caudal (ventral) margin of the shaft: surpassing it (0); reaching the margin (1); does not reach the margin (2). (BG128)
188. Humerus, brachial muscle scar, scar for origin of m. brachialis: cranial ovoid fossa (0); inconspicuous and elongate scar on the cranial margin, between dorsal condyle and preaxial angle (1); elongate scar on the cranial margin, with deep fossa distal to the preaxial angle (2). (A34)
189. Humerus, angle between main axis of shaft and tangent of dorsal and ventral condyles (condylus dorsalis and condylus ventralis): less than 30 degrees (0); 30 to 40 degrees (1); greater than or equal to 40 degrees (2); nearly 90 degrees (3). (K141)
190. Humerus, ulnar condyle (condylus ventralis), cranial (dorsal) and distal view: spheroidal, displaced over the ventral (anterior) edge (0); spheroidal, almost parallel to dorsal condyle (1); flattened, almost parallel to dorsal condyle (2). (K142) Ordered.
191. Humerus, distal end, humerotricipital groove: absent (0); present (1); present, delimited by troclear ridges (2). (CHb37)
192. Humerus, distal end, scapulotricipital groove (demarcation of sulcus scapulotricipitalis): not demarcated (0); well-marked groove (1); well-marked, ventrally delimited by the middle trochlea ridge (2); deep groove, delimited by the dorsal and middle trochlear ridges (3). (BG127) Ordered.
193. Humerus, distal view, scapulotricipital and humerotricipital grooves: separated (0); cranially connected (1). (CHb39)
194. Humerus, distal view, ratio ventral condyleadjacent shelf, ratio of condyle width: large, ratio <1.3 (0); moderate, 1.3\< ratio <2 (1); greatly reduced, ratio >2 (2). (K143) Ordered.
195. Humerus, ratio of width of proximal end of humerus to width of shaft. 2.4 or more (0); <2.4 (1). (M247)
196. Radius, shaft: sub-cylindrical (0); broad and flattened (1). (KC166)
197. Radius, proximally projecting spike-like process at cranial margin: absent (0); present (1). (KF239)
198. Ulna, olecranon position: arises at level of or proximally surpassing humeral cotylae (0); slightly displaced from cotylae (1); located one fourth of length to proximal end (2). (K144) Ordered.
199. Ulna, olecranon shape: short and robust tab-like projection with a rounded posterior margin (0); tab-like projection with a squared posterior margin (1); tab-like projection with a distinctive angular posterior margin (2). (CHa188) Separation of the position and shape of the olecranon into two independent characters, previously coded together in K144.
200. Ulna, incisura radialis: concave in proximal view, so that the ulna contacts the proximal radius at both its caudal and ventral surfaces (0); obsolete, so radius and ulna abut one another at a nearly flat contact (1). (KF240)
201. Ulna, presence of processus supracondylaris dorsalis (dorsal supracondylar process of ulna): present (0); absent (1). (M246)
202. Ulna, distinct process extending toward sulcus humerotricipitalis of humerus: absent (0); present (1). (K145)
203. Ulna, shaft shape: sub-cylindrical (e.g., Diomedea) (0); weak dorsoventral flattening, craniocaudally narrower distally (e.g., Sequiwaimanu) (1); strong dorsoventral flattening, prominent craniocaudal widening (e.g., Spheniscus) (2). (This study) Ordered.
204. Ulnare: U-shaped (0); triangular, fan-shaped wedge (1). (KC169)
205. Ulnare, distal angle (This character refers to the distal angle in the specialized fan-shaped ulnare of penguins and is considered non-comparable for outgroup taxa): rounded (0); pointed (1). (KF241)
206. Carpometacarpus, pisiform process (processus pisiformis): well-projected round tubercle (0); reduced to a low ridge (1). (C155)
207. Carpometacarpus, distal facet on metacarpal I: absent (0); present (1). (C156)
208. Carpometacarpus, metacarpal II, distinct anterior bowing: absent (0); present (1). (C157)
209. Carpometacarpus, extension of metacarpals II and III: subequal or III slightly shorter (0); metacarpal III projects markedly distal of metacarpal II (1). (C158)
210. Carpometacarpus, metacarpal III, distal articular surface (facies articularis digitalis major): wedge shaped or broadens anteriorly in distal view (0); slightly depressed ovoid surface (1). (C158)
211. Carpometacarpus, extensor process (processus extensorius): present (0); absent (1). (KC175)
212. Carpometacarpus, metacarpal II, distal expansion: absent (0); present (1). (KC176)
213. Phalanx III-1, proximal process: absent (0); present (1). (BG130)
214. Manual phalanges: much shorter than phalanx II-1 (0); phalanx II-1 and phalanx III-1 subequal in length (1). (C161)
215. Phalanges of manus, length relative to carpometacarpus: long (0); short (1). (BG131)
216. Fusion of ilia to synsacrum: unfused (0); partially fused (1); well fused (2). (K149) Ordered.
217. Pelvis, preacetabular ilia: flat, well-separated (0); approach one another, but do not contact at midline (1); contact at midline forming canalis iliosynsacralis (2). (KC181)
218. Pelvis, foramina intervertebralia large, forming wide openings on dorsal surface of pelvis: absent (0); present (1). (KC182)
219. Ilium, projected postiliac spine: absent (0); present (1). (KC183)
220. Pelvis, size of foramen ilioischiadicum and foramen acetabuli: foramen ilioischiadicum smaller or similar in size (0); foramen ilioischiadicum larger (1). (OH16)
221, Pelvis, fenestra ischiopubica (pelvis et os coxae, fenestra isquiopubica): very wide and closed at its caudal end (0); slit-like and open at its caudal end (1). (BG133)
222, Ischium, caudal extent in relation to postacetabular ilium: ischium shorter than ilium (0); ischium projects slightly beyond the ilium (1); ischium projected far caudal to ilium (2). (BG134)
223. Patella: absent, unossified, or a small ossicle (0); present as a large, block-like element (1). (KC 187)
224. Patella, sulcus m. ambiens: shallow groove (0); deep groove (1); perforated (2). (BG135)
225. Tibiotarsus, crista patellaris: slightly developed (0); well-projected (1); greatly elongated (2). (BG136)
226. Tibiotarsus, shaft, craniocaudal flattening: weak, midshaft craniocaudal depth greater than 75% mediolateral width (0); strong, midshaft craniocaudal depth equal to or less than 75% mediolateral width (1). (C169)
227. Tibiotarsus, sulcus extensorius: laterally positioned (0); close to midline (1); medially positioned (2). (K139)
228. Tibiotarsus, notch in distal edge of medial condyle (condylus medialis): present (0); absent (1). (AH38).
229. Tibiotarsus, lateral condyle (condylus lateralis) in lateral profile: ovoid (0); subcircular (1). (AH37)
230. Tibiotarsus, medial margin in distal view: margin is nearly straight (0); margin strongly convex (1). (KF242)
231. Tarsometatarsus, elongation index (proximodistal length/mediolateral width at proximal end): slender, EI>3.0 (0); shortened, 3.0>EI>2.5 (1); strongly shortened, 2.5>EI>2.0 (2); very strongly shortened, EI<2.0 (3). (BG138) Ordered.
232. Tarsometatarsus, proximal view, dorsoplantar compression (maximum lateromedial widthdorsoplantar width at middle point): weak, <2 (0); strong, >2 (1). (CHb42)
233. Tarsometatarsus, proximal view, size of cotylae: lateral bigger than medial (0); subequal (1); medial bigger than lateral (2). (CHb43)
234. Tarsometatarsus, lateral cotyla, dorsomedially expanded. In some taxa the dorsal edge of the lateral cotyla is dorsomedially deflected, expanding it slightly under the intercotylar prominence: absent (0); present (1). (CHb44)
235. Tarsometatarsus, lateral cotyla dorsal view, lateral projection: prominent (0); flattened (1). (CHb45)
236. Tarsometatarsus, medial cotyla, proximal view, pointed dorsal edge: absent (0); present (1). (CHb46)
237. Tarsometatarsus, medial cotyla, position: proximal (0); slightly dorsodistally deflected (1); strongly dorsodistally deflected (2). (CHb47)
238. Tarsometatarsus, enclosed hypotarsal canals (canales hypotarsi): absent (0); present (1). (BG141) Ordered. Note: While this character was modified by Chávez Hoffmeister (2014a) to associate state 1 with the enlarged hypotarsal canal present in Gavia, because Gavia was not used in our main phylogenetic analyses our character scores for this character follow Degrange et al. (2018).
239. Tarsometatarsus, proximal view, tendon of muscle flexor digitorum longus: groove (0); partially closed groove (1); canal (2). (CHb49)
240. Tarsometatarsus, proximal view, tendon of muscle flexor hallucis longus: groove, delimited medially by the crista lateralis flexor digitorum longus or the crista medialis flexor hallucis longus, and laterally by the crista lateralis flexor hallucis longus (0); groove, laterally open (1); poorly defined, inconspicuous or absent (2); canal (3). (CHb50) Modified: Wording for state 0 altered to be in accordance with terminology specified in Mayr (2016). Note that state 0 can be observed in Figure 8.5, Figure A10.2, A10.6, state 1 in Figure A10.1, A10.4-A10.5, A10.8, A10.9-A10.10 state 2 in Figure A10.7, A10.12-A10.15 and state 3 in Figure A10.3.
241. Tarsometatarsus, crista lateralis flexor digitorum longus: present (0); absent (1). (KF243) Modified: Definition wording altered to be in accordance with hypotarsus terminology specified by Mayr (2016).
242. Tarsometatarsus, medial hypotarsal crest, proximal view, bilobulated: absent (0); present (1). (CHb52)
243. Tarsometatarsus, proximal and plantar views, hypotarsal crests, crista lateralis flexoris digitorum longus, crista medialis flexor hallucis longus and crista lateralis flexoris hallucis longus: trisulcate, both crista lateralis flexoris digitorum longus and crista medialis flexoris hallucis longus are present (0); bisulcate, crista lateralis flexoris digitorum longus present and distinct (yet may be partially fused to the crista lateralis flexoris hallucis longus), crista lateralis flexoris hallucis longus present or vestigial, crista lateralis flexoris digitorum longus has subequal or greater plantar projection to crista lateralis flexoris hallucis longus (1); monosulcate, crista lateralis flexor digitorum longus is vestigial, indistinguishable or absent, crista lateralis flexoris hallucis longus is present or vestigial, crista lateralis flexoris hallucis longus projects further plantarly than crista lateralis flexoris digitorum longus in the instance that crests are present (2). (K158) Ordered. Modified: Wording of character definition and states changed to be in accordance with hypotarsus terminology in Mayr (2016), in order to more accurately and specify and label hypotarsus morphologies, and to reflect the range of penguin hypotarsus morphologies. It should be noted that bicanaliculate morphology as described by Mayr (2016) is classified as bisulcate (state 1) in this character for simplicity. State 0 can be seen in Figure A10.1, A10.3, state 1 in Figure 10.2, A10.4-A10.11, and state 2 in Figure A10.12-A10.15.
244. Tarsometatarsus, crista lateralis flexor hallucis longus, plantar view: enlarged and connected with crista medialis flexor digitorum longus (0); well-defined and parallel to proximodistal axis of tarsometatarsus (1); reduced, poorly defined and proximal to lateral foramen forming a diagonal ridge that over-hangs lateral foramen (2). (CHa224) Modified: Wording for definition and state 0 altered to be in accordance with terminology specified in Mayr (2016).
245. Tarsometatarsus, proximal view, plantar projection of crista lateralis flexor hallucis longus and/or crista lateralis flexor digitorum longus relative to crista medialis flexor digitorum longus: shorter (0); subequal (1). (KT203) Modified: Wording for definition altered to be in accordance with terminology specified in Mayr (2016).
246. Tarsometatarsus, collateral lateral ligament scar (impressio lig. collat. lat.): absent or inconspicuous (0); well-defined, creating a depression over the lateral surface (1); well-defined, creating a notch on the proximolateral vertex (2). (CHa219)
247. Tarsometatarsus, proximal vascular foramina, plantar view: medial foramen present, lateral foramen absent or vestigial (0); both foramina present (1); foramen vasculare proximale laterale present, foramen vasculare proximale mediale absent or vestigial (2). (K162)
248. Tarsometatarsus, lateral foramen, dorsal view: absent or vestigial (0); small (1); enlarged (2). (CHa229)
249. Tarsometatarsus, medial foramen, plantar view, opens distally to medial crest (opening for medial foramen proximalis vascularis distal to crista medialis hypotarsi): absent (0); present (1). (BG140)
250. Tarsometatarsus, medial foramen, medial view, perforating the medial hypotarsal crest (crista medialis hypotarsi/crista medialis flexor digitorum longus) perforated by opening for the medial foramen proximalis vascularis): absent (0); present (1). (B139) Modified: Wording in definition changed in accodance with hypotarsus terminology in Mayr (2016).
251. Tarsometatarsus, lateral edge, lateral view, strongly dorsoplantarly compressed: absent (0); present (1). (CHb61)
252. Tarsometatarsus, lateral edge, dorsal view: straight (0); concave (1). (A72)
253. Tarsometatarsus, dorsal view, medial margin, pronounced convexity: absent (0); present (1). (K157)
254. Tarsometatarsus, dorsal view, medial infracotylar groove: absent or poorly defined (0); present, proximal to the medial foramen, laterally open or limited by shallow tuberosities (1); present, laterally delimited by a crest or an osseus lamina that overhangs and partially occludes the medial foramen (2). (CHb64) Modified: Wording for state 1 and 2 expanded upon as per Chávez Hoffmeister (2014b).
255. Tarsometatarsus, dorsal view, lateral dorsal groove: absent or poorly defined (0); present, distal (1); present, along all the body (2). (CHb65)
256. Tarsometatarsus, dorsal view, medial dorsal groove: absent or barely perceptible (0); shallow groove (1); moderate groove (2); deep groove (3). (K159) Ordered.
257. Tarsometatarsus, dorsal, distal and plantar aspects, incisura intertrochlearis lateralis, foramen vasculare distale and canalis interosseus distalis: present, foramen vasculare distale opens proximal to the incisura intertrochlearis lateralis on the dorsal and plantar surfaces, and also the canalis interosseus distalis opens distally within the incisura intertrochlearis lateralis, separated by osseus ridges dorsally and plantarly from the foramen vasculare distale (0); present, foramen vasculare distale opens on the dorsal surface, and also distoplantarly, openings separated by a dorsally located osseus bridge, or may be connected forming a partially closed canal (1); absent (2). (K163) Ordered. Modified: Wording for state 0 and 1 altered.
258. Tarsometatarsus, intertrochlear notches, dorsal view: medial notch absent (0); medial notch deeper than lateral (1); subequal (2); lateral notch deeper than medial (3). (CHa233)
259. Tarsometatarsus, medial and lateral trochleae, dorsal view: medial trochlea shorter than lateral (0); lateral trochlea slightly shorter than medial (1); subequal (2). (CHa234)
260. Tarsometatarsus, lateral trochlea, dorsal view: laterally projected (0); straight (1); medially deflected (2). (K160)
261. Tarsometatarsus, medial trochlea, dorsal view, medial projection: strongly projected (0); moderately projected (1); planto-laterally deflected (2). (CHb71)
262. Tarsometatarsus, medial trochlea, dorsal view, presence of a neck between the trochlea and the tarsometatarsus body: absent (0); present (1). (CHb72)
263. Tarsometatarsus, lateral trochlea, distal view: dorsally aligned with intermediate trochlea (0); dorsally deflected (1); plantarly deflected (2). (KT211)
264. Tarsometatarsus, medial trochlea, distal view, strongly plantarly deflected: absent (0); present (1). (A73)
265. Tarsometatarsus, lateral trochlea, distal view, laterally deflected: absent (0); present (1). (LZ2366)
266. Tarsometatarsus, medial trochlea, plantar view, orientation of the medial and lateral carinae on the plantar-most articulation surface of trochlea metatarsi III: strongly distoproximally tapered trochlear rims (0); weakly distoproximally tapered trochlear rims (1); parallel-sided trochlear rims (2). (This study). This character relates to a distinguishing feature described by Mayr et al., (2018), differentiating tarsometatarsi of Waimanu manneringi and Muriwaimanu tuatahi .
267. Pedal digit I: small, with metatarsal I and single phalanx both present (0); metatarsal I reduced to an ossicle, claw represented by a minute ossicle or lost (1); metatarsal I absent (2). (KF245) Ordered.
268. M. latissimus dorsi, pars cranialis, accessory slip: absent (0); present (1). (BG143)
269. M. latissimus dorsi, pars cranialis and pars caudalis: separated (0); fused (1). (BG144)
270. M. latissimus dorsi, pars metapatagialis, development: wide (0); intermediate (1); narrow (2). (BG145) Ordered.
271. M. serratus profundus, cranial fascicle: absent (0); present (1). (BG146)
272. M. deltoideus, pars propatagialis, subdivision in superficial and deep layers: undivided (0); divided (1). (BG147)
273. M. deltoideus, pars major: triangular or fan-shaped (0); strap-shaped (1). (BG148)
274. M. deltoideus, pars major, caput caudale: short (0); intermediate (1); long (2). (BG149) Ordered.
275. M. deltoideus, pars minor, origin on the clavicular articulation of the coracoid: absent (0); present (1). (BG150)
276. M. ulnometacarpalis ventralis: absent (0); present (1). (BG151)
277. M. iliotrochantericus caudalis: narrow (0); wide (1). (BG152)
278. M. iliofemoralis, origin: tendinous (0); partially tendinous and partially fleshy (1); totally fleshy (2). (BG153) Ordered.
279. M. flexor perforatus digitis IV, rami II-III: free (0); fused (1). (BG154)
280. M. flexor perforatus digitis IV, rami I-IV: free (0); fused (1). (BG155)
281. M. flexor perforatus digitis IV, insertion of middle rami: on phalanx 3 (0); on phalanx 4 (1). (BG156)
282. M. latissimus dorsi, pars caudalis, additional origin from dorsal process of vertebrae: absent (0); present (1). (BG157)
Other soft tissue:
283. Oral mucosa (bucca, tunica mucosa oris), buccal papillae group on the medial surface of the lower jaw (ramus mandibularis) at the level of the rictus: small number of rudimentary papillae with no clear arrangement (0); large, elongated papillae with no clear arrangement (1); two clear rows of short conical papillae (2). (BG158)
284. Tracheal rings: single (0); bifurcated (1). (KC219)
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