Loxostege sedakowialis ( Eversmann, 1852 )

Alipanah, Helen, Asselbergs, Jan, Malm, Tobias & Slamka, František, 2023, Taxonomic study of the subfamily Pyraustinae (Lepidoptera: Crambidae) in Iran, Zootaxa 5289 (1), pp. 1-82 : 52-56

Loxostege sedakowialis ( Eversmann, 1852)

( Fig. 23F )

Botys sedakowialis Eversmann, 1852: 165–166 .

LT: Russland, Eastern Siberia.

Syn.: Loxostege bashgulalis Amsel, 1970: 47 , text-fig. 18, pl. 3 fig. 33.

Material examined. 6 ♂♂, 7 ♀♀: Kermân Prov.: 6 ♂♂, 4 ♀♀, Lâlehzâr , 6, 7.vi.1971, Hâshemi, Naim leg. (gen. prep. HA-2446, HA-2449, HA-2824, HMIM) , 1 ♀, Mâhân , 2000 m, 30.vi.1977, Safavi, Pâzuki, Abâi leg. , 1 ♀, Esfandagheh , 7.v.1973, Borumand, Hâshemi leg. , 1 ♀, Darb-e Behest- Jiroft Rd. , 55 km NW Jiroft, near Shengarâ, N 29˚04΄56.5˝, E 57˚32΄25.6˝, 2794 m, 7.vi.2017, Âlipanâh, Afsariân, Mozhdehi leg.

Distribution. Russia, Afghanistan ( Amsel 1970; Koçak & Kemal 2012; Nuss et al. 2003 –2022).

Redescription of the female genitalia ( Fig. 25E, F ). Papillae anales flat, crescent-shaped, densely setose; anterior apophyses slightly less than two times the length of the posterior apophyses (n = 1); antrum nearly cup-shaped, anterior edge with denticulate sclerotization at the junction with colliculum, posterior end with a pair of rod-shaped sclerotized structures laterally; colliculum sclerotized, nearly half length of antrum; ductus bursae long, with moderate width and a distinct curvature posteriorly at the junction with colliculum; ductus seminalis from anterior end of colliculum at the junction with ductus bursae; bursa copulatrix spherical, cestum narrow, with pointed minute sclerotized spines, its length one-fifth of the length of ductus bursae.

Remarks. This species was described by Amsel (1970) as L. bashgulalis based on two males and six females collected from Afghanistan and later it was synonymized with L. sedakowialis . However, he did not present a detailed description of the female genitalia at that time. Therefore, a redescription of the female genitalia is here provided.

This species is very similar to L. clathralis externally, and as stated by Amsel (1970), they differ from each other in the length of the antennal ciliae of the male and the narrow white marginal band of both fore- and hindwing: According to Amsel (1970), length of the ciliae of male antennae in L. sedakowialis were twice as long as each segment, while in L. clathralis they were 1̸3 to 1̸2 of the length of each segment. Additionally, the wing’s narrow white marginal bands in L. sedakowialis are not interrupted by the darkened veins.

Examining a significant quantity of material of L. clathralis and 12 specimens of L. sedakowialis in the present study revealed that although the length of male antennal ciliae in these two species is very slightly different, it cannot be considered as a reliable feature because of its relativity. We observed the following differences:

1) All examined L. clathralis have brown veins, cross lines and markings; in L sedakowialis they are clearly pale brown ( Fig. 23D‒F ).

2) The wing’s narrow white marginal band is interrupted by brown veins in L. clathralis ( Fig. 23D, E ); in L. sedakowialis , the veins in this area are pale or colourless ( Fig. 23F ).

3) The narrow white marginal band of the hindwing is narrower in L. sedakowialis ( Fig. 23F ) compared to that of L. clathralis ( Fig. 23D, E ).

3) The anterior margin of the frons has a pointed medial swelling in L. clathralis ( Fig. 25A ); while in L. sedakowialis there is no pointed swelling at this area ( Fig. 25D ).

4) The brown marginal band of the hindwing is relatively broad in L. sedakowialis ( Fig. 23F ); in L. clathralis it is narrower ( Fig. 23D, E ).

Comparison the genitalia structure of these two species showed that they are very similar to each other in the male genitalia ( Fig. 24A‒G ). Amsel (1970) noted that L. clathralis has a broader fibula compared to L. sedakowialis . However, we concluded that there is an intraspecific variation in L. sedakowialis in this regard. We dissected two males with the same collecting data and external features, one with a narrow fibula ( Fig. 24E, F ) and the other one with a wider fibula ( Fig. 24G ). In both species, there is a sclerotized nearly triangular plate at the distal end of the phallus that is differently directed in each species ( Fig. 24A, B, E, D ).

These two species can easily be separated from each other based on the female genitalia structure. Their main differences are as follows:

1) In both species, the antrum is nearly cup-shaped, but its sclerotization is different. In L. sedakowialis , it is more sclerotized posteriorly and mainly posterio-laterally and anteriorly ( Fig. 25E, F ); in L. clathralis , the anterior half is more sclerotized ( Fig. 25B, C ).

3) Length of the cestum (the sclerotized band running from the mouth of appendix bursae into the anterior ductus bursae) in L. sedakowialis is nearly one-fifth of the length of ductus bursae ( Fig. 25E ); in L. clathtalis , its length is almost one-third of the length of ductus bursae ( Fig. 25B ).

2) The colliculum is half the length of the antrum in L. sedakowialis ( Fig. 25E, F ); in L. clathralis , it is clearly less than half of the antrum length ( Fig. 25B, C ).

Loxostege sedakowialis is newly reported for the fauna of Iran.

Figures

FIGURE 23. A) Sitochroa urmiensis Alipanah, male. B) S. straminealis (Hampson), male. C) S. malekalis (Amsel), male. D, E) Loxostege clathralis (Ḩbner): male, Kerman, Baft (D), male, Kashan, Jehagh (E). F) L. sedakowialis (Eversmann), male (scale bar = 10.0 mm).

FIGURE 24. Male genitalia of Loxostege clathralis (Ḩbner) (genitalia slide HA-2460, HMIM) (A–C) and L. sedakowialis (Eversmann) (genitalia slides HA-2446, HA-2824, HMIM) (D–G). A, E) Genitalia and phallus in ventral and lateral views, respectively. B, D) Distal end of phallus. C, F, G) Fibula.

FIGURE 25. A, D) Head of Loxostege clathralis (Ḩbner) (A) and L. sedakowialis (Eversmann) (D) in lateral view. B, C) Female genitalia of L. clathralis (Ḩbner) (genitalia slide HA-2823, HMIM). E, F) Female genitalia of L. sedakowialis (Eversmann) (genitalia slide HA-2449, HMIM). B, E) Genitalia in ventral view. C, F) Antrum area. Arrows in A and D indicate the anterior edge of frons.