Southern groove-toothed moss mouse

The southern groove-toothed moss mouse (Microhydromys argenteus) is a species of rodent in the family Muridae found in southern Papua New Guinea. Until 2010 its specimens were referred to Microhydromys richardsoni, from which it is distinguished mainly by its gray-brown fur. It is a tiny murine, with a head and body of 78 to 86 mm, a tail of 71 to 83 mm and a weight of 12 to 13 g, with short velvety fur, very reduced eyes, long fine whiskers and grooved upper incisors. It is known from only three localities in the southern foothills of the Central Cordillera of eastern New Guinea, in forest between about 380 and 1450 m: secondary forest and eucalypt savanna on the Sogeri Plateau, primary hill forest on limestone karst on the Darai Plateau, and lower montane forest at Mount Sisa. Its body proportions and small eyes suggest a terrestrial, nocturnal and possibly semi-fossorial way of life. It appears to be nowhere common and is classified as Data Deficient.