MAMMALIAN SPECIES No. 187, pp. 1-8, 4 figs. Macropus giganteus. By W. E. Poole Published 23 November 1982 by The American Society of Mammalogists Macropus giganteus Shaw, 1790 phenotype A may be distinguished from populations of west ern grey kangaroos with individuals carrying any one of three trans- Eastern Grey Kangaroo ferrin phenotypes A, AB or B. M. giganteus and M. fuliginosus are immunologically distinct and possess characteristic antigens. Macropus giganteus Shaw, 1790:p1. 33 and text. Type locality Cooktown, Queensland. Generally regarded as a junior sec- GENERAL CHARACTERS. Macropus giganteus is a large Downloaded from https://academic.oup.com/mspecies/article/doi/10.2307/3504005/2600565 by guest on 27 September 2021 ondary homonym of [aculus giganteus Erxleben, until Shaw's kangaroo with soft fur, relatively uniform light to dark grey pelage name was validated under the plenary powers of the Inter- which is somewhat paler ventrally and has darker vertebral shad- national Commission on Zoological Nomenclature (Opinion ing; the fore and hind digits and distal third of the tail tend to be 760, Bull. Zoo1. Nomencl., 1966, 22:292-295) as the type dark brown or black (Fig. 1). Th e pelage varies in length and species, by monotypy, of the genus Macropus . density with locality and season. Animals from north Queensland Kanguroo gigas Lacepede, 1799:6. Name used in taxonomic have short coats whereas those from the southern highlands and grouping based on numbers of teeth. Tasmania have longer, more dense and woolly fur. There is marked Macropus major Shaw , 1800:505. Type locality Sydney, New South sexual dimorphism in size ; male s attain a larger size than females Wales, as restricted by lredale and Troughton (1934). and with maturity, become more heavily developed in head , ches t Dipus tridactylus Perry, 1811:pl. 63 and text. Type locality New and forelimbs. Maximum weights recorded reach 90 kg for males South Wales. and 40 kg for females. Kangurus labiatus Desmarest, 1817:33. Type locality, vicinity of Young kangaroos grow rapidly for about 2 years, then growth Botany Bay and Port Jackson, County of Cumberland, New slows considerably (Poole, pers. observ .). The range of external South Wales. measurements (mm) taken at regular intervals from anaesthetised captive-bred males aged 2 to 7 years and females aged 2 to 8.5 A number of variant generic assignments and spellings of years are as follows: total length, males 1,500 to 2,000, females canguru, a dubious name rejected by Opinion 760, and of gigan- 1,500 to 1,800; length of head, 170 to 220 and 165 to 190; length teus, are omitted from the synonymies. of ear, 115 to 130 for both sexes; length of forearm (outside di- CONTEXT AND CONTENT. Order Diprotodonta, Family mension, elbow to wrist with the bones forming the joints placed Macropodidae, Subfamily Macropodinae. Opinions regarding the at right angle s), 180 to 300 and 170 to 230; length of tibia (outside generic limits of the genus Macropus have been diverse. As in- dimension, knee to sole of hind foot with the bones forming the dicated by Bartholomai (1975), species referrable to Macropus joints placed at right angles), 450 to 580 and 440 to 530; length have been relegated by interpretation of individual taxonomists of hindfoot, 310 to 347 and 300 to 320; length of tail (ventral to at least 20 additional genera or subgenera. Current usage ac- surface from butt to tip), 750 to 1,000 and 700 to 840; weight 25 cepts some 14 extant species of kangaroos and wallabies within the genus Macropus (Calaby, 1971; Kirsch and Calaby, 1977; Poole, 1979; Ride, 1970). Among these is the western grey kan- garoo Macropus fuliginosus (Desmarest), a species closely related to Macropus giganteus Shaw (see Kirsch and Poole, 1972). With additional research, three subspecies may be recognized (Kirsch and Poole, 1972), as follows: M. g. giganteus Shaw, 1790:p1. 33 and text, see above (gigas Lacepede a synonym). Neotype, Queensland Museum spec- imen 110749, collected at King's Plains 32 km south of Cook- town, Queensland; designated by Calaby et a1. (1962) and restated by Calaby and Ride (1964). M. g. major Shaw, 1800:505, see above itridactylus Perry and labiatus Desmarest are synonyms). Name validated under the plenary powers of the International Commission on Zoo- logical Nomenclature, Opinion 760. M. g. tasmaniensis Le Souef, 1923:145. Type locality Tasmania. DIAGNOSIS. Along with the red kangaroo, Macropus rufus, and the hill kangaroos, Macropus robustus, grey kangaroos are among the largest living marsupials. For almost two centuries after their discovery, disagreement over their taxonomic status was provoked by the morphological variation recorded throughout their considerable geographic range. Early accounts frequently confused the localities of origin of grey kangaroos and subsequent writings incorporated composite descriptions of the varied morphs (e.g. Thomas, 1888; Troughton, 1967; Wood Jones, 1924). Distinctive features of all grey kangroos are the hairy muzzle with fine hairs appearing between the nostrils, down nearly to the upper lip, leaving only the margins of the nostrils ringed with naked black skin (Frith and Calaby, 1969; Thomas, 1888; Wood Jones, 1924), the characteristic shape of the zygoma (Wood Jones, 1924), and the strongly double-grooved third incisor with a width equal to, or greater than, the combined width of the first and second incisors (Frith and Calaby, 1969; Thomas, 1888; Wood Jones, 1924). Recent studies (Kirsch and Poole, 1972) have supported a primary division of grey kangaroos into two species, the light to dark grey colored M. giganteus and the brown M. fuliginosus , FIGURE 1. External view of Macropus giganteus in forest habi- Populations of eastern grey kangaroos with a single transferrin tat, south coast New South Wales. Photograph by E. C. Slater. 2 MAMMALI AN SPEC IES 187 Tasmani a by Wap stra (1976). Live trappin g and relocat ion of east- ern grey kan gar oos have been und ertak en in Tasmania with 45 animals introduced to Mari a Island in 1969-70 and 1,500 released at 18 sites in the southe rn half of th eir historic ran ge since 1971 (Pearse, per s. comm.; Wap stra, 1976). FOSSIL RECORD. M. giganteus has been record ed from Pleisto cen e deposits in southeast Queensland at Gore (Bartho- M.g.giganteus lomai, 1977), Tex as (Archer, 1978), and from southwes te rn New --(Cooktown) South Wale s, in th e region of Lake Victoria (Mars hall, 1973). ---') Because M. giganteus has affinities with a larger, older foss il form (Mac ropus titan Owen , 1838), it was regard ed as a successional spec ies of th e latter by Bartholoma i (1975). He ant icipated tha t with an improved fossil record it would be difficult to se parate Downloaded from https://academic.oup.com/mspecies/article/doi/10.2307/3504005/2600565 by guest on 27 September 2021 the two taxa. Marshall (1973) sugges ted that spec ies such as M. titan, present in the late Pleisto cen e se dime nts, represent ed a I 30% lar ger an cestral form of M. giganteus, which may have been subject to ' pos t-pleis tocene dwarfing' . Because the two form s oc- ,I Qld cur in th e same depo sits in southeast Qu een sland, Arch er (1978) doubted this interpret ation. There is deb at e about conte mpor- r--_l an eit y of th e two form s du e to the complex stratigraphic history --7 of the Qu een sland deposits. Add itionally, it is possible that some , of the specimens regarded as M. giganteus may represent small individuals of M. titan, or they may represent the morphologically b-- similar M. fuliginosus, not yet formally record ed in Qu eensland S.A . -. but pr esent in western New South Wal es (Arc her, 1978). I FORM. The gen er al color of th e pelage varies in inten sit y I from light silver grey to dark grey and may exhibit brownish over- N.SW. tones on back and flanks. Th e pelage along the mid-dorsal line is ofte n dark, freque ntly giving the imp ression of a dorsal stripe. L Th e fur is short or long depending on climate. It is soft and den se Q • M..q.meior and in mountainous and southern regions may be thi ck and wool- i ''"'', ly. Below th e lower thorax th e hair on the mid-dorsal line lies I \ (Sydney) ~Vic. '" with th e tip s point ing posteriorly. Anterior to th e lower thorax the hair point s forward, reversin g direction again from level with th e eyes to the tip of th e nose. Th e hair on th e nose is short and fine, there being bare skin only around th e edge of the nostrils. Th e iris is dark brown and the eyelash es long an d dark brown to black in color. Vihri ssae are well develop ed , brown to black in color, and incl ude mystacial , suprao rbital, gen al, subme ntal, int erra- mal , and med ial antebrachial. The skin of th e ea rs is darkly pig- ment ed; the hair on th e dorsa l surface is of si milar color or per- haps darker than th at on th e dorsal surface of the body, whereas that on the ventral surface is sparse and white. Many hair s on th e head, body, and tail bea r distin ct pal e bands; those on the face, throat , arms, belly, legs, and tail are gene rally pale, but FIGURE 2. The geographic range and typ e locality of Macropu s those on th e finger s, toes, and tail dark en towards the tip.