Hydromys chrysogaster E. Geoffroy 1804

Hydromys chrysogaster E. Geoffroy 1804, Bull. Sci. Soc. Philom. Paris, 93: 354.

Type Locality: Australia, Tasmania, Bruny Isl (see Mahoney and Richardson, 1988:157).

Vernacular Names: Common Water Rat.

Synonyms: Hydromys apicalis Kuhl 1820; Hydromys beccarii Peters 1874; Hydromys caurinus Thomas 1909; Hydromys esox Thomas 1906; Hydromys fuliginosus Gould 1853; Hydromys fulvogaster Jourdan 1837; Hydromys fulvolavatus Gould 1853; Hydromys fulvoventer Cuvier 1837; Hydromys grootensis Troughton 1935; Hydromys illuteus Thomas 1922; Hydromys lawnensis Troughton 1935; Hydromys leucogaster Geoffroy 1804; Hydromys longmani Thomas 1923; Hydromys lutrilla Gould 1853; Hydromys melicertes Thomas 1921; Hydromys moae Troughton 1935; Hydromys nauticus Thomas 1921; Hydromys oriens Troughton 1937; Hydromys reginae Thomas and Dollman 1909 .

Distribution: Australia: freshwater lakes and rivers as well as swamp, salt marsh, and supralittoral habitats (absent from C Australian region); also found on Tasmania and numerous smaller islands off the coast of Australia (Friend and Thomas, 1990; Robinson et al., 2000; Rounsevell et al., 1991; Seebeck, 1995 b; Watts and Aslin, 1981:67); Kai Isls and Aru Isls. New Guinea: throughout most of the island from sea level to 1900 m (Flannery, 1990 b:188; 1995 a:237;). Also on the Melanesian and Wallacean islands of Goodenough, Yapen, Biak, Kiriwina, Fergusson, Normanby, and Obi (Flannery, 1995 b).

Conservation: IUCN – Lower Risk (lc).

Discussion: Chromosomal data presented by Baverstock et al. (1977 c, 1983 b). Morphology of spermatozoa and male reproductive tract discussed in context of comparative study of Australian murines (Breed, 1984, 1986; Breed and Sarafis, 1978; Morrissey and Breed, 1982). References to distributional, taxonomic, and biological literature for Australia cataloged by Mahoney and Richardson (1988:156). Significance of variation in body size and pelage color needs to be assessed in context of careful systematic revision of the species; more than one species likely exists among available samples (the single specimen from Obi Isl, for example, likely represents a separate species, as does a very small-bodied specimen from highland oak forest on Goodenough Isl, which may be a montane endemic distinct from H. chrysogaster in the lowlands; K. Helgen, in litt., 2003). Australian population reviewed by Olsen (1995), New Guinea by Flannery (1995 a). Leary and Seri (1997) reported specimens from Mt Sisa in Papua New Guinea. Aplin et al. (1999) reported a specimen of this species from a Holocene archaeological site on the Ayamaru Plateau, central Bird’s Head Peninsula of West Papua.