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Emperor Giant Rat

Uromys imperator

French: Uromys empereur / German: Kaiserriesenratte / Spanish: Rata gigante emperador

Other common names: Emperor Rat, Emperor Uromys

Taxonomy. Mus imperator Thomas, 1888,

“Aola, Guadalcanar [= Guadalcanal Island] ... Solomon Islands. ”

Within Uromys, U. imperator is included in subgenus Cyromys along with the other two Guadalcanal species, namely U. porculus and U. rex. Monotypic.

Distribution. Guadalcanal I, Solomon Is.

Descriptive notes. Head-body 340-350 mm, tail 250-258 mm, ear 19-20 mm, hindfoot 64-66 mm. No specific data are available for body weight. The Emperor Giant Ratis a very large species of Uromys similar to the King Giant Rat (U. rex), from which it is distinguished by its shorter tail and its larger size. Pelage is short and woolly to the touch but looks wiry. Dorsal pelage is dark grizzled ash gray, and ventral pelage is white. Feet are broad and naked. Ears are short and silvery pink; vibrissae are long, and black or white. Tail is relatively long (73% of head-body length) and blackish brown. Skull is similarto that of the King Giant Rat, but not so deep. There are two pairs of mammae, both inguinal.

Habitat. Found near the coast in the dry northern lowlands of the island, but it has been suggested that it has been restricted to mossy montane forests.

Food and Feeding. No information.

Breeding. No information.

Activity patterns. No information.

Movements, Home range and Social organization. No information.

Status and Conservation. Classified as Critically Endangered (Possibly Extinct) on The [UCN Red List. The Emperor Giant Rat is known only from the three original specimens collected between 1886 and 1888, and is possibly extinct. Another specimen exists just as a skin and may represent this species, but it may also represent the King Giant Rat. Although the exact reason for the Emperor Giant Rat’s decline and possible extinction is unknown, overhunting and loss of suitable habitat, or competition, predation, and disease transmission from introduced species may have played varying roles in it. Terrestrial habits may have been the downfall of the species, in contrast to the more recently seen King Giant Rat. Further surveys are needed in order to confirm its continued existence on the island.

Bibliography. Bryant et al. (2011), Flannery (1995a), Groves & Flannery (1994), Helgen, Leary & Wright (2016a), Lavery (2014), Musser & Carleton (2005), Steppan & Schenk (2017).