In order to study the distribution of E. innotata (Hufnagel) and E.
ochridata Schütze & Pinker in Denmark we examined 1053 specimens of this species-pair. Altogether 397 genitalia preparations were made (269 of E. innotata and 128
of E. ochridata) using standard methods: Genitalia were prepared
by macerating in 10% KOH, clearing, staining with chlorazol black
and dehydrating in alcohol. Preparations were preserved in Euparal on slides or, in some cases, in glycerol in plastic tubes, mounted on the pin with the specimen. If there were more specimens from the same locality only one or few specimens
from the group were checked by making genitalia preparations.
Photos of genitalia structures were made using Leica Application Suit (v. 4.0.0) and Zerene Stacker program for stacking subsequent images. Photos of specimens were made the same way. We found constant differences in genitalia structures which are summarized below: Male genitalia of E. innotata and E. ochridata can be distinguished by two major differences (fig. 16-22): 1. The phallus (aedeagus) of E. innotata has normally only one distinct horn-like cornutus in the middle part of phallus (fig. 16, 17), while in the phallus of E. ochridata there are usually two smaller horn-like cornuti – one in the middle part of phallus, another one is situated close to the distal end (fig. 20, 21). In some rare cases the cornutus situated in the middle of phallus is reduced and can be overlooked while checking genitalia preparations (fig. 18, 22). 2. The valvae of E. innotata has in the lower middle part no distinct projection, while in E. ochridata this projection is distinct and clearly visible. Female genitalia of E. innotata and E. ochridata can be distinguished
by three major differences (fig. 23-24): 1. In the bursa copulatrix the clear area without sclerotized spines around ductus seminalis is rather small in E. innotata, and the upper line of the sclerotized spines is more or less strait, while in E. ochridata this clear area is much wider and extents deeper down towards the middle of bursa. 2. The lamella postvaginalis has a different shape: in E. innotata it has step-like bend on both sides, while in E. ochridata it has no bend and generally is oval-shaped. 3. Ductus seminalis in E. innotata enters from the right side of corpus bursa (seen from dorsal side), while in E. ochridata it enters from the central or left side. We compared specimens of the two species identified by the above Lepidoptera bind X, nr. 4, 2012 129 mentioned differences in the genitalia. The only difference in the appearance we have been able to find is that in some (but not all!) specimens of E. ochridata is an elongated bright spot just before the black middle spot of the forewing. This is not seen - or only indistinctly
- in E. innotata. This means that specimens without this bright
spot can be both E. innotata and E. ochridata. Therefore, it will
often be necessary to examine the genital organs in order to reach a safe determination of the two species. Data from all examined specimens were entered into Bugbase (www.lepidoptera.dk/bugbase) which generated distribution maps
and diagrams of flying periods for the two species. Both species have two generations in Denmark (Figs 25-26), and they are both mainly distributed in the eastern parts of the country, and only E. innotata reaches western Jutland (Figs 27-28). E. ochridata has its northwesternmost limits of distribution in Denmark.
Our study did not focus on the biology of these two species, and it suffered from the fact that larval host plant information is missing on most labels of the studied specimens. We examined bred specimens of E. innotata with such information only from Artemisia campestre, whereas bred specimens of E. ochridata from Crataegus, Achillea millefolium and Tanacetum vulgare were examined. We found no evidence for the existence of a third species, E. fraxinata Crewe, 1863 in our study.