| w-album Grote, Iodepepla, misspelled | 932287 | |
| walkeri Andrews, Acronicta, [Acronycta] | 931462 | |
| walkerii Grote, Eupsilia, [Dichagramma] | 932588 | |
| walshi of authors, Catocala, misspelled | 930809 | |
8630.2 | walshi Metlevski, Drasteria | 930904 | |
9348.1 | walshi Lafontaine, Apamea | 932334 | |
| walshii Edwards, Catocala | 930809 | |
11184 | walsinghami Edwards, Schinia, [Lygranthoecia] | 932154 | |
| walsinghami Butler, Spilosoma | 930313 | |
| walsinghamii Edwards, Ctenucha | 930437 | |
| Walterella Dyar | 931603 | |
| walteri Schwarz, Catocala | 930806 | |
| wanda Buchholz, Acronicta, [Acronycta], form | 931445 | |
| wardi Riotte, Orgyia | 930168 | |
| waroi Barnes & Benjamin, Arctia– ssp. | 930290 | |
| wasedana Sugi, Apamea | 932353 | |
| washingtonensis Strand, Apamea | 932323 | |
| washingtonia Grote, Lithophane– ssp. | 932545 | |
| washingtoniensis Grote, Adelphagrotis, [Agrotis] | 933641 | |
| watsoni Richards, Arugisa | 930635 | |
| wellsi Johnson, Catocala | 930821 | |
| werneri Biederman, Catocala | 930838 | |
| westcotti of authors, Catocala, misspelled | 930830 | |
| westcottii Grote, Catocala | 930830 | |
10707 | westermanni Staudinger, Euxoa, [Noctua] | 933323 | |
| westwoodi Druce, Cydosia | 931255 | |
10896.2 | whitesandsensis Metzler & Forbes, Protogygia | 933304 | |
8843 | whitneyi Dodge, Catocala | 930829 | |
9332.1 | wikeri Quinter & Lafontaine, Apamea | 932298 | |
| wilczynskia Wize, Euproctis, [Porthesia] | 930172 | |
| wileyi Dyar, Furcula– ssp., [Cerura] | 930025 | |
| williamsii Dodge, Grammia– ssp., [Arctia] | 930264 | |
8186 | williamsii Dodge, Grammia, [Arctia] | 930264 | |
| willingi Barnes & McDunnough, Dasychira, [Olene] | 930146 | |
10110 | wilsonensis Hill, Sympistis, [Oncocnemis] | 931788 | |
10867 | wilsoni Grote, Euxoa, [Agrotis] | 933486 | |
10158 | wilsoni Barnes & Benjamin, Sympistis | 931928 | |
9298 | wilsonii Grote, Xerociris, [Ciris] | 931963 | |
| winnipeg Smith, Lithophane– ssp., [Xylina] | 932580 | |
| wirima Hardwick, Euxoa– ssp. | 933423 | |
| wiskotti Staudinger, Arctia | 930290 | |
| wistroemi Lampa, Anarta | 932823 | |
9316 | wittfeldii Edwards, Alypia | 931980 | |
| wladiwostockensis Strand, Lymantria | 930141 | |
| wockei Möschler, Xestia– ssp., [Agrotis] | 933590 | |
10937 | wockei Möschler, Xestia, [Agrotis] | 933590 | |
10986.2 | woodi Lafontaine & Kononenko, Xestia | 933616 | |
| woodi Franclemont & Todd, Zale, misspelled | 931048 | |
10698.1 | woodiana Lafontaine, Feltia, [Trichosilia] | 933490 | |
| woodii Grote, Zale, [Homoptera] | 931048 | |
| worthingtoni Grote, Eucoptocnemis, [Agrotis] | 933257 | |
7932 | wrightii Edwards, Gluphisia | 930020 | |
8269 | wrightii Stretch, Cisseps, [Scepsis] | 930442 | |
| wrightii French, Leptarctia | 930336 | |
10365 | wyatti Barnes & Benjamin, Psammopolia, [Polia] | 933012 | |
| wyatti Barnes & Benjamin, Papaipema | 932476 | |
7970 | wymola Barnes, Litodonta, [Heterocampa] | 930062 | |