Kiel and Taviani—Miocene methane-seep bivalves from Italy


451


Figure 6. Meganodontia hoernea (Des Moulins, 1868) from the late Miocene seep deposit at Ca’ Piantè in northern Italy: (1) internal mold of left valve (MGGC 23003) showing the elongate anterior adductor muscle scar; (2) dorsal view of same specimen as Figure 6.1; (3) left valve in foreground showing posterodorsal shell margin, right valve in background showing edentulous hinge (MGGC 23004); (4) outer shell of right valve seen in the background of Figure 6.3; (5) hinge and ligament nymph in left valve (MGGC 23005).


1966 Lucina hoernea; Moroni, p. 80, pl. 3, fig. 3. 2001 Lucina Taviani, fig. 20.1. 2011 “Lucina” sp. Taviani, fig. 3a.


1901 Lucina globulosa var. perinaequilatera Sacco, p. 68, pl. 15, fig. 5.


curved in the opposite direction as shell margin, reaching below midline to ~44% of total shell height; somewhat constricted posteriorly just below the point of detachment. Interior of shell with numerous pustules, often in rows radiating form umbo; pallial blood vessel scar visible.


Description.—Very large, globular shells, height/length-ratio 0.9; umbones elevated, prosogyrate; external sculpture of fine, irregular, commarginal growth lines, posterodorsal sulcus shal- low but distinct; lunule lanceolate, bordered by sharp, smooth ridge. Hinge plate narrow to moderately broad, edentulous, ligament nymph narrow. Anterior adductor muscle scar elon- gate, detached from pallial line for ~80% of its length, angle of deviation ~30°, width about half the distance to pallial line,


Materials.—Eight specimens from Ca' Piantè (MSF 1357; 2100–2104, 2110); 45 articulated shells from Deruta (as Lucina globulosa hoernea Desmoulins, Bellardi and Sacco collection in MRSN, PU 40597–40601); one articulated shell from Bersano (as Lucina globulosa [Deshayes] var hoernea, Bellardi and Sacco collection in MRSN, BS 154.01.001); one articulated shell from Albugnano (as Lucina globulosa [Deshayes] var hoernea Desmoulins, Bellardi and Sacco collection in MRSN,


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  |  Page 208  |  Page 209  |  Page 210  |  Page 211  |  Page 212  |  Page 213  |  Page 214  |  Page 215  |  Page 216