Ancylis geminana ( Donovan, 1806 )

Gilligan, Todd, Huemer, Peter & Wiesmair, Benjamin, 2016, Different continents, same species? Resolving the taxonomy of some Holarctic Ancylis Hübner (Lepidoptera: Tortricidae), Zootaxa 4178 (3), pp. 347-370 : 363-364

Ancylis geminana ( Donovan, 1806)

Figs. 26–31, 67, 81

Phalaena geminana Donovan, 1806 , Nat. Hist. Br. Insects 11: 29.

Anchylopera biarcuana Stephens, 1834 , Illust. Br. Ent. (Haustellata) 4: 113.

Phoxopterix crenana Duponchel, in Godart, 1835, Hist. nat. Lepid. Papillons Fr. 9: 334. fluctigerana [uninomial] Herrich-Schäffer, 1848, Syst. Bearbeitung Schmett. Eur. 4: pl. 45, fig. 319. [nomen nudum] Tortrix (Phoxopteryx) fluctigerana Herrich-Schäffer, 1851 , Syst. Bearbeitung Schmett. Eur. 4: 286.

Diagnosis. Ancylis geminana is distinguished by the grayish brown coloration on the costal half of the forewing, which is lighter on the costa and darker towards the longitudinal line, and the uniform curvature of the longitudinal line. It is most similar to A. christiandiana from which it differs by the distinctly curved longitudinal line and the more variegated light and dark wing pattern. The smaller A. diminutana is reddish brown with a longitudinal line similar to A. christiandiana .

Molecular data. BIN URI: BOLD:AAE1223. The intraspecific divergence of the barcode region is low with average 0.28% and maximum 0.8% (n=23). The minimum distance to the nearest neighbor A. christiandiana is 3.82%.

Redescription. Forewing. FWL Ƌ 7.5–9.5 mm (n=10), ♀ 7–8 mm (n=2). The costal half of the wing is a mix of grayish brown, dark brown, and black. The costa is lighter grayish brown with darker markings towards the longitudinal line. The dorsal half of the wing is light brownish gray to near white. The longitudinal line is continuous from base to just below the apex and is often bordered in white dorsally. The line starts at A1+2, curves evenly up to the cubitus, back down to CuA2, and then up to radius, angling down slightly to reach the termen near M1. Small black streaks are often present on R5 just proximal to the termen. Male genitalia. As described for the group. Female genitalia. As described for the group with the following modifications: apophyses posteriores and apophyses anteriores approximately the same length; antrum weakly sclerotized to the posterior 0.15 of the ductus bursae; and ductus seminalis arising in the anterior 0.3 of the ductus bursae.

Distribution. Ancylis geminana is distributed across much of Western Europe to Asia Minor, Mongolia, Siberia, China, and Japan ( Razowski 2003).

Biology. Adults are present from May to August with suspected occasional bivoltinism ( Razowski 2001, 2003). However, our data as well as various alternative literature sources (e.g. Schütze 1931) support a single generation of adults primarily in May and June. The reported larval host is willow ( Salix spp., Salicaceae ) ( Razowski 2003), although this species prefers different kind of hygrophilous to mesophilous woods such those found in riverine forests.

Remarks. Phalaena geminana was described from material collected on one occasion in Kent. Donovan (1806: pl. 370, fig. 1, 1) figured two slightly deviating specimens, indicating that the species was described from more than a singleton. No type material could be found in the collections of the Natural History Museum (London, UK), but the precise color figures of the original description leave no doubt of the identity.

Prior to the release of the first world tortricid catalogue ( Brown 2005), the majority of Ancylis in North America with a wing pattern similar to species in the A. geminana group were identified as A. diminutana . Brown (2005) realized that A. diminutana did not occur in North America, and determined that specimens in the USNM under that name were actually A. geminana . Thus, he synonymized A. diminuatana (formally determined to be nothing more than A. diminutana from North America by Heinrich) with A. geminana . He also included A. subarcuana as a synonym of A. geminana .

DNA barcode data has helped greatly in solving this taxonomic chaos. Figure 1 shows that A. geminana is clearly separate from A. subarcuana , and both are only found in the Palearctic. The remaining specimens from North America, mostly misidentified as A. carbonana , match the type of A. diminuatana . All three species can be reliably separated from each other using forewing pattern.

Figures

FIGURE 1. Neighbor-joining tree of COI DNA barcode data obtained from BOLD (K 2 P model). Clusters representing morphologically distinct species are color-coded with the corresponding species name.