Species Ectropis crepuscularia - Small Engrailed - Hodges#6597

6597

larva known as Saddleback Looper (forestpests.org)

Ectropis crepuscularia ([Denis & Schiffermüller], 1775)

CREPUSCULARIA: from the Latin "crepusculum" - twilight

crepuscular animals are most active during twilight (dusk and dawn), whereas nocturnal animals are most active during the night, and diurnal ones during the day

Ectropis crepuscularia is the only member of the genus in America north of Mexico.

Wingspan 30-41 mm.

small black dentate (tooth-like) markings along 3 or 4 lines that cross the wing

amount of dark banding varies from heavy to almost none, but the darkest mark on the forewing is a blackish blotch along the postmedian (PM) line near the center of the wing - distinguishing this species from Protoboarmia porcelaria (Porcelain Gray), whose darkest mark is at the costa where the PM line begins

E. crepuscularia lacks a short dark streak just below the point where the antemedian (AM) line touches the costa, and usually lacks a dark spot near the middle of the hindwing (both of these marks are present in Protoboarmia porcelaria)

Some of the various forms:

Genitalia:

Coast to coast in North America, north to the panhandle of Alaska but not Yukon or NWT

also occurs throughout Eurasia

The main flight period appears to be March to October.

The larvae present in July and August in northern US and southern Canada.

The larvae are generalist feeders on balsam fir, hemlock, larch, cedar, spruce, apple, alder, birch, elm, maple, oak, poplar, and willow.

One generation in the north; 2 or 3 in the south.

Larva, larva, pupa, Mating Pair:

(both genders with simple antennae)

Porcelain Gray - Protoboarmia porcelaria which is smaller and has a short dark streak just below the point where the antemedian (AM) line touches the costa.

Powell, J.A. & P.A. Opler, 2009. Moths of Western North America. University of California Press, p. 210; plate 28, fig. 17. (1)

Moth Photographers Group (2)

The Barcode of Life Data Systems (BOLD) (3)

adult images (Larry Line)

live larva image plus text description and other info (forestpests.org)

iNaturalist