Talpanas, Iwaniuk, Andrew N., Olson, Storrs L. & James, Helen F., 2009

Iwaniuk, Andrew N., Olson, Storrs L. & James, Helen F., 2009, Extraordinary cranial specialization in a new genus of extinct duck (Aves: Anseriformes) from Kauai, Hawaiian Islands, Zootaxa 2296, pp. 47-67 : 48-56

Genus Talpanas new genus (Olson & James)

Type species. Talpanas lippa Olson and James , new species, by original designation. Included species. Type species only.

Distribution. Kauai, Hawaiian Islands.

Etymology. L. talpa (f.) a mole, plus anas (f.), a duck, in allusion to the greatly reduced size of the eyes. The gender is feminine. Among mammals, the closest analog of the new genus of duck in the appearance of the cranium, as well as in the similarity in trigeminal enlargement ( Home 1802), is the platypus ( Ornithorhynchus anatinus ), an alternate vernacular of which among Australian colonists was "duck-mole." The reduced eyes and poor vision of moles ( Talpidae ) are well known.

Diagnosis. Anatidae with braincase very broad and dorsoventrally compressed, with greatly reduced orbits. Maxillo-mandibular foramen and foramen n. olfactorii greatly enlarged relative to all other waterfowl. The orbit is greatly reduced in size and laterally displaced, allowing the nasal cavity to extend caudally and directly abut the brain cavity. There is consequently no mesethmoidal sulcus for the olfactory nerves, whereas in other anatids the orbit separates the olfactory and brain cavities, requiring long olfactory nerves to traverse the orbit. The nasal gland depressions are seated against extensive flat surfaces of the frontal that face laterad, whereas in most other Anatidae these depressions face dorsad.

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(mm2) (mm2) (mm2) (°) Anas versicolor 4 4.5 6.8 25.6 23.3 Anas wyvilliana 4 4.5 7.9 31.6 23.2 Anser albifrons 4 3.6 9.2 59.1 22.4 Anser anser 4 4.7 12.4 65.5 29.0 Anser caerulescens 4 4.7 10.2 53.7 26.0 Anser canagicus 4 4.9 10.2 53.3 22.0 Anser cygnoides 2 8.1 10.6 74.0 26.5 Anser fabalis 6 3.9 11.8 53.4 26.4 Anser indicus 2 3.7 12.1 59.1 24.7 Anser rossii 4 3.0 8.9 39.9 22.1 Anseranas semipalmata 3 6.2 9.7 45.6 26.0 Aythya affinis 5 4.0 7.4 32.2 27.2 Aythya americana 4 4.1 8.5 43.9 27.4 Aythya australis 2 2.8 8.8 45.0 25.2 Aythya baeri 1 3.0 10.2 38.7 26.9 Aythya collaris 4 3.3 8.9 36.5 26.1 Aythya ferina 4 5.4 8.5 47.5 28.4 Aythya fuligula 4 3.2 8.3 35.4 25.5 Aythya innotata 1 2.6 9.8 35.0 27.7 Aythya marila 4 4.3 7.3 41.4 26.3 Aythya novaeseelandiae 1 4.1 9.5 26.9 23.6 Aythya nyroca 3 4.0 9.2 31.4 26.9 Aythya valisineria 4 5.1 10.3 49.5 26.9 Biziura lobata 2 6.0 12.9 49.5 34.5 Branta bernicla 4 2.5 8.8 45.5 23.1 Branta canadensis minima 4 1.9 9.1 44.8 28.9 Branta canadensis moffitti 3 4.9 16.2 64.5 23.4 Branta canadensis taverneri 3 4.9 13.6 49.0 26.9 Branta hylobadistes 1 4.9 10.8 52.0 30.1 Branta leucopsis 1 2.6 13.0 52.5 22.8 Branta ruficollis 3 2.6 9.3 37.6 26.9 Branta sandvicensis 3 3.0 10.9 57.9 26.4 Branta sp.* 2 5.4 13.7 87.6 24.0 Bucephala albeola 4 2.8 7.5 25.6 27.5 Bucephala clangula 4 2.5 10.7 39.5 24.2 Bucephala islandica 3 3.0 10.2 41.4 26.6 Cairina moschata 3 4.0 18.8 58.1 26.4 Cairina scutulata 4 5.8 14.6 56.0 25.3 Calonetta leucophrys 2 2.7 6.5 24.1 27.3 Cereopsis novaehollandiae 4 3.8 13.8 51.0 26.6

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(mm2) (mm2) (mm2) (°) Chenonetta jubata 3 1.6 8.2 30.1 26.5 Chloephaga hybrida 4 3.1 10.4 48.3 22.5 Chloephaga melanoptera 3 3.3 12.3 45.7 21.1 Chloephaga picta 3 2.7 12.7 46.8 19.2 Chloephaga poliocephala 3 2.3 13.0 40.4 15.8 Chloephaga rubidiceps 1 1.5 10.0 39.9 14.6 Clangula hyemalis 5 2.2 9.1 32.1 20.4 Coscoroba coscoroba 4 8.1 11.4 59.7 16.7 Cyanochen cyanopterus 4 3.0 12.5 48.3 19.4 Cygnus atratus 4 7.8 12.9 83.2 20.9 Cygnus buccinator 5 9.4 12.4 106.8 24.4 Cygnus columbianus 4 8.2 12.1 83.2 22.3 Cygnus cygnus 1 8.8 17.7 130.1 22.2 Cygnus melancoryphus 4 8.8 9.3 80.3 21.1 Cygnus olor 4 10.9 15.4 107.2 26.1 Dendrocygna arborea 4 5.4 11.3 42.6 23.6 Dendrocygna arcuata 4 4.7 7.3 35.2 19.8 Dendrocygna autumnalis 4 4.6 9.6 32.5 22.6 Dendrocygna bicolor 4 4.4 8.3 36.8 26.4 Dendrocygna eytoni 2 3.9 9.1 32.8 22.2 Dendrocygna guttata 4 5.5 9.0 29.8 25.9 Dendrocygna javanica 2 4.8 8.3 34.1 -

Dendrocygna viduata 4 3.5 8.5 30.8 22.1 Heteronetta atricapilla 2 3.7 5.1 25.4 24.0 Histrionicus histrionicus 4 1.4 9.5 33.0 26.1 Hymenolaimus malacorhynchus 1 6.3 10.5 45.5 22.9 Lophodytes cucullatus 5 1.7 11.2 31.2 26.5 Lophonetta specularoides 4 5.5 7.8 39.1 24.5 Malacorhynchus membranaceus 1 5.9 5.2 27.4 20.4 Marmaronetta angustirostris 4 2.2 6.2 28.6 -

Melanitta fusca 4 4.7 10.7 51.0 23.3 Melanitta nigra 4 3.1 9.5 40.8 17.3 Melanitta perspicillata 6 4.2 11.3 39.7 19.7 Merganetta armata 1 3.3 8.6 31.6 -

Mergellus albellus 2 2.1 9.7 32.2 -

Mergus merganser 5 1.5 14.2 43.2 24.1 Mergus octosetaceus 1 2.0 12.1 40.8 15.8 Mergus serrator 5 1.9 13.3 37.8 29.9 Neochen jubatus 4 2.5 12.8 42.7 21.6 Netta erythrophthalmica 4 2.4 9.6 41.6 31.4

continued next page Species n nV foramen nII foramen Foramen magnum Palatine angle

(mm2) (mm2) (mm2) (°) *undescribed species of Branta from the Hawaiian archipelago.

mass of Talpanas lippa . Data for Talpanas lippa are shown in bold.

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