Jo?o Moojen

Loncheres myosuros Lichtenstein, 1818, Das zoologische Museum der UniversitÄt zu Berlin, (2):18 (nomen nudum); Lichtenstein, 1820, Abhandl. K. Akad. Wissensch., Berlin (1818-1819):192, pl. 1, fig. 2 (orig. descr.); Wied, 1826, BeitrÄge zur Naturgeschichte von Brasilien, 2:445.

General characters.—Aristiforms wide (1''') and numerous on dorsal parts of body; tail longer (9") than head and body (8"); hind feet short (1"6''').

Color (According to Lichtenstein and Brants' descriptions).—Black between ears; dark brown on middorsal line with reddish tinge on front and upper side of neck; posteriorly from shoulders there is a greasy shine added to color; this dark, dorsal band widens posteriorly, there encroaching on sides of body; sides lighter brown, sparsely marked with dark brown lines, from sides of head caudad to, and including, outer surfaces of hind legs; outer sides of forelegs colored like outer sides of hind legs; ankles ringed with brown. Tail blackish above, whitish below. Upper surfaces of hands and feet white.

Skull.—No description of skull or teeth found.

Remarks.—Thomas (1921:140-143) summarized the available information on the forms from southeastern Brazil and synonymised myosuros with setosus. The description of leptosoma by Brants applies to this same species except in a few features. However, neither Brants nor Lichtenstein described the tail of myosuros as having a white tip or even as having a heavily pencilled tip, although Wagner (1843:342) in redescribing Lichtenstein's species indicated that the tail had a white pencil. He gave also measurements of the head and body, and tail, which do not agree with the original measurements given by either Lichtenstein or Brants. Lichtenstein, in the original description, gave the type locality of myosuros as Bahia, and stated that it was collected by Freireiss. Brants also gave Bahia as the type locality for leptosoma. The names leptosoma Brants and cinnamoneus Lichtenstein are evidently no more than duplicate names for myosuros, as pointed out by Thomas (1921:141) and subsequent writers. Specimens referred to any of these forms, therefore, could take the earlier name myosuros until identified otherwise. Lichtenstein later (1830, text for plate 36, fig. 2) added SÃo Paulo State to the known range of the species, mentioning specimens collected there by Sello. Probably, therefore, Wagner redescribed leptosoma using a composite sample; the white tip on the tail could occur in any race of P. iheringi from SÃo Paulo.

Considering the short hind feet and the wide aristiforms, Proechimys myosuros probably will eventually prove to be related to albispinus; perhaps it will prove to be a synonym of albispinus.