López-Torres and Silcox—European Paromomyidae
923
Figure 2.
1915, USGS 21712, right; (2) Paromomys depressidens Gidley, 1923, USNM 9677; (3) Edworthia lerbekmoi Fox et al., 2010, UALVP 50990, right; (4) Ignacius frugivorus Matthew and Granger, 1921, YPM-PU 20690, left; (5) Acidomomys hebeticus Bloch et al., 2002, UM 108206, left; (6) Arcius fuscus Russell et al., 1967,MU 6507, left; (7) Arcius lapparenti Russell et al., 1967, AV 5849, left; (8) Arcius zbyszewskii Estravís, 2000, SV3-47, left; (9) Arcius hookeri n. sp., BMNH.M 44945, right. The paromomyids on the top row (1–5) have an invagination at the top central area of the hypoconulid lobe; all Arcius species (6–9) lack this feature. Scale bar=1mm.
Distal view of micro-CT scan images of the M3 of various species of North American and European paromomyids. (1) Phenacolemur citatus Matthew,
(Rose, 1981; Silcox et al., 2008) and Acidomomys (Bloch et al., 2002). This might suggest that Arcius underwent a process of retention of a deciduous P4. Arcius rougieri shows a possible retention of the deciduous upper central incisor (see the following). Based on the two most complete specimens that belong to
the genus Arcius, PAT1 and PAT2, the dental formula for this genus would be 2:1:2:3
masses for all the species in the genus.
Arcius rougieri Godinot, 1984 Figures 1, 5
1981 Arcius cf. A. fuscus Godinot, 1981, p. 77. 1984 Arcius rougieri Godinot, 1984, p. 85. 1991 ?Arcius rougieri; Marandat, 1991, p. 92.
2003 Arcius rougieri; Aumont, 2003, pl. 3, fig. 5, pl. 6, fig, 5, 6. Pl. 18, fig. 1, pl. 19, 23.
Holotype.—PAT1, partial maxilla with right I1–C and left I1–M1.
Emended diagnosis (modified from Godinot, 1984).—Smaller M2 than Arcius lapparenti, A. hookeri n. sp., and A. ilerdensis n. sp., but larger M1 than A. zbyszewskii. Further differs from A. fuscus and A. lapparenti in having a more apically extended (taller) anterocone than mediocone on I1, with a significantly smaller posterocone, and laterocone proximally shifted relative to the anterocone. Further differs from all other species of Arcius in having a more buccally extended parastylar region onM1 and a stepped postvallid on M1 and M2. Further differs from A. fuscus in having a more distally expanded distolingual basin
1:0:1:3. See also Table 1 for estimated body
on M3. Further differs from A. fuscus in having two crests, instead of three, on the P4 postvallid. Paraconid of M1 is smaller than in A. fuscus and A. lapparenti but larger than in A. zbyszewskii. Mesial inflection ofM1 andM2 trigonids weaker than in A. ilerdensis n. sp. but stronger than in the other known species of Arcius. Further differs from A. zbyszewskii and A. ilerdensis n. sp. in having a cingulid on the buccal half of the distal aspect of M1 that runs up to the hypoconulid. Highest point of the alveolar ridge between P4 andM1; this has not been observed in any other species of Arcius.
Horizon and locality.—Palette (type locality, PE II, see Biostratigraphy in the following), Bouches-du-Rhône, France; Fordones (PE II, see Biostratigraphy), Aude, France; Rians (PE II; Marandat et al., 2012), Var, France.
Biostratigraphy.—There is some disagreement as to the age of Palette and
Fordones.Marandat et al. (2012) assigned Palette and Fordones to Paleocene-Eocene biozone I (PE I) and considered them intermediate in age between Silveirinha (older) and Rians/ Fournes (younger). However, there seems to be a consensus that Silveirinha is very close in age to Sotteville-sur-Mer, probably slightly younger (Smith et al., 2011; Marandat et al., 2012; Hooker, 2015), and Hooker (2015) assigned Sotteville-sur-Mer to PE II, close to the onset of the carbon isotope excursion (CIE). Rians and Fournes have been calibrated to be of similar age to the site of Meudon (Marandat et al., 2012), and Hooker (2015) suggested PE II as the age for Meudon as well. Therefore, based on the correlations suggested by Hooker (2015), Palette and Fordones would be considered to be PE II in age.
Page 1 |
Page 2 |
Page 3 |
Page 4 |
Page 5 |
Page 6 |
Page 7 |
Page 8 |
Page 9 |
Page 10 |
Page 11 |
Page 12 |
Page 13 |
Page 14 |
Page 15 |
Page 16 |
Page 17 |
Page 18 |
Page 19 |
Page 20 |
Page 21 |
Page 22 |
Page 23 |
Page 24 |
Page 25 |
Page 26 |
Page 27 |
Page 28 |
Page 29 |
Page 30 |
Page 31 |
Page 32 |
Page 33 |
Page 34 |
Page 35 |
Page 36 |
Page 37 |
Page 38 |
Page 39 |
Page 40 |
Page 41 |
Page 42 |
Page 43 |
Page 44 |
Page 45 |
Page 46 |
Page 47 |
Page 48 |
Page 49 |
Page 50 |
Page 51 |
Page 52 |
Page 53 |
Page 54 |
Page 55 |
Page 56 |
Page 57 |
Page 58 |
Page 59 |
Page 60 |
Page 61 |
Page 62 |
Page 63 |
Page 64 |
Page 65 |
Page 66 |
Page 67 |
Page 68 |
Page 69 |
Page 70 |
Page 71 |
Page 72 |
Page 73 |
Page 74 |
Page 75 |
Page 76 |
Page 77 |
Page 78 |
Page 79 |
Page 80 |
Page 81 |
Page 82 |
Page 83 |
Page 84 |
Page 85 |
Page 86 |
Page 87 |
Page 88 |
Page 89 |
Page 90 |
Page 91 |
Page 92 |
Page 93 |
Page 94 |
Page 95 |
Page 96 |
Page 97 |
Page 98 |
Page 99 |
Page 100 |
Page 101 |
Page 102 |
Page 103 |
Page 104 |
Page 105 |
Page 106 |
Page 107 |
Page 108 |
Page 109 |
Page 110 |
Page 111 |
Page 112 |
Page 113 |
Page 114 |
Page 115 |
Page 116 |
Page 117 |
Page 118 |
Page 119 |
Page 120 |
Page 121 |
Page 122 |
Page 123 |
Page 124 |
Page 125 |
Page 126 |
Page 127 |
Page 128 |
Page 129 |
Page 130 |
Page 131 |
Page 132 |
Page 133 |
Page 134 |
Page 135 |
Page 136 |
Page 137 |
Page 138 |
Page 139 |
Page 140 |
Page 141 |
Page 142 |
Page 143 |
Page 144 |
Page 145 |
Page 146 |
Page 147 |
Page 148 |
Page 149 |
Page 150 |
Page 151 |
Page 152 |
Page 153 |
Page 154 |
Page 155 |
Page 156 |
Page 157 |
Page 158 |
Page 159 |
Page 160 |
Page 161 |
Page 162 |
Page 163 |
Page 164 |
Page 165 |
Page 166 |
Page 167 |
Page 168 |
Page 169 |
Page 170 |
Page 171 |
Page 172 |
Page 173 |
Page 174 |
Page 175 |
Page 176 |
Page 177 |
Page 178 |
Page 179 |
Page 180 |
Page 181 |
Page 182 |
Page 183 |
Page 184 |
Page 185 |
Page 186 |
Page 187 |
Page 188 |
Page 189 |
Page 190 |
Page 191 |
Page 192 |
Page 193 |
Page 194 |
Page 195 |
Page 196 |
Page 197 |
Page 198 |
Page 199 |
Page 200 |
Page 201 |
Page 202 |
Page 203 |
Page 204 |
Page 205 |
Page 206 |
Page 207
