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Euphranta (Rhacochlaena) canadensis (Loew)

Recognition
The connection of the apical band with the radial-medial band (the band covering crossvein R-M) distinguishes E. canadensis from the nine Palearctic species of Rhacochlaena as well as from E. mexicana, the only other New World species. See E. mexicana for additional diagnostic characters for these two species. Euphranta incompleta Hardy, from Borneo, perhaps has the most similar wing pattern to E. canadensis. White & Elson-Harris (1992: 344) redescribed the third-instar larva.

Description
Head: Ocellar seta minute or absent; 1 orbital seta, posterior seta absent; 3 (rarely 4) frontal setae, middle one usually closer to anterior than to posterior seta; arista short pubescent.

Thorax: Generally pale brown; scutum mostly orange or pale brown, with grayish microtrichia, rarely with brown postsutural sublateral vitta; scutellum pale brown, often with broad medial brown spot; mediotergite and subscutellum typically yellow with T-shaped dark-brown mark, but sometimes more extensively yellow or brown; mesonotum 1.83-2.70 mm long; thorax entirely microtrichose (except scutum medially, anterior to scapular setae), scutum with 2 paired vittae that appear shiny or darker at some angles because of microtrichia of different density or shape - these include 1 submedial vitta from anterior margin to about halfway between transverse and scuto-scutellar sutures, and 1 sublateral vitta, interrupted at transverse suture but extended to intra-alar seta; medial and lateral scapular setae present; presutural supra-alar seta absent; 1 postpronotal, 2 notopleural, 1 postsutural supra-alar, 1 intra-alar, 1 postalar, 1 acrostichal, 1 dorsocentral, 2 scutellar, 1-2 large anepisternal, 1 anepimeral, and 1 katepisternal seta present; dorsocentral seta closer to acrostichal seta than to postsutural supra-alar seta; anatergite with long fine setae.

Legs: Orange; femora without ventral spines; mid tibia with 1 large ventroapical spinelike seta.

Wing: Length 4.94-6.17 mm; radial-medial and subapical bands usually separated posteriorly (connected in posterior half of cell cu₁ in only 1 female from Maine and 1 male from Alberta among 83 specimens examined by Norrbom (1993)); apical band extended anteriorly into cell r₁ and narrowly connected to radial-medial band, in cell r₄₊₅ extended at most halfway to DM-Cu.

Male abdomen: Terga yellow, each, especially terga 4 and 5, often with mediolateral dark brown spot or band of varying size. Terminalia with surstyli very long, lateral surstylus 0.40-0.45 mm long; medial surstylus 0.90-0.95 times as long as lateral surstylus; phallus 2.08-2.54 mm long, 0.93-1.08 times as long as mesonotum; glans stout, surface largely covered with minute platelike or scalelike sculpture.

Epandrium and surstyli, posterior and lateral views; glans.

Female abdomen: Terminalia with oviscape 1.49-1.74 mm long, 0.75-0.79 times as long as mesonotum. Aculeus relatively short and broad, 0.59-0.65 mm long, 0.35-0.38 times as broad as long; tip with 3 pairs of strong steps or lobes; 3 spermathecae long and slender.

Aculeus, ventral view; spermathecae.