Scythris sinensis Felder & Rogenhofer, 1875

Landry, Jean-François, Nazari, Vazrick, Dewaard, Jeremy R., Mutanen, Marko, Lopez-Vaamonde, Carlos, Huemer, Peter & Hebert, Paul D. N., 2013, Shared but overlooked: 30 species of Holarctic Microlepidoptera revealed by DNA barcodes and morphology, Zootaxa 3749 (1), pp. 1-93 : 38-39

24. Scythris sinensis Felder & Rogenhofer, 1875 ) ( Scythrididae )

Butalis sinensis Felder & Rogenhofer, 1875 : pl. 140, fig. 11. Type locality: China, Shanghai.

BOLD:ABA2267

Palearctic distribution. Eastern Asia, Europe, Central Russia, southern Siberia ( Bengtsson 1997, Passerin d’Entrèves & Roggero 2007).

New North American records. USA: Pennsylvania, Montour Co., near Danville, 10 specimens reared from larvae feeding on Chenopodium album in July 2011 ( CNC). This is the only reported locality for North America .

Diagnosis. This is a strikingly coloured species that is unlike any North American scythridid. The pair of yellow patches on the forewings and bright yellow abdominal segments immediately distinguish it. The abdominal yellow is more extensive in females than in males. In Europe, most individuals lack the yellow spots on wings, but yellow abdominal segments are present ( Bengtsson 1997). The male genitalia are also highly distinctive with large, pincer-like valvae that are fused to the vinculum, the uncus is pointed, T8 is small and trapezoid, and S8 is broadly crescentic and has the caudal margin medially incised, the sides of the incision forming an internal ridge. In the female genitalia, the ostium is positioned slightly off on the left side of the sclerotized S8 (sterigma); the anterior edge of S8 is tightly attached to the hind margin of S7 (separated in the preparation shown).

Larval host. Chenopodium album , Atriplex patula (Chenopodiaceae) ( Passerin d’Entrèves & Roggero 2007), both of which are widespread weeds in North America.

Note. The species was first discovered in Pennsylvania in 2011 by Jesse Babonis and Steve Johnson who reared it from Chenopodium album growing alongside a house. It was easily identified from its external morphology and confirmed by genitalia examination and comparison with specimens from Japan (CNC). Currently there are no barcoded specimens of sinensis from the Old World. However, the species, which is native to Asia and the East Palearctic, has been reported in Europe since the early 1970s ( Sattler 1971) and is now known from several parts of Europe ( Bengtsson 1997; Malkiewicz & Dobrzanski 2011). It is not known whether North American occurrences originated from Europe or Asia; however, the fact that they have yellow forewing spots, which are lacking in European specimens, suggests that they may have originated from Asia.

The larvae feed on the same food plant as S. limbella (F.), which was also introduced in northeastern North America several decades ago and has since spread as far west as Montana ( Landry 1991; Powell pers. comm. to JFL, 2010). There are five junior synonyms under S. sinensis ( Bengtsson 1997; Passerin d’Entrèves & Roggero 2007). The species is apparently thermophilous and in Europe has been reported in warm spots such as along house walls and in cities ( Nupponen & Nupponen 2001; Malkiewicz & Dobrzanski 2011).