045-104 Huisman.Indd 45 13-06-12 08:35 Oblique Dots Figure 1-2
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the micro moth genus AGONOPTERIX in the netherlands (lepidoptera: elachistidae: depressariinae) Hans Huisman In this paper the Dutch species of the micro moth genus Agonopterix are presented. The identification is notoriously difficult. Therefore high quality illustrations of the male and female genitalia are provided. A revision of the Dutch material proved that A. atomella and A. capreolella have to be removed from the Dutch list, whereas A. oinochra is new to the Dutch fauna. Several species have disappeared from the Netherlands, of which Agonopterix laterella is the most conspicuous. The caterpillar lives on cornflower, a beautiful blue flower that once gave colour to the Dutch agricul- tural landscape. Now it has almost disappeared, taking Agonopterix laterella along in its fall. Distribution maps and phenology charts are provided for all 23 Dutch species. introduction The genus Agonopterix Hübner, 1825 is a group genitalia of the majority of species from Western of micro moths that is notoriously difficult to and Central Europe and an indispensable base for identify. In the Netherlands the study of this further exploration, but very difficult to handle as genus has been neglected for a long time. Snellen a key, because of the variability of the characters (1882) gave useful descriptions and a key in his and some inaccuracies in the text and unclearness standard work on the Dutch Lepidoptera. Just in the rather schematic figures. A brief survey of like all his papers and books this is a work of ex- the British species was given by Jacobs (1978). cellent quality, but the key is based on external Palm (1989) published a book on the Oecophori- characters alone and is verbose and complicated dae of Northern Europe, with beautiful figures of to use. It was not until 1961 that another paper the adults. Unfortunately the photographs of the on Agonopterix was published in the Netherlands. genitalia are often disappointing. In Volume 4 of Van Laar (1961) treated the females of the genus, The Moths and Butterflies of Great Britain and based on the genitalia. He gave a key and illus- Ireland, Harper et al. (2002) treat the Oecophori- trated the eighth segment with the ostium and dae, including the Depressariinae, with detailed also the signum. Even though this is an important description of the species, keys, based on external contribution, the figures are unfortunately rather characters, for the adults and beautiful and relia- schematic and the characters in the key are not ble drawings of male and female genitalia, a great always clearly defined. Shortly afterwards he pub- improvement for our diagnostic possibilities. lished a similar paper on the male genitalia, with The appreciation of the genital characteristics somewhat better figures, but with a selection of remains difficult. Therefore it is a pity that they rather variable and partly doubtful criteria for the do not give keys based on the genitalia. key (Van Laar 1964). The need for reliable keys, together with the Abroad important papers on the genus were pub- necessity of a modern treatment of the Dutch lished by Hannemann (1953, 1954, 1958), very Agonopterix fauna, forms the motive for the thorough and detailed descriptions of the male present paper. huisman ‒ the micro moth genus AGONOPTERIX in the netherlands NFM37 (7) 045-104 Huisman.indd 45 13-06-12 08:35 Oblique dots Figure 1-2. Termen Basal area (type 1) Dark blotch Terminal dots Costa White dot Anatomical terminology. Figuur 1-2. Anatomische terminologie. Tornus (anal angle) Dorsum 1 Basal area (type 2) White dots 2 material and methods Female genitalia (fig. 4) Terminology Height of the eighth segment Distance between The used terminology is explained in figures 1-4, the posterior or anal (upper) and the anterior or and some terms in the following list. oral (lower) edge of the segment. ‘Height’ of the ostium The distance between the Forewings (fig. 1-2) anterior (oral) edge of the ostium and the anterior Costa Anterior margin (when mounted with edge of segment 8 (in fact the height of the spread wings). implantation, related to the height of segment 8). Dorsum Hind margin or inner margin in the case Lamina antevaginalis Part of segment 8 between of a specimen at rest. ostium and anterior edge. Termen Terminal (distal) margin. Lamina postvaginalis Part of segment 8 between Tornus Corner between dorsum and termen. ostium and posterior edge. Width of the bursa The transverse diameter of The terms for various dots and other markings are the bursa. explained in the section ‘External morphology’ Size of the signum In general the transverse and in figures 1 and 2. (longest) diameter. nederlandse aunistische mededelingen 37 ‒ 2012 NFM37 (7) 045-104 Huisman.indd 46 13-06-12 08:35 Dorsal Socii valva margin Figure 3. Anatomical terminology Gnathos Ventral of the male genitalia. Transtilla valve margin Figuur 3. Anatomische terminolo- gie van de mannelijke genitalia. Valve Cuiller Cornuti Anellus Aedeagus Anellus lobes Papillae anales The terms ‘height, high, low, upward and down- Height Apophyses ward’ in the description of the genitalia are in this 8th segment posteriores paper used for mere practical reasons. They are based on the usual way of illustrating the genita- Height Ostium ostium lia, not on anatomical correct positions. Apophyses anteriores Genitalia dissection Genitalia were dissected as described by Robinson (1976) and Brown (1997). To highlight the sclero- tised parts, male genitalia were stained with orange G, sclerotised parts of the female genitalia were also stained with orange G, and less sclero- tised parts were stained with chlorazol black. Genitalia were embedded on the slide in euparal. Photographs Macro photographs of the moths were taken with Ductus bursae a Nikon D80 camera, fitted with a105 mm/ f2.8 da Micro Nikkor lens. Moths were illuminated in a light-box by a circular, full spectrum fluores- cent lamp. The light-box measures 35×35×35 cm; the sides and roof are made of ‘hammered’ aluminium which disperses light; the bottom is covered with a white sheet of paper. The moths were staged on a glass screen and placed centrally in the light-box, approximately 10 cm above the Figure 4. Anatomical bottom, to avoid shadows. Photographs were terminology of the processed digitally with Adobe Photoshop cs3. Bursa copulatrix female genitalia. Figuur 4. Anatomische Microphotographs of the genitalia were made Signum terminologie van with a Nikon D300 camera, mounted on a de vrouwelijke Olympus bh-2 microscope. The magnification genitalia. changed in relation to the size of the genitalia. huisman ‒ the micro moth genus AGONOPTERIX in the netherlands NFM37 (7) 045-104 Huisman.indd 47 13-06-12 08:35 systematics The camera was computer controlled with camera Control Pro software from Nikon. Photographs The genus Agonopterix were stored directly on the hard disk of the pc. The genus Agonopterix Hübner, 1825 is the Processing of the photographs was done with largest of the five genera of the subfamily Adobe Photoshop cs4. Female genitalia figures Depressarinae, occurring in the Netherlands. were assembled from several photographs, using Some authors treat this group as a separate the stitching option in Adobe Photoshop cs4. family, the Depressariidae (e.g. Hannemann Finally to obtain higher contrast all genitalia 1995), others as a subfamily of the Oecophoridae illustrations were converted to grey scale. (Bradley et al. 1972, Harper et al. 2002), but nowadays the most cited taxonomic position is Maps and diagrams as a subfamily of the Elachistidae (Hod ges 1998, The distribution maps and the diagrams were Van Nieukerken et al. 2011). As the Depressariinae compiled from the data in ‘Noctua’, the faunistic themselves form a well-defined group, we can database of Lepidoptera in the Netherlands, man- here disregard the higher classification. aged by the Werkgroep Vlinderfaunistiek (wv In the Netherlands the genus Agonopterix has 23 in short, working group Lepidoptera faunistics, indigenous species, Depressaria Haworth, 1811 European Invertebrate Survey, the Netherlands) (13 species), Levipalpus Hannemann, 1953 (one and De Vlinderstichting (Butterfly Conservation species), Luquetia Leraut, 1991 (one species) and The Netherlands), daily manager Willem Ellis. Semioscopis Hübner, 1825 (three species). The maps and the diagrams with the number of In general we can say that recognising the sub- observed specimens per ten day period are based family is relatively easy, in contrast with the on the data of about 4300 specimens, seen by the identification of the species in the genera Ago- author. They originate from the collections of nopterix and Depressaria. As to the differentia- ncb Naturalis in Leiden (now incorporating the tion from the Oecophorinae, all Depressariinae, former Leiden collections and the former Zoolog- with the exception of the genus Luquetia, pos- ical Museum Amsterdam), Natuurmuseum Fryslan sess ocelli and in the male a spiny gnathos. in Leeuwarden and from many larger or smaller Within the subfamily the genera can be separat- private collections (from A. Cox, C. Gielis, F. ed by the presence of tufts of raised scales on the Groe nen, K.J. Huisman, J.C. Koster, J. van Vuure forewing (Luquetia) and by the absence (Semio- and J. Wolschrijn), supplemented with about 1075 scopis) or presence (the other genera) of a pecten reliable field observations. For the rarest species on the antennal scape. Of practical importance the number of specimens was too low to permit is the differentiation between Agonopterix and a graphical representation of the phenology. Depressaria, as mistakes are not infrequent. In Agono pterix the veins CuA1 (vein 3) and CuA2 The data for the distribution maps are divided (vein 2) of the forewing are stalked, in Depressa- over three periods, before 1950 (□), 1950-1979 (○) ria they arise separately from the cell. Examina- and 1980-2009 (●). tion of wing venation is by many people consid- ered difficult and therefore often not checked.