record
| Common Name | County | Date | Observer(s) | Number | Comments | |
| 1 Horace's Duskywing | Washington | 2016-08-28 | HEL, m.ob | 1 | Pettigrew SP butterfly count | |
| 2 Horace's Duskywing | Washington | 2016-08-27 | Harry LeGrand et al. | 4 | PETT - Pettigrew SP, NC, butterfly count | |
| 3 Horace's Duskywing | Washington | 2015-09-05 | HEL, Corey, et al. | 3 | Pettigrew State Park butterfly count | |
| 4 Horace's Duskywing | Washington | 2014-08-31 | Harry LeGrand et al. | 2 | Butterfly Count | |
| 5 Horace's Duskywing | Washington | 2013-09-08 | HEL et al. | 1 | Pettigrew SP butterfly count | |
| 6 Horace's Duskywing | Washington | 2007-06-20 | S. Hartley | 4 | PETT | |
| 7 Horace's Duskywing | Washington | 2005-06-18 | S. Hartley | 1 | ||
| 8 Horace's Duskywing | Washington | 2004-06-19 | S. Hartley | 11 | ||
| 9 Horace's Duskywing | Washington | 2003-06-21 | S. Hartley | 20 | ||
| 10 Horace's Duskywing | Washington | 2002-06-22 | S. Hartley | 21 | PETT | |
| 11 Horace's Duskywing | Washington | 2002-04-02 | B. Pfeiffer | 1 | PETT | |
| 12 Horace's Duskywing | Washington | 2001-06-17 | S. Hartley | 10 | ||
| 13 Horace's Duskywing | Washington | 2000-06-25 | HEL,Pippen | 10 | ||
| 14 Horace's Duskywing | Washington | 1999-06-19 | S. Hartley | 10 | ||
| 15 Horace's Duskywing | Washington | 1997-06-21 | HEL,Hartley | 5 | ||
| 16 Horace's Duskywing | Washington | 1996-06-29 | D. Carter | 5 | ||
| 17 Horace's Duskywing | Washington | 1996-06-22 | HEL,Pippen | 8 | ||
| 18 Horace's Duskywing | Washington | 1995-06-10 | HEL | 1 | fresh female | |
| 19 Horace's Duskywing | Washington | 1994-07-16 | HEL | 2 |