Rhigognostis erysiphaea Meyrick 1938, comb. nov.
Creators: name: Baraniak, Edward
name: Stüning, Dieter
name: Walczak, Urszula
Publisher: name: Zenodo
Year: 2015
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Lepidoptera
Plutellidae
Rhigognostis
Rhigognostis erysiphaea

description: Rhigognostis erysiphaea (Meyrick, 1938) comb. nov.
Figs. 1–15
Plutella erysiphaea Meyrick, 1938 in Caradja & Meyrick 1938 [1939]: 25.
Type locality: China, Likiang
Holotype in Natural History Museum, London, England
Material examined. Type material. Holotype ♂, labelled: Likiang, China, 14.0 7. [19]34, gen. slide no 9449 BM. Type [white rectangular label, hand written], coll. E. Meyrick in British Natural History Museum Other material: China, Likiang, Provinz Nord-Yuennan, (correctly: Nord-Yunnan) 1 ♂ 10.0 6.1934, ca. 2000 m, leg. H. Höne (yellow label), 1 ♂ 8.0 7.1934, leg. H. Höne (grey label), 1 ♀ 10.0 7.1934, leg. H. Höne (yellow label), (gen. slide YPO80/2014), 1 ♂ 12.0 7.1934, ca. 3000 m, leg. H. Höne (yellow label), 1 ♂ 29.0 7.1935, leg. H. Höne (grey label), (gen. slide YPO79/2014), coll. H. Höne in Zoologisches Forschungsmuseum Alexander Koenig, Bonn.
Diagnosis. Rhigognostis erysiphaea can be easily distinguished from other known species of the genus by examining external features. None of the species described so far has rusty forewings. Moreover, the white line along the dorsal margin is very narrow and strongly curved.
The genitalia of both sexes are very similar in structure to those of R. schmaltzella (Zetterstedt, 1839). In males, differences concern the structure of the valva, which in R. erysiphaea is gently constricted near the costal margin, and the valval apodeme which is similar but narrower. The aedeagus in R. erysiphaea is straight with small teeth in the apical part, whereas in R. schmaltzela it is curved with larger, conspicuous teeth.
In female genitalia, the sclerotized part of the ductus bursae similarly developed and the antrum similarly shaped but more dilated. The bursa copulatrix in R. schmaltzella is large, membranous, with two well-defined signa, whereas in R. erysiphaea it is small, strongly sclerotized, and the signa absent.
Redescription. Forewing span 17–19 mm. Head dark grey, scarce white scales scattered among them. Labial palp 3- segmented: first segment dark fuscous; second with a characteristic tuft of scales, dark, with a small proportion of white scales; third segment pointed at apex, dark with a large proportion of white scales. Maxillary palp small, inconspicuous, dark grey. Antenna: scape and pedicel grey brown, flagellomeres white with grey bands.
Forewing lanceolate, wing background dark brown, with a large proportion of grey scales. Costal margin at wing base light-coloured, further parts grey brown with many small rectangular groups of black scales. Dorsal margin with a larger proportion of grey scales and conspicuous rectangular groups of black scales. From wing base, near dorsal margin, a conspicuous thin undulated pure white line, additionally strongly curved in its central part towards costal margin. Wing apex light brown, with visible black scales near cilia. Cilia coloured like wing, with a thin black cilia line at 1/2 its length.
Hindwing light grey, cilia long, dark grey.
Thorax coloured like wing base.
Abdominal segments white, with a small proportion of grey scales, only last 2 segments grey.
Description. Male genitalia (prep. gen no YPO79/2014)
Anal tube wide, long, membranous. Socii with dentate distal margin. Saccus long, narrow, with a rounded apex, longer than valva. Valva elongate, its apex gently rounded, slightly constricted ventrally; ventral margin sclerotized, with conspicuous long spines; a group of spinules visible near dorsal margin; apex membranous; near basal margin, a conspicuous apodeme, short and wide, denticulate apically; near ventral margin immediately above apodeme, a small oval sacculus with 3 long spines; in its middle part, a conspicuous group of spinules; terminal part narrower, spinules distant. Aedeagus long and thin, slightly more than twice as long as valva and saccus; constricted apically, dilated subapically, with 2 rows of spinules in subapical part. Aedeagus slightly wider and sclerotized basally. Ductus ejaculatorius membranous, very wide, sclerotized apically.
Female genitalia (prep. gen no YPO 80/2014)
Papillae anales narrow, short, membranous, covered with thin, scattered spines. Posterior apophyses long and narrow, pointed apically. Anterior apophyses markedly shorter and narrow. Initial section of antrum elongated, ending with a membranous part, while further part markedly dilated, with rounded sclerotized edges, near inception of bursa copulatrix. Duct of bursa copulatrix wide, not very long, sclerotized on one side immediately behind antrum, resulting in duct twisting. Near inception of bursa copulatrix, its duct slightly dilated, with a group of spinules visible on one side. Bursa copulatrix small, oval, strongly sclerotized. Near beginning of ductus seminalis, a conspicuous membranous broadening. Ductus seminalis initially narrow, sclerotized, remaining parts wider, membranous. Ductus bullae short, membranous, dilated to form bulla seminalis. Bulla seminalis elongate, membranous.
description: Published as part of Baraniak, Edward, Stüning, Dieter & Walczak, Urszula, 2015, Rhigognostis erysiphaea (Meyrick, 1938) comb. nov. (Lepidoptera, Plutellidae), with description of male and female genitalia, pp. 585-592 in Zootaxa 3994 (4) on pages 585-592, DOI: 10.11646/zootaxa.3994.4.7, http://zenodo.org/record/236862