Unlike humans, the swamp wallaby has seven carpal bones, not eight (the scaphoid and lunate form a single scapholunar bone). The trapezoid is tiny (5 mm long)
mccready @ brisnet . org . au (take spaces out)
Wallabia bicolor carpal tunnel.JPG Wallabia bicolor overview.JPG
Wallabia bicolor carpals apr 2006.JPG Wallabia bicolor carpals in order.JPG
Wallabia bicolor ulna tip in triquetral.JPG Wallabia bicolor scapholunar still bound.JPG
Wallabia bicolor joint capsule scapholunar hamate 2.JPG Wallabia bicolor joint capsule scapholunar hamate.JPG
Wallabia bicolor left scapholunars.JPG Wallabia bicolor two left scapholunars.JPG
Wallabia bicolor triquetrals.JPG Wallabia bicolor trapeziums.JPG
Wallabia bicolor trapeziums 2.JPG Wallabia bicolor trapezoid.JPG
Wallabia bicolor left trapezoids.JPG Wallabia bicolor left capitates.JPG
Wallabia bicolor capitate and trapezoid separating.JPG Wallabia bicolor capitates.jpg
Wallabia bicolor left hamates.JPG Wallabia bicolor hamate separating.JPG
Wallabia bicolor distal carpal row hamate on left.JPG
Wallabia bicolor distal row without hamate.JPG Wallabia bicolor second carpal row.JPG
Wallabia bicolor distal row stepped metacarpals.JPG miscellaneous bones t.jpg
Mnemonic for wrist bones of mammals and their order in the two carpal rows:
Sally Left The Party, To Take Cathy Home
(1st, upper, medial, proximal row = scaphoid, lunate aka semi-lunar, triquetral aka cuneiform, pisiform)
(2nd , lower, distal row = trapezium, trapezoid, capitate aka os magnum, hamate aka unciform hook shaped)
Swamp Wallaby is in Class Mammalia, Subclass Marsupialia (Metharians also include Marsupials), Order Diprotodontia (Koalas, Wombats, Possums, Macropods), Superfamily Macropodoidea, Family Macropodidae (Wallabies, kangaroos, tree-kangaroos), Subfamily Macropodinae, Genus Wallabia, Species bicolor. This classification is from: Mammals of Australia, Editor Ronald Strahan, revised edition, Reed New Holland Publishers, Sydney, 1995, which says “A combination of genetic, reproductive, dental and behavioural characteristics set the Swamp Wallaby so far apart from other wallabies that it is classified as the sole living member of the genus Wallabia.” p409. This is debated because it can hybridize with Macropus agilis (agile wallaby) so perhaps should be placed in the genus Macropus.