Acrolophus arcanella

Grass Tubeworm Moth
Acrolophus arcanella

POHL: 30-0080 Not listed for Canada or Ontario
MONA: 0340
GenBank: 1178030

Identification: Colour fades quickly in older individuals to dark yellowish-brown.
Head: Thick dark brown to blackish hair covers face. Eyes small, hairy (lashes) on inner eye margin. Main ID: Nose cone (palpi) on male hairy, dark brown with some brownish-yellow on inner sides; very short, projecting straight up to just above head, tips somewhat pointed. Female nose cone light brown, extremely short, projecting outward, barely visible.
Antenna: Pale yellowish-brown, reaching just past end of thorax.
Thorax: Long thick, mane-like; dark brown to blackish, often with some brownish-yellow at side edges. Female thorax more golden brown with reduced black.
Wings: Background brown-black mixed with grayish-brown. Inner margin yellowish with two yellowish triangles and with a dark triangle before and between the yellowish triangles. Female background lighter brown, inner margin tan. Fringe wide checkered dark and light.
Hind wings dark brown, tinged with black.
Legs: Dark brown, hairy, fading to yellowish-brown when older. Feet striped brown and cream. Female front leg sometimes more yellowish-brown.

Size: 12 to 16 mm long. Wingspan 28 to 32 mm.

Habitat: Dry, sandy meadows and dry forest edges.

Food: Roots and leaves of grasses. Other old reports of feeding on crop roots and young leaves of corn, wheat and clover pertained only to the 1st year of a new field on virgin soil.

Flight Time: June 28 to July 20 in s. w. Ontario.

Life Cycle: Females lay eggs (probably on soil) in July. Larvae, sometimes gregarious, form silk-lined tunnels deep in soil and feed on grass roots, or surface at night to feed on leaves. Over-winters in tunnel, pupating in late spring after feeding on young leaves.
Larvae about 22 mm. long. Velvet gray with white, shiny areas on thorax with V-shaped marks. Shield and 1st thorax segment black. Head has Y-shaped mark and a crescent groove. Antenna long, retractable. Dark legs, crochets in a circle. Adults apparently are late day-flying and also come to lights at night (mostly males).

Comments: Not listed in The Annotated Checklist of the Moths and Butterflies (Lepidoptera) of Canada and Alaska, 2018 by Pohl et al. for Canada or Ontario.
In Wheatley from late June to late July, 2011 to 2015. A. arcanella was the 2nd most common Tubeworm at the moth light.

For information on synonyms, references and type specimens see next page