Branta rhuax

[another specialist]

Geochen rhuax
Wetmore 1943
Holocene of Hawaii, Hawaiian Islands
Primary materials: Type: Right tibiotarsus fragment

Alexander Wetmore,
An extinct goose from the island of Hawaii
The Condor 45, 4 (1943): 146-148

[another specialist]

source for above

www.ornitaxa.com/SM/Fossil/FossilAnati.htm

[cryptodude100]

Geochen Rhuax appears to have been about as large as the living Cape Barren Goose.

[dysmorodrepanis]

Probably. But any details about this bird are really guesswork. Not even its relationships are identifiable. All that can be said is that it is possibly an ancestor of the moa-nalos (and just as possibly something completely different), and most likely died out before humans settled the islands.

[cryptodude100]

That's true. I'm just preferring to an article and a few descriptions of the bird.

[another specialist]

Genus Geochen Wetmore, 1943
Type species: Geochen rhuax Wetmore, 1943; by monotypy and "new genus
and species" convention.
Includeds peciesT: ype specieso nly.
Distribution: Hawaii: Kau District.
Emended diagnosis:L arger and more robust than Hawaiian populations of
Branta, including the robust fossil forms. Differs from Branta and from the moanalos
in having the proximal articular surface of the tibiotarsus oriented lateromedially,
rather than having its long axis in an antero-posterior plane, and also
in having the head and trochanter of the femur more sharply set off by a groove.
Differs further from the moa-nalos in having a shorter neck of the femur and a
more sharply rising trochanter.

Geochen rhuax Wetmore, 1943
Geochen rhuax Wetmore, 1943:146.
Holotype: Very imperfect right tibiotarsus, USNM 16740.
Type locality: Near Kaumaikeohu, above Pahala, Kau District, Island of Hawaii.
Distribution: Known only from the type locality.
Paratypes: Very fragmentary remains of right and left femora, fibula, and pelvis
associated directly with the rolotype and doubtless belonging to the same individual.
Remarks: This was the first fossil bird to be described from the Hawaiian Islands,
the type material having been found in 1926 in the course of a public works
excavation, at a depth of 25 m under a lava flow (Wetmore 1943). From their
very friable and warped appearancet,h e bonesw ere almost certainlyh eatedu ntil
glowing, with all organic material in the bone having been combusted. Although
Wetmore (1943) considered Geochen to be more closely related to the Australian
genusC ereopsisth an to Branta or other goose-likea natids, we regardt he material
as being much too imperfect for determining the affinities of the bird. We can
only hope that additional specimens will be found that can unambiguously be
identified with the type. Otherwise, this will simply have to be regarded as a form
of doubtful relationships.

Storrs L. Olson & Helen F. James,
Descriptions of thirty-two new species of birds from the Hawaiian Islands: Part I. Non-Passeriformes
Ornithological Monographs 45 (1991)
The American Ornithologists' Union, Washington D.C.

elibrary.unm.edu/sora/om/om045.pdf

[another specialist]

VERY LARGE HAWAII GOOSE
"Large Hawaii goose" Olson and James, 1982b:35; 1984:772.
Material.' Associated fragmentary material consisting of the proximal end of a
right ulna, posterior portion of a sacrum and other pelvic fragments, a vertebra,
9 pedal phalanges, and other unidentified scraps, USNM 389448-389469. Incomplete cranium lacking most of the right sidea nd basioccipital B, PBM158620;

fragment of proximale nd of right femur, BPBM 158621. Six uncataloged lots of
various very poorly preserved bones, probably representing six individuals.
Distribution: Hawaii: westerns ide of the island. The first specimens were from
two lava tubes in the vicinity of Kailua, North Kona District. The uncataloged
lots are from a lava tube on Kahua Ranch, North Kohala District, at an elevation
of about 1,133 m.
Measurements(m m): Cranium: approximate width at nasofrontal hinge, 30.
Tibiotarsus length from proximal articular surface2, 05. Tarsometatarsu length, ca. 110.
Remarks:There are scarcely any comparable elements among theses amples of
fragment arbyone, but all the material comes from a very large goose larger
than
any of the moa-nalos or the various forms of Branta, so we assume that they
represent one and the same species The wing was reduced, but not nearly to the extent as in the moa-nalos.

Storrs L. Olson & Helen F. James,
Descriptions of thirty-two new species of birds from the Hawaiian Islands: Part I. Non-Passeriformes
Ornithological Monographs 45 (1991)
The American Ornithologists' Union, Washington D.C.


elibrary.unm.edu/sora/om/om045.pdf

[another specialist]

Fig. 1. A map of the main Hawaiian Islands with skulls of two moa-nalos (a, Chelychelynechen quassus; b, Thambetochen chauliodous) and the three Hawaiian geese evaluated in this study [B. sandvicensis (nene), B. hylobadistes (nene-nui), and the undescribed giant Hawaii goose]. Fossils of the giant Hawaii goose have been found only on the island of Hawaii (1, 2). Moa-nalos were found only on the older islands from Maui to Kauai (1). Arrows show that the nene, B. sandvicensis, and nene-like (B. hylobadistes and relatives) geese were widely distributed among the main islands.

[another specialist]

Fig. 2. Skulls and mandibles in lateral view. (a) B. canadensis maxima (USNM 555497); (b) giant Hawaii goose (BPBM 179440); (c) B. hylobadistes (BPBM PPBH7); (d) B. sandvicensis (USNM 557998). The length of the giant Hawaii goose skull (b) is 127.6 mm.



Fig. 3. Left ulna and tibiotarsus. (a) B. canadensis maxima (USNM 555497); (b) giant Hawaii goose (BPBM 179440); (c) B. hylobadistes (BPBM PPBH7); (d) B. sandvicensis (USNM 557998).

[another specialist]

sordes said:

Here is a link with a very nice but small life reconstruction: www.oahunaturetours.com/nenenui.html

Illustration by Julian Hume

In the foreground is the nene, or Hawaiian goose (Branta sandvicensis). The Nene-nui, or greater nene (Branta hylobadistes), is at center and the Giant Hawaii goose (an undescribed species) is at the back. The nene is an endangered species; the other two species are extinct and known only from fossils. All three evolved in the Hawaiian Islands from an ancestor much like the modern Canada goose.

This species was described from bones found at Barbers Point, Oahu. It is similar to the new species, Branta hylobadistes which was described from fossils found at Auwahi cave on Maui.The scientific name means woods-walker in Greek , a reference to this species former abundance in forested areas and its dependence on foot power because of its reduced flight capabilities. It was larger and more robust then the Nene, Branta sandvicensis.

Please do what you can to save the native Hawaiian forest bird species that remain.

Aloha,
Michael Walther

[cryptodude100]

What is known about the linear dimensions of the Large Hawaii goose compared to the Canada Goose or Nene?

[another specialist]

cryptodude100 said:

What is known about the linear dimensions of the Large Hawaii goose compared to the Canada Goose or Nene?

If you look and read post 3 and 4 you can see the comparisions of skull and leg bones plus a drwaing based on this measurements.

[sordes]

And if he had read the article, he would know that this bird was a bit over 8kg in average.

[another specialist]

sordes said:

And if he had read the article, he would know that this bird was a bit over 8kg in average.

Thanks Sordes I forgot to mention the article

[cryptodude100]

Does anyone how tall the bird was in life?

[Deleted]

cryptodude100 said:

What is known about the linear dimensions of the Large Hawaii goose compared to the Canada Goose or Nene?

anotherspecialist said:

If you look and read post 3 and 4 you can see the comparisions of skull and leg bones plus a drwaing based on this measurements.

anotherspecialist said:

If You just take a look on this picture You may see three birds, one is the Nene (the bird in front), the largest is the large hawaiian bird without a name. If You now just find out how large the Nene is, You can very, very easily find out how large the Giant Hawaiian Goose once was, namely about 1 m (at the head).

The bird in the middle is the Nene nui (Branta hylobadistes), and perhaps You can now just estimate by Yourself how large this bird once was, right ?

*off topic* Did the others of You ever heard of trolls ? ? ? Think about that question for a while ! Thank You !

[Carlos]

Never heard of trolls in real life, but I'm glad to hear of you here again, Alex.

[cryptodude100]

thanks

[another specialist]

here is the whole pdf file

si-pddr.si.edu/dspace/bitstream/10088/355/1/Paxinos2002a.pdf

[Melanie]

Geochen rhuax has been redescribed as Branta rhuax

Olson 2013. Hawaii's first fossil bird: history, geological age, and taxonomic status of the extinct goose Geochen rhuax Wetmore (Aves: Anatidae). P Biol Soc Wash 126(2): 161–168.

www.bioone.org/doi/abs/10.2988/0006-324X-126.2.161