Microryzomys Thomas 1917

Microryzomys Thomas 1917, Smithson. Misc. Coll., 68: 1.

Type Species: Hesperomys minutus Tomes 1860

Synonyms: Thallomyscus Thomas 1926 .

Species and subspecies: 2 species:

Species Microryzomys altissimus Osgood 1933

Species Microryzomys minutus (Tomes 1860)

Discussion: Oryzomyini . Named as a subgenus of Oryzomys and either retained as such (Cabrera, 1961; Ellerman, 1941; Osgood, 1933 a) or placed in synonymy with Oligoryzomys (Gyldenstolpe, 1932; Tate, 1932 e; Thomas, 1926). Junior synonymy of Thallomyscus established by Osgood (1933 a). Raised to genus by Carleton and Musser (1984) and later revised by them (1989). Cladistically primitive member of Oryzomyini, sharing certain morphological traits with Oligoryzomys (Carleton and Musser, 1989; Carleton and Olson, 1999); sister genus to Neacomys according to gene sequence studies (Myers et al., 1995; Patton and da Silva, 1995; Smith and Patton, 1999) or to the Neacomys Oligoryzomys clade according to allozymic analyses (Dickerman and Yates, 1995).