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Post by Melanie on Jun 5, 2005 22:11:43 GMT
Phil MILLENER excavated in a small cave in Chatham Islands, and recovered much of a skeleton of Pachyanas chathamica, including the hitherto unknown sternum and complete bill - premaxilla and mandible were known only in part before - including a mandibular ramus which Phil found in a previous trip to Chatham. Phil is rewriting a paper of which Ron SCARLETT wrote a draft some years ago.
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Post by Melanie on Jun 5, 2005 22:20:33 GMT
Pachyanas chathamica (Chatham Is duck) (Group I)
Confined to Chatham Is. Marine: a 'steamer duck'
analogue, feeding on molluscs and crustaceans
obtained by diving. Nests in holes among rocks and in
dense vegetation. Confiding, easily caught. Extinction
through direct predation by humans.
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Post by another specialist on Jun 6, 2005 3:40:22 GMT
Pachyanas chathamica
Oliver 1955
Holocene of Chatham Islands, sw Pacific Ocean
Primary materials: Type: Cranium
Brian Gill & Paul Martinson,
New Zealand's extinct birds
(1991)
Random Century, New Zealand
See also:
Bradley C. Livezey,
A phylogenetic classification of waterfowl (Aves: Anseriformes), including selected fossil species
Annals of Carnegie Museum 66 (1997): 457-496
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Post by another specialist on Nov 2, 2005 10:03:15 GMT
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Post by dysmorodrepanis on Dec 15, 2005 17:20:42 GMT
Finsch writes in J.Ornithol. 22 p.223 of a "strange duck", "seen by Travers on his first visit to the Chatham Islands" which had "scarlet spots/blotches on the wings" (literally "Flecken" - can mean anything from stippling to a large blotch). His reference is p.247 of: Hutton, FW 1872 Notes on some birds from the Chatham Islands collected by HH Travers Esq., with descriptions of two new species Ibis (S3) 2, p.243-250 A primary source could be either: Travers, H.H. 1869: On the Chatham Island. Transactions and Proceedings of the New Zealand Institute 1: 119-127 or Travers, W.T.L. 1872: Notes on the Chatham Islands, extracted from letters from Mr H.H. Travers. Transactions and Proceedings of the New Zealand Institute 4: 63-66. or possibly even Travers. H.H.; Travers, W.T.L. 1873: On the birds of the Chatham Islands by H.H. Travers with introductory remarks on the avi-fauna and flora of the islands in relation to those in New Zealand. Transactions and Proceedings of the New Zealand Institute 5: 212-222. However, subfossil remains of a Tadorna (cf. T. variegata) and an Anas (cf. A. chlorotis) have been found on the Chatham Islands (Smithsonian Contrib.Zool.89, p.85-109). We do not have an article on these birds. I wonder whether the ruddy tertiaries of a Tadorna variegata-like bird ( upload.wikimedia.org/wikipedia/commons/thumb/9/94/Paradieskasarka01_m.jpeg/450px-Paradieskasarka01_m.jpeg) could be mistaken as "scarlet blotches" from a distance. To be sure, the wings of P. chathamica were very small and inconspicuous. But I have not seen the primary sources, and Finsch lists this bird as "Anas" or "Querquedula sp?", so it seems to be a smaller bird. The Anas forms of the NZ region do not, however, have any peculiar reddish wing markings. |
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Post by dysmorodrepanis on Dec 15, 2005 19:44:24 GMT
The original note by Travers is given by Finsch, J.Ornithol. 18 p357: "During my journey round Chatham-Island I saw a peculiar teal on one of the lagoons, near the Red-Bluff. This bird hat bright scarlet markings on the wings. I fired at it, but owing to the great dampness of the weather, the gun I had with me hung fire, and I missed the bird. I never saw another specimen and was informed that it is very uncommon."
Whether P. chathamica could be described as a "teal" from its coloration is unknown. From its size, it was quite a bit too large (more like a mallard, but probably much bulkier). The description excludes the Tadorna, however; thus it can only refer to the extinct Anas (which was between P. chathamica and a typical "teal" in size but on biogeographic grounds is not very likely to have had any "bright scarlet markings" on its wing) or P. chathamica.
For comparison, "teals" are generally between 35 and 50 cm total length. "Ducks" (inclugind mallard, gadwall, shoveler etc) are larger, 50-65cm. Tadorna variegata is half as long again as a teal, and as it should have been known to Travers (didn't check it though, but it seems unlikely that he, a bird skin dealer by trade, did not know it), he would have called the Chatham Shelduck, had he met with it, a "shelduck", and surely not a "teal".
Thus, there seem 2 possibilities:
1) Pachyanas chathamica or Anas cf. chlorotis were still extant in the late 1860s
2) Travers met with a stray individual of some unidentifiable species.
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Post by another specialist on Dec 25, 2005 17:55:39 GMT
the Chatham island duck was described in 1955 from subfossil bones found at the chatham islands. It had a very robust skull and was stoutly built, perhaps weighing 2kg - twice as much as a grey dck anas superciliosa. The Chatham island duck was probably flightless, and may have been marine, feeding on crabs and shellfish caught close to the shore. Bones have been found in maori kitchen middens.
New Zealand's Extinct Birds
Brian Gill and Paul Martinson
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Post by dysmorodrepanis on Nov 18, 2006 2:39:34 GMT
The "Transactions and Proceedings" are online for free, as fulltext! rsnz.natlib.govt.nz/journals/rsnz/allvolumes.htmlThe dates given above are one year too late, and the pages are way off. It is the first reference, on page 178. The text is just as given above. Maori or Moriori? The distinction is important. Is there anything in "Lost World of the Moa" on this? |
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Post by another specialist on Nov 18, 2006 7:58:08 GMT
Definately correct from this book
New Zealand's Extinct Birds
Brian Gill and Paul Martinson
But we can see if anything else can be found in other books.
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Post by cryptodude100 on Dec 28, 2006 17:11:02 GMT
what is known about the skull?
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Post by sebbe67 on Dec 30, 2006 13:21:20 GMT
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Post by another specialist on Sept 8, 2008 11:55:20 GMT
 The Lost World of the Moa By T. H. Worthy, Richard N. Holdaway, Rod Morris |
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Post by Melanie on Aug 30, 2013 15:18:06 GMT
Some news about the Chatham Duck Ancient mitochondrial genome reveals unsuspected taxonomic affinity of the extinct Chatham duck (Pachyanas chathamica) and resolves divergence times for New Zealand and sub-Antarctic brown teals Kieren J. Mitchella, Corresponding author contact information, E-mail the corresponding author, Jamie R. Woodb, R. Paul Scofieldc, Bastien Llamasa, Alan Coopera a Australian Centre for Ancient DNA, School of Earth and Environmental Sciences, University of Adelaide, North Terrace Campus, South Australia 5005, Australia b Landcare Research, PO Box 69040, Lincoln, Canterbury 7640, New Zealand c Canterbury Museum, Rolleston Avenue, Christchurch, New Zealand Abstract The Chatham duck (Pachyanas chathamica) represented one of just three modern bird genera endemic to the Chatham archipelago (situated ∼850 km east of New Zealand) but became extinct soon after humans first settled the islands (c.13th - 15th centuries AD). The taxonomic affinity of the Chatham duck remains largely unresolved; previous studies have tentatively suggested placements within both Tadornini (shelducks) and Anatini (dabbling ducks). Herein, we sequence a partial mitochondrial genome (excluding the D-loop) from the Chatham duck and discover that it was a phenotypically-divergent species within the genus Anas (Anatini). This conclusion is further supported by a re-examination of osteological characters. Our molecular analyses convincingly demonstrate that the Chatham duck is the most basal member of a sub-clade comprising the New Zealand and sub-Antarctic brown teals (the brown teal [A. chlorotis], Auckland Island teal [A. aucklandica] and Campbell Island teal [A. nesiotis]). Molecular clock calculations based on an ingroup fossil calibration support a divergence between the Chatham duck and its sister-taxa that is consistent with the estimated time of emergence of the Chatham Islands. Additionally, we find that mtDNA divergence between the two sub-Antarctic teal species (A. aucklandica and A. nesiotis) significantly pre-dates the last few glacial cycles, raising interesting questions about the timing of their dispersal to these islands, and the recent phylogeographic history of brown teal lineages in the region. www.sciencedirect.com/science/article/pii/S1055790313003394 |
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Post by Deleted on Sept 7, 2013 7:01:37 GMT
Hi there!
So it's rather Anas chathamica, right?
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Post by Melanie on Sept 7, 2013 10:39:41 GMT
Hi there! So it's rather Anas chathamica, right? It is in the same clade as A. nesiotus and A. chlorotis but Pachyanas is still a sister taxon of Anas. |
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Post by surroundx on Sept 10, 2013 15:00:59 GMT
Hi there! So it's rather Anas chathamica, right? Yes  |
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Post by Melanie on Jul 20, 2014 20:17:52 GMT
Musings about Chatham Island’s extinct duck, “Pachyanas”
Murray Williams
68 Wellington Road, Paekakariki, New Zealand. murraywilliams@paradise.net.nz
A recent genetic study identified Chatham Island’s extinct duck Pachyanas chathamica as more closely related to New Zealand and sub-Antarctic brown teals than to any other modern waterfowl, and calibrated their divergence as occurring 0.69–1.80 mya. The modern (but sadly no longer) occurrence of brown teal on Chatham Island was a belated colonisation which, perhaps, we could view as akin to the takahe and pukeko example on mainland New Zealand. Pachyanas arose from the same clade of ducks that gave rise to New Zealand and sub-Antarctic brown teals (it is not a descendant of brown teal) but became much bigger than brown teal, possibly a unique example of an island duck being larger (not smaller) than its mainland relative. Reclassified as an Anas, it may also have been one of the largest known of that genus, certainly exceeding the largest of the living Anas ducks (mallard, spotbill). Why? I will compare some of its skeletal characters with selected other ducks, present a scattering of evidence to indicate its possible ecology, and offer a (barely plausible) hypothesis to explain its apparent size.
Abstracts from the 2014 New Zealand Bird Conference, Palmerston North. (http://www.osnz.org.nz/sites/osnz.org.nz/files/publications/2014%20Abstracts.pdf)
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Post by Melanie on Sept 21, 2015 22:36:12 GMT
Some news about the Chatham Duck Ancient mitochondrial genome reveals unsuspected taxonomic affinity of the extinct Chatham duck (Pachyanas chathamica) and resolves divergence times for New Zealand and sub-Antarctic brown teals Kieren J. Mitchella, Corresponding author contact information, E-mail the corresponding author, Jamie R. Woodb, R. Paul Scofieldc, Bastien Llamasa, Alan Coopera a Australian Centre for Ancient DNA, School of Earth and Environmental Sciences, University of Adelaide, North Terrace Campus, South Australia 5005, Australia b Landcare Research, PO Box 69040, Lincoln, Canterbury 7640, New Zealand c Canterbury Museum, Rolleston Avenue, Christchurch, New Zealand Abstract The Chatham duck (Pachyanas chathamica) represented one of just three modern bird genera endemic to the Chatham archipelago (situated ∼850 km east of New Zealand) but became extinct soon after humans first settled the islands (c.13th - 15th centuries AD). The taxonomic affinity of the Chatham duck remains largely unresolved; previous studies have tentatively suggested placements within both Tadornini (shelducks) and Anatini (dabbling ducks). Herein, we sequence a partial mitochondrial genome (excluding the D-loop) from the Chatham duck and discover that it was a phenotypically-divergent species within the genus Anas (Anatini). This conclusion is further supported by a re-examination of osteological characters. Our molecular analyses convincingly demonstrate that the Chatham duck is the most basal member of a sub-clade comprising the New Zealand and sub-Antarctic brown teals (the brown teal [A. chlorotis], Auckland Island teal [A. aucklandica] and Campbell Island teal [A. nesiotis]). Molecular clock calculations based on an ingroup fossil calibration support a divergence between the Chatham duck and its sister-taxa that is consistent with the estimated time of emergence of the Chatham Islands. Additionally, we find that mtDNA divergence between the two sub-Antarctic teal species (A. aucklandica and A. nesiotis) significantly pre-dates the last few glacial cycles, raising interesting questions about the timing of their dispersal to these islands, and the recent phylogeographic history of brown teal lineages in the region. www.sciencedirect.com/science/article/pii/S1055790313003394It's now free available www.researchgate.net/publication/256330827_Ancient_mitochondrial_genome_reveals_unsuspected_taxonomic_affinity_of_the_extinct_Chatham_duck_%28Pachyanas_chathamica%29_and_resolves_divergence_times_for_New_Zealand_and_sub-Antarctic_brown_teals |
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Post by Sebbe on Dec 22, 2015 20:19:54 GMT
Size and flight capability of Anas chathamica, an extinct duck from Chatham Island, New ZealandMeasurements of major bones from Chatham Island’s extinct duck Anas chathamica (formerly placed in Pachyanas) were used to estimate the duck’s likely mass and flight capability. Mass estimates derived from published regression equations relating least femur circumference to body mass for volant birds ranged between 1,500–2,300 g, and those based upon tibiotarsus least circumference ranged between 1,670–2,400 g, providing an overall average mass estimate of c. 1,900 g. The bimodal size-frequency distribution of femur lengths, used to establish putative sexes, indicated a c. 11% sexual body mass dimorphism. Distal wing bones were disproportionately short when compared with flighted Anas ducks, and were similar to those of the related, flightless Auckland Island Teal A. aucklandica and Campbell Island Teal A. nesiotis. A humerus length/femur length ratio of c. 1.40 is below the lowest ratio recorded for any flighted Anseriformes (c. 1.60), and also lower than those for flightless steamer ducks Tachyeres sp. (c. 1.50), but above that of three flightless Anas sp. (c. 1.30). Carina (keel) area relative to carina or sternum length was less than for any flighted New Zealand Anas sp. but greater than for the Auckland Island and Campbell Island Teals. In combination, these characteristics indicate that the Chatham Island Duck was flightless, and also the largest known of its genus. wildfowl.wwt.org.uk/index.php/wildfowl/article/view/2627
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Post by surroundx on Jun 13, 2017 17:10:03 GMT
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