The 100 Days Project: Day 54 
The Major Roos:
Photo: Macropus robustus, Canberra Nature Map (CC BY 3.0 AU)
Do a little Google-hopping and you’ll find numerous sites telling you ‘wallaroo’ is a combination of ‘kangaroo’ and ‘wallaby’. It makes sense, after all. With the exception of the diminutive Barrow Island wallaroos, about half the size of their mainland cousins, wallaroos do sit between the larger Red and Grey kangaroos and the smaller wallabies. But the word in fact comes from ‘walaru’, from the Dharug language of what we might now call the Sydney basin. And if I’ve made it sound as if the wallaroos are significantly smaller than, say, the Reds or Eastern Greys, I’ve misled you. Macropus robustus is just that, robust, and only marginally smaller. It’s not all that unusual to find a male nearly two metres tall.
If we think of kangaroos as creatures of the plains and open grass- and wood-lands, and the more chunky, thick-set, upright-hopping, smaller-footed wallaroos as creatures of, in the east, the Great Dividing Range and adjacent highlands and, moving westward, of rocky slopes and ancient, eroded mountainscapes, you are beginning to get it – creatures adapted to negotiating, with remarkable agility (and hiding within), raised places, lovers of heights and caves. They are also called the Hill kangaroos.
Fortunately, flat as Australia is, such hill-places are to be found throughout the country, and, although their characteristic landscapes make them less visible, the wallaroos have the widest distribution of all the major roos. By and large, they are called wallaroos in the east, and euros in the west, although technically this is a category confusion. The wallaroo is the species; euros are a sub-species of that species.
Euro. The term has nothing to do with the European currency, indeed nothing to do with Europeans at all. It’s not even, as some have guessed, an adaptation from the Latin name of that subspecies. (The species is Macropus robustus; the Euro subspecies is Macropus robustus erubescens, which means ‘with a ruddy nape’. Euro males are distinguished by a reddish-brown nape.) The term ‘euro’ actually comes, according to the Oxford English Dictionary, from the word ‘yuru’ in the Adnyamathanha language of the Flinders Ranges in South Australia.
From one perspective, there are two species of wallaroo, the ‘Common’ wallaroo (Macropus robustus) and the singular and slightly mysterious Black wallaroo (Macropus bernardus). There are four currently-recognised sub-species of the Common wallaroo: the Eastern wallaroo (Macropus robustus robustus), the Euro, the diminutive Barrow Island wallaroo (Macropus robustus isabellinus), and the Northern wallaroo (Macropus robustus woodwardi) of Arnhem Land and the Kimberly. There are no subspecies of the Black wallaroo, a species notoriously difficult to track down in the wild, from their shyness and the inaccessibility of their habitual terrain.
If you’re ever in the situation of having to tell the four subspecies of the Common wallaroo apart (an unlikely line-up!), here are a few tips. First, check their noses to make sure they are wallaroos (anyone with a hairy rhinarium is out). The smallest in this line-up would be the Barrow Island wallaroo. Of the two largest of the others, the one with the large ears (and perhaps ruddy nape) would be the Euro, the one with the small ears the Eastern wallaroo. The last (a process of elimination) would be the Northern, who in other respects is a bit harder to identify.
I have said above that ‘from one perspective’ there are two species of wallaroo. Sometimes a third, the Antilopine wallaroo, is listed. But there is some taxonomic uncertainty here. The Antilopines are also listed as kangaroos. I’ll discuss their curious predicament in a coming post.
The nose isn’t the only thing to keep in mind when you’re trying to tell wallaroo from kangaroo. There’s an angle in the hop, for example, and a stance. The other major macropods lean into their bound, to reduce air resistance, as befits creatures of more level landscapes. Wallaroos, when hopping, are more upright, as befits climbers, their wrists, when stationary, characteristically raised, their elbows held in close to the body, their shoulders thrown proudly back.