A review of Australian fossil penguins (Aves: Sphenisciformes)
Author
Park, Travis
Author
Fitzgerald, Erich M. G.
text
Memoirs of Museum Victoria
2012
2012-12-31
69
309
325
https://museumsvictoria.com.au/collections-research/journals/memoirs-of-museum-victoria/volume-69-2012/pages-309-325/
journal article
10.24199/j.mmv.2012.69.06
1447-2554
12212344
Pseudaptenodytes macraei
Simpson, 1970
Holotype
.
Partial left humerus (
NMV
P26668
). (
Fig. 11
;
Table 2
).
Type locality.
Spring Creek
near
Minhamite
,
41 km
southeast of
Hamilton
,
Victoria
(
37°58'S
,
142°23'E
)
.
Horizon and age
. The
holotype
is derived from the Goodwood Formation, a green-grey marly fine sand with abundant pebbles (
Gill, 1964:332
). The macroinvertebrate assemblage is similar to that of the Upper Miocene–Lower Pliocene Black Rock Sandstone (
Gill, 1964
;
Simpson, 1970
), and the Goodwood Formation is possibly laterally equivalent to the Upper Miocene–Lower Pliocene Grange Burn Formation (
Fitzgerald, 2004
).
Referred material
. A partial right carpometacarpus (
NMV
P27055) and a partial left carpometacarpus (
NMV
P27056) were tentatively referred to this species (
Simpson, 1970
) (
Fig. 15
;
Table 2
). Both specimens were derived from the Upper Miocene–Lower Pliocene Black Rock Sandstone at Beaumaris.
Diagnosis.
Simpson (1970)
noted the very close similarity of
Pseudaptenodytes macraei
to
Aptenodytes patagonicus
, both in terms of size and the features of the proximal end of the humerus. Nevertheless,
P. macraei
differs from
Aptenodytes
by having a humerus with: a more sigmoid shaft; a smaller volume of the fossa pneumotricipitalis; a distinctly oval opening of the internal division of the fossa pneumotricipitalis; and a rounded cranial margin lacking a distinct ‘preaxial angle’ (
Acosta Hospitaleche et al., 2008
:
Fig. 5
, char. 11). It further differs from
A. forsteri
by lacking the pit for ligament insertion on the proximal surface adjacent to the head (Ksepka et al., 2006:
Fig. 8
). In
A. patagonicus
this feature is variable (Ksepka et al., 2006).
Remarks
. Despite the similarities of the
type
specimen to
Aptenodytes patagonicus
,
Pseudaptenodytes macraei
is not ancestral to it or any of the modern species (
Simpson, 1970: 20
). Although similar, the autapomorphies of
NMV
P26668 preclude this specimen from referral to
Aptenodytes
or any extant genera. We consider
P. macraei
to be a distinct taxon established on the basis of a diagnostic
type
specimen.
Figure 12.
Sphenisciformes
indet. partial left coracoid, NMV P24065: A, dorsal view; B, ventral view.
?
Pseudaptenodytes minor
Simpson, 1970
Holotype
.
Partial right humerus (
NMV
P26669
). (
Fig. 14
;
Table 2
).
Type locality.
East of Rickett’s Point
on the western shore of
Beaumaris Bay
, northeast shore of
Port Phillip Bay
,
Victoria
(
37°59'S
,
145°03'E
)
.
Horizon and age.
Black Rock Sandstone, which consists of a basal layer of phosphatic and ferruginous intraclasts overlain by calcareous sandstone (
Dickinson and Wallace, 2009
). Planktonic foram and molluscan biostratigraphy indicate a Late Miocene–Early Pliocene age range, which is corroborated by Sr dates of 5.0–6.2 Ma (
Dickinson and Wallace, 2009
).
Referred material.
Distal end of right humerus (
NMV
P26677), proximal end of left humerus, (
NMV
P26671), proximal end of left humerus (
NMV
P26676), right humerus (
NMV
P26670), right humerus (
NMV
P27057), partial right carpometacarpus (
NMV
P27058), right carpometacarpus (
NMV
P26903) (
Fig. 13
;
Table 2
). All referred material was collected from the Upper Miocene–Lower Pliocene Black Rock Sandstone at Beaumaris.
Diagnosis
. Differs from
Pseudaptenodytes macraei
by having: a more slender and less sigmoid shaft; and a less expanded distal section (
Simpson, 1970
). It also differs by having a distinct angle on the cranial margin, although this angulation is still less than that of any modern penguin (
Simpson, 1970
).
Remarks
.
Simpson (1970)
notes the similarities between?
Pseudaptenodytes minor
and
Paraptenodytes robustus
yet the
holotype
of?
P. minor
is too incomplete to permit meaningful comparisons. The lack of diagnostic morphology in the type specimen of?
P. minor
has resulted in Ksepka and
Clarke (2010)
referring this taxon to
Sphenisciformes
indet. More completely preserved material is required to confirm or reject the placement of this species in
Pseudaptenodytes
. The additional material referred by
Simpson (1970)
to?
P. minor
displays little overlap in morphology with the
holotype
(
NMV
P26669). Furthermore, it is only on the basis of the referred material that the
holotype
was designated a species of
Pseudaptenodytes
. We therefore recommend restricting the concept of?
P. minor
to the
holotype
. All referred material should be considered
Sphenisciformes
indet. pending further study.