- Opeia testacea Scudder, 1899: 46.
- Opeia obscura (Thomas, 1872) in Scudder & Cockerell, 1902: 25.
- Opeia imperfecta Bruner, 1904: 59.
- Opeia lineata Bruner, 1904: 61.
Syntype; ee349d69-7e50-4874-bdc0-f055af524454; Mexico: San Luis Potosí: Sierra de Miguelito
- Opeia mexicana Bruner, 1904: 60.
Holotype; female; f4d4a2d2-91c9-4fd2-b7da-665a24dad5d4; deposited at: Academy of Natural Sciences of Philadelphia (ANSP); Mexico: Distrito Federal: Tlalpam
- Opeia pallida Bruner, 1904: 60.
Syntype; c11996e8-d15b-40ac-8615-7f550ebc5810; Mexico: Coahuila: Montelovez
- Opeia palmeri Bruner, 1904: 61.
- Opeia pallida Bruner, 1904 in Rehn, 1907: 210.
- Opeia testacea Scudder, 1899 in Rehn, 1907: 34.
- Opeia imperfecta Bruner, 1904 in Rehn & Hebard, 1909: 137.
- Opeia testacea Scudder, 1899 in Rehn & Hebard, 1909: 425.
- Opeia imperfecta Bruner, 1904 in Rehn & Hebard, 1912: 111.
- Opeia mexicana Bruner, 1904 in Rehn & Hebard, 1912: 111.
- Opeia palmeri Bruner, 1904 in Rehn & Hebard, 1912: 111.
- Opeia testacea Scudder, 1899 in Rehn & Hebard, 1912: 91.
- Opeia obscura (Thomas, 1872) in Hebard, 1925: 53.
- Opeia obscura (Thomas, 1872) in Hebard, 1927: 2.
- Opeia obscura (Thomas, 1872) in Hebard, 1928: 224.
- Opeia obscura (Thomas, 1872) in Hebard, 1929: 325.
- Opeia mexicana Bruner, 1904 in Hebard, 1932: 232.
- Opeia testacea Scudder, 1899 in Hebard, 1935: 280.
- Opeia lineata Bruner, 1904 (subjective synonym of Opeia mexicana Bruner, 1904) in Hebard, 1937: 354.
- Opeia imperfecta Bruner, 1904 in Tinkham, 1948: 569.
- Opeia obscura (Thomas, 1872) in Brooks, 1958: 58.
- Opeia obscura (Thomas, 1872) in Strohecker, Middlekauff & Rentz, 1968: 78.
- Opeia testacea Scudder, 1899 (subjective synonym of Oxycoryphus obscura Thomas, 1872) in Strohecker, Middlekauff & Rentz, 1968: 78.
- Opeia obscura (Thomas, 1872) in Otte, 1981: 113, 240.
- Opeia imperfecta Bruner, 1904 (synonym of Oxycoryphus obscura Thomas, 1872) in Otte, 1981: 240.
- Opeia lineata Bruner, 1904 (synonym of Oxycoryphus obscura Thomas, 1872) in Otte, 1981: 240.
- Opeia mexicana Bruner, 1904 (synonym of Oxycoryphus obscura Thomas, 1872) in Otte, 1981: 240.
- Opeia pallida Bruner, 1904 (synonym of Oxycoryphus obscura Thomas, 1872) in Otte, 1981: 240.
- Opeia palmeri Bruner, 1904 (synonym of Oxycoryphus obscura Thomas, 1872) in Otte, 1981: 240.
- Opeia testacea Scudder, 1899 (subjective synonym of Oxycoryphus obscura Thomas, 1872) in Otte, 1981: 240.
- Opeia obscura (Thomas, 1872) in Vickery & Kevan, 1983: 1102.
- Opeia obscura (Thomas, 1872) in Vickery & Kevan, 1986: 545.
- Opeia obscura (Thomas, 1872) in Pfadt, 1988
- Opeia obscura (Thomas, 1872) in Richman, Lightfoot, Sutherland & Ferguson, 1993: 86.
- Opeia obscura (Thomas, 1872) in Johnson, 2003: 13.
- Opeia obscura (Thomas, 1872) in Capinera, Scott & Walker, 2004: 69.
- Opeia obscura (Thomas, 1872) in Rivera García, 2006: 138.
- Opeia obscura (Thomas, 1872) in Fontana, Buzzetti & Mariño-Pérez, 2008: 146-147.