3.2 Nemophora sichuana species group

Nemophora sichuana group (Liao et al. 2021: 17)

Diagnosis. This species group is characterized by the typical forewing pattern and male genitalia with the following features: the valvae are ventrally separated; the sacculus is basally swollen to some degree with dense hairs; the apical portion of the aedeagus bears a weak lamellate keel dorsally; the manica has a patch of minute spines dorsally; and the forewing pattern is characterized by a subapical spot, transverse central fascia, and a pair of longitudinal basal striae.

Remarks. Hirowatari et al. (2012) described four Chinese Nemophora species, N. sichuana, N. tenuimaculata, N. tadauchii, and N. kozlovi, from the high mountainous areas of Yunnan and Sichuan, and considered that these species are closely related to N. pruinosa and N. umbripennis from the Ryukyus and mainland Japan, respectively. Liao et al. (2021) grouped these four species and one new species N. zheduoshana within the sichuana species group. The members of this species group inhabit the high mountainous areas of central China around the Himalayas, but there are some differences in their distribution. Some species may speciate allopatrically speciated at high elevations in their respective mountainous areas.

In addition, one species from Kazakhstan, namely Adela ommatella Caradja, 1920 deposited in MINGA, is very similar to the N. sichuana species group. The original description and the type species photograph show that the forewing has a narrow white transverse central fascia and a circular yellowish subapical spot (Caradja 1920). Therefore, this species may belong to the sichuana species group.

Key to species of the sichuana group based on external morphology

1 Central fascia of forewing complex forming a long transverse band.............................................. 2

- Central fascia of forewing discontinuous, represented by a pair of small spots........................ N. tenuimaculata

2 Forewing with short basal striae, not reaching the midpoint of central fascia....................................... 3

- Forewing with long basal striae, beyond the midpoint of central fascia........................................... 4

3 Subapical spots of forewing circular; hindwing generally with small spots; abdomen yellow and white dorsally... N. sichuana

- Subapical spots of forewing oval, stilliform; hindwing without small spots; abdomen black dorsally........ N. zheduoshana

4 Male eyes moderate in size, eye size index about 1.0; forewing length 5.5–6.2mm; subapical spots oval....... N. tadauchii

- Male eyes small, eye size index 0.60–0.64; forewing length about 7.0 mm; subapical spots guttiform............ N. kozlovi

Key to species of the sichuana group based on male genitalia

1 Valva triangular in ventral view.......................................................................... 2

- Valva nearly quadrate in ventral view........................................................ N. tenuimaculata

2 Valva bifurcated in lateral view................................................................. N. tadauchii

- Valva not bifurcated in lateral view....................................................................... 3

3 Valva widely separated ventrally; sacculus slightly swollen basally................................... N. zheduoshana

- Valva narrowly separated ventrally; sacculus distinctly swollen basally........................................... 4

4 Juxta with relatively small sickle-shaped arrow-head................................................. N. sichuana

- Juxta with large trapezoidal arrow-head............................................................. N. kozlovi