Tetracis formosa (Hulst, 1896)
Family: Geometridae
Subfamily: Ennominae
Identification: Antenna nearly white dorsally, bipectinate in male, nearly filiform in female and densely setose ventrally. Head (frons gray), abdomen, legs gray to gray-brown, varying in color according to habitat. Montane specimens are mostly gray, high-desert specimens gray-brown, becoming paler at lower elevations in California. Wings: Base color pale gray to white; overall aspect gray to gray-brown because of overlying gray, brown, and dark brown scales. FW apex acute but barely falcate. AM and PM lines dark brown; PM line narrow, sinuate, with a narrow white outer border its entire length. AM line with narrow white border basad; AM line angles diagonally outward and upward from inner margin, terminating at the dark discal spot. MB at most only slightly darker than basal area. Submarginal area divided by narrow irregular dark brown band; in many specimens the wing color is paler distad of this band. Veins outlined in white. DHW paler centrally with darker shading along outer margin; dark brown median line irregular, us
Wing Span: 3.4-4.6 cm
Life History:
Flight: early September to late November
Caterpillar Hosts: Incompletely known. Prunus andersonii (Desert Peach)
Adult Food:
Habitat: Habitats range from desert riparian canyons (Colorado, Utah) to dry coniferous forest (Wyoming)
Range: Colorado, eastern Utah, and eastern Wyoming west to Caifornia and north to southern British Columbia and southern Alberta from 2850–7600’ (870–2320m).
Conservation:
NCGR:
Management Needs:
Taxonomy Notes: None.
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Verified Sightings
Displaying 1 - 4 of 4 verified sightings

Observation date: Sep 24, 2018
Submitted by: hydapse
Region: Carbon County, Montana, United States
Verified by: davidwdroppers
Verified date: Oct 08, 2018

Observation date: Oct 02, 2015
Submitted by: Sue Orlowski
Region: Grant County, Washington, United States
Verified by: davidwdroppers
Verified date: Oct 21, 2015

Observation date: Sep 05, 2013
Submitted by: Dwaine Wagoner
Region: Natrona County, Wyoming, United States
Verified by: J_Martineau
Verified date: Sep 06, 2013

Observation date: Sep 28, 2011
Submitted by: roadrunner
Region: Campbell County, Wyoming, United States
Verified by: J_Martineau
Verified date: Apr 26, 2012