Life Forms (Genus) by First Letter of Name)
| Globally Extinct | Partially Extinct | Letter Total |
 | 6,069 | 663 | 6,733 |
 | 2,968 | 295 | 3,263 |
 | 6,022 | 942 | 6,964 |
 | 2,884 | 281 | 3,165 |
 | 3,396 | 342 | 3,738 |
 | 1,051 | 107 | 1,158 |
 | 2,228 | 275 | 2,503 |
 | 2,813 | 359 | 3,172 |
 | 1,043 | 84 | 1,127 |
 | 553 | 33 | 586 |
 | 1,654 | 46 | 1,700 |
 | 3,005 | 439 | 3,444 |
 | 4,312 | 543 | 4,856 |
 | 2,015 | 254 | 2,269 |
 | 1,663 | 218 | 1,881 |
 | 11,027 | 965 | 11,992 |
 | 256 | 12 | 268 |
 | 1,910 | 192 | 2,102 |
 | 5,651 | 608 | 6,259 |
 | 3,798 | 449 | 4,247 |
 | 527 | 42 | 569 |
 | 844 | 99 | 943 |
 | 679 | 17 | 696 |
 | 368 | 32 | 400 |
 | 357 | 5 | 362 |
 | 478 | 67 | 545 |
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