Monochroa nomadella

Monochroa nomadella (Zeller, 1868)

Figs. 21 & 22

Arkaim 14–19.VI.1996 (25♂♂, 4♀), 08–09.VII.1997 (1♂); Bajmak 17.VI.1998 (31♂♂); Berlin 30.VI– 02.VII.1997 (12♂♂); Burannoe 03.VII.2003 (1♂), 29.V.2004 (2♂♂); Chalk Hills 03–07.VI.1998 (4♂♂), 03.VI.1998 (1♂), 06.VI.1998 (2♂♂), 07.VI.1998 (1♂); Kidriasovo 28.V.1998 (2♂♂), 29.V.1998 (1♂); Kizilskoye 28.V.1998 (2♂♂); Kuvandyk 13.VI.1998 (1♀), 14.VI.1998 (2♂♂, 3♀), 15.VI.1998 (2♂♂); Moskovo 18–19.VI.1998 (3♂♂); Novoiletzk 08–09.VI.1998 (72♂♂, 22♀); Verbljushka 30.V–02.VI.1998 (3♂♂), 30.V.1998 (1♂), 31.V.1998 (1♂), 10.VI.1998 (5♂♂), 11.VI.1998 (5♂♂, 1♀), 12.VI.1998 (6♂♂), 18.VI.1999 (5♂♂), 19.VI.1999 (1♂), 31.V.2004 (1♂), 01.VI.2004 (3♂♂, 5♀); Zirgan village 24.VI.1999 (2♂♂). Genitalia slides: J. Junnilainen prep. no. 02012501, 02012505. Seven further genitalia preparations preserved in glycerol.

Remarks. The majority of the material was collected early in the morning when males were swarming around females that climbed on grasses to attract males. Occasionally specimens come also to artificial light at night (males) or can be swept during daytime (females). The wings of a female are reduced to some extent and evidently it does not fly at all (Fig. 21). The female genitalia of M. nomadella most resemble those of M. ferrea (Frey, 1870), but differ from that by a roundish, more simple signum and absence of patch of spines in the ductus bursae (Fig. 22). The female genitalia figured by Elsner et al. (1999) as nomadella differ from our material, as the signum is star-shaped and a sclerotized colliculum is situated closer to the corpus bursae. Male specimens from the Urals are identical to those from Central Europe both externally and in the genitalia, and there is no variation between specimens collected from different localities in S Ural. Therefore we believe that the female of M. nomadella has been illustrated incorrectly in earlier literature (e.g. Elsner et al. 1999), but it is also possible that a further unrecognized, closely related species exist. A description of the female genitalia is given below.

Female genitalia. Ostium half pipe-shaped, distinctly sclerotized. Antrum relatively short and membranous. Colliculum strongly sclerotized ring, located moderately close to ostium. Ductus bursae membranous, slightly widening towards corpus bursae. Elliptical corpus bursae 0.3 length of ductus bursae. Signum roundish and rough plate. Apophyses anteriores 0.85x length of apophyses posteriores.

Distribution. Locally from S and C Europe to S Ural. Outside Europe reported from Mongolia (Anikin & Piskunov 1995).