Alcathoe caudata

Clematis Clearwing
Alcathoe caudata

POHL: 64-0172
MONA: 2623
GenBank: 1029665 tentative

Identification: Note: Colours are variable.
Head: Black. Nose cone (palpi) bright orangish-yellow, reaching to top of head. Darker orangish-yellow stripe entirely across back of head.
Antenna: Bright orangish-yellow. Long, reaching to mid-wing. Males may have some black scaling on top side, from base to almost mid-length of antenna.
Thorax: Reddish to purplish-black. Male thorax may have some orange tuft-like scaling.
Wings: Male forewing reddish to purplish-black, may have streaked, transparent area before middle of the wing, absent on worn individuals.
Female forewing entirely reddish to purplish-black.
Both have hindwings transparent with reddish to purplish-black borders and a thick mark across wing.

Legs: Male: Bright yellow to orangish. Thighs (femora) with thick black scaling on top side. Hind shin has patch of black hairs. Hind foot (tarsi) has tuft of orange scales at base. Worn individuals have legs almost entirely pale yellow.
Female: Thighs (femora) black; middle and hind shin (tibiae) black. Rest of legs and feet yellow to orangish. Front foot has tuft of black at base, absent in worn individuals.
Abdomen: Reddish to purplish-black on both sexes. Female has black, squarish tuft at abdomen tip. Male has black tuft each side of abdomen tip and a bright yellow to orangish tail which is as long as the abdomen. Underside orange.

Size: 10 to 15 mm long. Wingspan 20 to 32 mm.

Habitat: Wet forests, streambanks with Virgin’s Bower (also called Woodbine).

Food: Adults feed on flower nectar, mostly the host plant flowers. Larva feed on the roots and stems of Virgin’s Bower Clematis virginiana.

Flight Time: July and August

Life Cycle: Females lay eggs on our only native Clematis, Virgin’s Bower Clematis virginiana. Females are reported to lay eggs at the root of the plant, but photographs show the female laying eggs on the underside of leaves. Larvae feed in the roots near the soil surface, or in the larger plant stems that reach the ground. Larvae 14 mm long, dull white with 2 rows of tiny brown dots; brownish head and legs. Shield is light brown with 2 oblong, slanted dark brown spots, almost joined at bottom. Pupates in a silken mass mixed with debris and over-winters. Chrysalis formed inside cocoon is spined and helps the moth move to surface of root or stem to emerge in July. One generation per year. Reports of feeding on Currant Ribes are in error. All Alcathoe species or sub-species feed only on Clematis.

Comments: Rare. Essex County – Wheatley per photos. Also recorded in Toronto and Belleville area. Two specimens in the Canadian National Collection (CNC). Note: DNA problems. See next page.

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