Part 22

Proechimys leptosoma Tate, 1935, Bull. Amer. Mus. Nat. Hist., 68(5): 400; Ellerman, 1940, The families and genera of living rodents, Brit. Mus. (Nat. Hist.), 1:119.

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.

CONCLUSIONS

1. The genus Proechimys is divisible into two subgenera. In all Brazil there are four full species of each subgenus, or 8 species in all. All but one of these are divisible into subspecies of which there are 29, making a total of 30 kinds in Brazil; 14 of these are here newly named.

2. It is new information, I think, that: (1) One main fold extending entirely across the worn crown of the molariform tooth is peculiar to Trinomys; in the subgenus Proechimys, apparent complete division of the crown surface is accomplished by a short main fold meeting a counterfold originating on the opposite side of the tooth; (2) progressive decrease in size of molariform teeth from P4 to M3 is peculiar to the subgenus Trinomys; in the subgenus Proechimys, M2 is largest and the teeth are progressively smaller anteriorly.

3. In the one species, Proechimys albispinus, which has the widest distribution of aristiforms on the body of any species in the genus, some of the aristiforms are clavate. Clavate aristiforms occur in the most spiny species of the related genus Echimys.

4. In subspecies of any one full species the incisive foramen is larger in animals which inhabit arid areas than in those which inhabit humid areas. Possibly increased area of moist mucosa associated with Jacobson's organ is required in arid areas for maintenance of the necessary keenness of smell.

5. The number of counterfolds in the molariform teeth vary in clinal fashion. Their variation is in response to humidity. Increasing humidity is correlated with increasing number of folds, and decreasing humidity is correlated with decreasing number of folds.

6. Clinal variation correlated with increasing humidity is to be seen also in longer tail and darker color of pelage.

7. The primitive Proechimys probably was large, with a short tail, narrow aristiforms, strongly built skull, and five counterfolds in each molariform tooth.

8. Geographic isolation appears to have been a factor in the establishment of the two subgenera; the arid belt along the São Francisco River and northward to Ceará appears to be uninhabited by Proechimys and constitutes a barrier separating the two subgenera, Proechimys and Trinomys.

9. This arid belt probably developed relatively early, since in deposits of late Pleistocene age, remains of the subgenus Trinomys have been found in the area where the subgenus still occurs.

10. The most primitive types occur at the periphery of the range of the genus.

11. Populations from small islands tend to be more primitive than populations on the mainland. Insular populations develop a homozygous condition with resultant disappearance of secondary biotypes.

12. Insular animals ordinarily are larger than their mainland counterpart.

TABLE OF MEASUREMENTS

TABLE 1.--Measurements (in millimeters) of adults of Proechimys

Key:

A Length of head and body B Length of tail C Length of hind-foot D Length of ear from notch E Greatest length of skull F Condylo-incisive length G Zygomatic breadth H Length of nasals I Interorbital constriction J Palatilar length K Crown length of cheekteeth

====================================================================================== A B C D E F G H I J K -------------------------------------------------------------------------------------- P. g. steerei, Hyutanaham USNM 105535 218 123 48 17 53.5 44.0 25.2 19.3 11.7 18.2 8.2 USNM 105536 217 135 50 55.2 45.3 25.7 20.7 11.4 19.2 8.0 ? USNM 105537 56.3 44.9 24.0 20.4 11.4 19.3 8.7 -------------------------------------------------------------------------------------- P. g. goeldii, Fazenda Paraiso AMNH 37489 218 52 20 55.1 44.9 27.0 22.1 12.0 18.6 9.4 AMNH 37488 228 157 49 22 57.3 47.6 27.9 22.1 12.4 20.3 9.6 ====================================================================================== P. s. liminalis, Rio Quichito Mean 229 145 43 21 58.4 47.6 27.3 21.8 12.9 20.1 8.3 Maximum 250 45 24 61.7 50.0 28.9 23.0 13.8 21.2 8.8 Minimum 210 40 18 53.3 44.3 25.5 19.4 12.0 18.5 7.9 No. of specimens 5 1 5 5 5 5 5 5 5 5 5 MN 6253 215 150 43 20 57.5 46.5 28.3 21.5 12.0 19.4 8.7 MN 6250 213 42 20 60.8 49.7 22.0 13.7 21.0 9.1 -------------------------------------------------------------------------------------- P. s. amphichoricus, Esmeralda

AMNH 77000 252 163 53 60.8 50.3 27.5 24.4 13.7 20.7 9.4 AMNH 76994 260 160 54 25.5 22.8 12.6 9.5 AMNH 77020 250 181 57 62.0 52.0 27.3 25.9 13.8 21.5 9.6 AMNH 76999 235 149 50 24.0 19.0 9.3 -------------------------------------------------------------------------------------- P. s. kermiti, Lower Solimões AMNH 37124 210 55 65.2 53.7 29.2 27.6 13.5 21.4 9.0 -------------------------------------------------------------------------------------- P. l. brevicauda, João Pessoa DZ 900 245 147 48 58.3 46.6 26.5 22.5 11.6 18.2 8.2 -------------------------------------------------------------------------------------- P. l. boimensis, Boim MCZ 30881 220 160 50 54.6 44.2 24.8 21.0 11.7 17.3 7.5 MN 1976 182 140 45 52.6 42.2 24.3 20.8 11.4 16.8 7.6 Cametá MCZ 30878 240 48 55.1 45.0 25.2 22.4 11.5 18.4 7.6 -------------------------------------------------------------------------------------- P. l. longicaudatus, Urucum CNHM 26732 229 121 48 21.5 11.5 18.5 8.3 AMNH 37085 210 150 44 51.4 42.5 24.3 19.5 10.8 17.1 8.9 AMNH 37086 210 50 48.5 40.9 23.7 17.1 10.2 17.1 8.3 -------------------------------------------------------------------------------------- P. l. leucomystax, Tapirapoã AMNH 37509 230 150 43 50.7 42.2 24.5 18.4 10.3 17.5 8.1 AMNH 37510 210 42 48.1 41.3 23.0 16.9 9.9 17.2 8.1 Utiarití MN 2212 48.0 39.9 18.3 11.2 15.9 8.0 Salto Sepotuba MN 1936 202 147 44 52.6 43.0 23.6 19.2 10.7 17.8 7.8 -------------------------------------------------------------------------------------- P. l. roberti, Anapolis Mean 208 159 45 21 52.7 43.5 24.9 20.7 13.1 17.2 7.9 Maximum 235 190 55 25 56.1 47.8 27.1 23.7 12.0 19.1 8.2 Minimum 170 135 36 18 48.1 40.0 22.8 18.2 10.6 15.6 7.6 No. of specimens 16 14 16 16 11 11 11 11 11 11 11 Mean 219 149 44 20 51.1 42.3 24.1 20.0 10.7 17.2 8.0 Maximum 290 155 48 24 55.5 45.4 25.8 21.5 11.1 17.7 8.7 Minimum 195 125 40 18 48.9 40.3 23.1 19.1 10.5 16.6 7.7 No. of specimens 10 8 10 10 7 7 7 7 7 7 7 ====================================================================================== P. g. villicauda, Tapirapoã MN 1932 225 145 47 55.6 45.5 26.8 24.0 12.0 18.1 8.9 MN 1934 215 162 50 56.2 46.0 26.1 21.3 12.0 18.6 8.4 Utiarití AMNH 57544 250 200 55 . 24.3 13.1 19.9 9.1 -------------------------------------------------------------------------------------- P. g. ribeiroi, Rio 12 de Outubro MN 1935 190 134 47 50.1 41.0 24.3 20.0 11.5 15.9 8.1 -------------------------------------------------------------------------------------- P. g. hyleae, Tauarí Mean 248 146 52 58.1 47.6 27.1 22.9 12.1 19.4 8.5 Maximum 260 174 53 59.0 47.8 . 23.4 13.2 20.0 8.8 Minimum 217 143 51 57.2 46.5 . 22.4 11.1 18.8 8.3 No. of specimens 4 3 4 2 2 1 2 2 2 2 Mean 229 149 50 54.3 44.9 25.8 21.0 11.8 18.1 8.5 Maximum 270 168 54 56.1 46.3 27.4 23.0 13.4 19.3 9.0 Minimum 190 132 49 51.5 42.9 24.5 19.1 11.1 17.1 7.9 No. of specimens 10 9 10 9 11 11 10 10 10 10 -------------------------------------------------------------------------------------- P. g. nesiotes, Ilha de Manapirí CNHM 19496 201 133 47 20 52.7 42.7 25.1 19.5 11.1 17.8 8.0 MN 1975 200 152 47 21 52.1 42.6 25.8 19.5 12.3 18.3 8.0 -------------------------------------------------------------------------------------- P. g. leioprimna, Cametá AMNH 37484 192 151 41 22 54.8 44.9 25.4 19.2 12.6 18.4 8.4 CNHM 19503 189 164 47 22 54.4 43.7 26.2 20.5 12.6 18.2 8.2 CNHM 19536 189 43 22 -------------------------------------------------------------------------------------- P. g. oris, Providencia CNHM 19495 230 170 45 24 56.1 47.1 25.8 22.0 11.4 17.4 8.3 Tanaquará MN 1974 230 175 49 23 53.2 43.0 23.8 20.1 10.5 17.9 7.7 Rio Guamá AMNH 37487 205 142 42 21 -------------------------------------------------------------------------------------- P. g. arescens, Fazenda Inhuma CNHM 26440 206 149 51 24 54.7 44.1 26.3 21.4 12.1 18.7 8.3 CNHM 26441 191 164 51 55.6 45.0 25.7 22.4 11.7 18.7 8.7 -------------------------------------------------------------------------------------- P. g. riparum, Manaus AMNH 143018 225 44 20 52.6 43.2 24.0 20.5 11.0 17.2 6.7 -------------------------------------------------------------------------------------- P. g. arabupu, Arabupu AMNH 75816 243 220 56 59.2 48.7 27.0 23.8 12.9 17.8 8.7 AMNH 75819 230 181 52 55.0 46.0 26.0 22.5 12.3 16.9 8.3 AMNH 75815 228 198 52 AMNH 75810 226 170 48 53.9 45.6 25.6 21.0 12.0 16.1 8.3 AMNH 75823 209 188 48 53.4 43.9 24.5 21.5 11.7 16.4 8.3 AMNH 75817 204 167 47 51.1 43.1 . 21.6 11.3 16.6 8.2 -------------------------------------------------------------------------------------- P. dimidiatus, Pedra Branca Mean 199 170 46 52.4 43.5 26.2 19.5 12.1 16.4 8.3 Maximum 220 195 50 56.4 47.1 27.5 21.5 13.6 18.0 8.7 Minimum 180 150 44 48.1 40.4 24.6 17.5 11.0 14.4 7.4 No. of specimens 19 18 19 45 46 45 45 46 46 46 Mean 197 162 44 51.8 42.9 25.8 19.4 11.8 16.3 8.3 Maximum 230 180 46 55.1 45.9 27.4 22.0 13.0 18.4 8.9 Minimum 165 145 42 48.6 39.5 23.8 17.6 10.7 14.8 7.7 No. of specimens 14 12 14 42 44 44 42 44 44 44 -------------------------------------------------------------------------------------- P. i. iheringi, Ilha de São Sebastião Mean 207 197 48 54.5 44.6 26.2 19.9 12.0 18.3 8.3 Maximum 220 205 50 55.0 45.2 27.1 20.4 12.8 18.7 8.5 Minimum 196 190 46 53.5 43.7 25.9 19.3 10.9 17.5 8.0 No. of specimens 5 2 5 5 5 4 4 5 5 5 MN 6453 228 185 46 54.3 44.5 25.9 20.5 11.0 18.9 8.2 DZ 2095 205 180 46 53.2 42.9 26.4 18.9 11.1 17.0 8.2 DZ 2525 205 46 56.9 45.8 27.8 20.9 12.5 18.9 8.2 -------------------------------------------------------------------------------------- P. i. bonafidei, Fazenda Bõa Fé Mean 211 186 50 25 53.3 43.4 25.6 20.2 12.1 16.3 8.5 Maximum 220 194 54 26 55.8 45.2 26.3 21.7 13.2 17.4 9.1 Minimum 200 176 47 24 50.7 41.0 24.2 19.1 11.0 14.8 8.1 No. of specimens 7 5 8 8 4 5 5 7 7 7 7 Mean 209 185 52 25 52.6 44.4 26.6 20.0 12.4 16.4 8.6 Maximum 226 203 55 27 56.9 46.4 28.6 21.4 13.2 17.0 9.2 Minimum 185 153 50 22 44.4 42.3 24.9 18.0 11.4 15.5 8.2 No. of specimens 7 7 7 7 6 6 7 7 7 7 7 -------------------------------------------------------------------------------------- P. i. gratiosus, Floresta da Caixa Dagua Mean 193 191 48 51.2 41.4 25.5 18.5 11.7 16.3 8.0 Maximum 200 200 49 51.7 42.2 27.0 18.9 12.0 16.7 8.2 Minimum 185 175 47 50.5 40.4 24.6 18.0 11.1 15.6 7.9 No. of specimens 5 5 5 5 5 5 5 5 5 5 Mean 204 175 49 24 50.5 42.1 26.0 18.4 11.4 16.3 7.9 Maximum 220 190 50 26 52.6 43.1 26.6 19.5 12.1 17.5 8.2 Minimum 195 160 47 22 48.4 41.0 25.3 17.5 10.7 15.3 7.6 No. of specimens 5 2 5 4 4 4 4 4 4 4 4 -------------------------------------------------------------------------------------- P. i. paratus, Floresta da Capela de São Braz MN 4023 203 195 54 28 51.2 41.7 25.4 18.3 10.4 16.2 8.4 MN 5458 190 170 51 27 MN 4012 220 210 54 29 52.2 42.3 25.4 19.1 12.3 17.5 8.7 -------------------------------------------------------------------------------------- P. i. panema, Campinho MN 8286 215 45 23 54.0 45.1 27.7 19.5 13.4 16.4 8.1 MN 8284 195 180 43 23 51.5 41.8 24.5 18.1 11.4 16.0 7.6 MN 8288 190 190 46 21 51.6 42.8 25.3 18.1 11.7 15.7 7.9 MN 8287 200 190 46 23 52.6 43.6 27.2 18.4 12.5 16.7 8.3 MN 8285 190 45 24 50.0 41.1 26.6 19.4 12.3 16.1 8.1 -------------------------------------------------------------------------------------- P. i. denigratus, Mata do Ribeirão da Fortuna Mean 197 218 52 24 51.5 42.2 25.7 18.3 11.3 16.0 8.2 Maximum 217 242 54 28 55.4 45.3 27.0 20.3 12.4 17.6 8.5 Minimum 190 204 50 21 48.7 39.5 23.7 16.8 10.4 15.0 8.0 No. of specimens 10 9 9 10 8 8 8 8 8 8 8 Mean 201 207 52 24 49.1 41.2 25.0 18.3 11.2 16.0 7.8 Maximum 225 225 54 28 54.1 44.6 25.7 21.5 11.8 17.1 8.3 Minimum 180 175 49 20 48.2 39.5 23.5 17.4 10.5 15.5 7.5 No. of specimens 12 12 12 12 8 8 8 8 8 8 7 -------------------------------------------------------------------------------------- P. s. setosus, ? No locality AMNH 16140 39.8 25.2 11.0 15.9 7.6 -------------------------------------------------------------------------------------- P. s. elegans, Lagoa Santa UZM H82 190 190 47 25 24.3 17.5 11.2 16.6 7.7 ? UZM L104 48.6 40.8 24.8 16.6 10.3 15.9 7.7 ====================================================================================== P. a. albispinus, Macaco Seco Mean 175 162 40 45.9 39.7 23.6 15.6 10.6 15.7 7.6 Maximum 193 173 47 48.2 42.0 24.9 17.1 11.6 17.5 8.2 Minimum 165 147 38 44.2 38.1 22.7 14.8 9.7 14.3 7.2 No. of specimens 9 8 9 11 12 12 14 13 14 13 CNHM 20402 187 171 40 46.0 40.8 23.8 14.9 11.3 16.0 7.4 CNHM 20408 47.6 40.7 24.6 17.1 11.2 15.9 8.2 -------------------------------------------------------------------------------------- P. a. sertonius, Lamarão CNHM 18196 190 160 36 25 11.7 Bonfim MN 6454 185 175 37 45.7 39.8 24.2 15.5 10.7 16.1 7.5 DZ 2636 190 150 35 43.8 37.6 22.8 14.7 9.6 14.5 DZ 2635 175 155 38 46.7 40.6 23.3 16.9 10.2 15.1 7.4 --------------------------------------------------------------------------------------

LITERATURE CITED

ALLEN, J. A. 1904. Mammals from the District of Santa Marta, Colombia, collected by Mr. Herbert H. Smith, with field notes by Mr. Smith. Bull. Amer. Mus. Nat. Hist., 20:407-468, November 28, 1904.

1916. Mammals collected on the Roosevelt Brazilian Expedition, with field notes by Leo E. Miller. Bull. Amer. Mus. Nat. Hist., 35:559-610, August 9, 1916.