Nemophora decisella ( Walker, 1863 )

Liao, Cheng-Qing, Hirowatari, Toshiya, Yagi, Sadahisa, Wang, Min, Wang, Xing & Huang, Guo-Hua, 2023, The fauna of the family Adelidae (Insecta, Lepidoptera, Adeloidea) from China, Zootaxa 5348 (1), pp. 1-152 : 38-40

(37) Nemophora decisella ( Walker, 1863)

(Plates IV-1, X-5, 7, XV-3, XXIV-2, XXIX-1-4)

Nemotois decisella Walker, 1863: 505 (Type locality: Sumatra, Indonesia; BMNH); Meyrick 1912a: 8; Meyrick 1912b: 7.

Nemophora decisella: Diakonoff 1951: 173 (Java) ; Heppner 1992 (checklist of Taiwan); Robinson et al. 1994: 23, fig. 33, pl. 3, fig. 2 ( Burma, Thailand, W Malaysia, Sumatra, Java, Anambas Is., Brunei, Kalimantan); Kozlov & Robinson 1996a: 42, figs. 2–5, 8, 9, 12–17 (review); Shao et al. 2008: 550 (Checklist of Taiwan); Koçak & Kemal 2010: 2 (checklist of Thailand).

Ucetia bifasciella Walker, 1866: 1821 (TL: Indonesia, Java; BMNH).

Nemotois bifasciella: Meyrick 1912a: 8 (Java; syn. Adela sythoffi ); Meyrick 1912b: 7.

Nemophora bifasciella: Diakonoff 1951: 179 (female, Java).

Nemophora bifasciella irrorata Diakonoff, 1951: 179 , figs. 25, 27, 30 (TL: Indonesia, E Java, Tengger Mts. ; NML).

Adela imperialis Rebel, 1900: 187 (TL: Russia, Amur; NHMW, ZMB); Szent-Ivány 1945, 8(1): 9 ( Hungary).

Nemotois imperialis: Meyrick 1912b: 7 (E. Siberia, Russia).

Nemaphora [sic!] imperialis: Gozmany 1965: 40 (Budapest) .

Adela sythoffi Snellen, 1901: 77 , pl. 5, fig. 4 (TL: Indonesia, W Java, Preanger ; female; NML).

Nemotois sythoffi: Meyrick 1912a: 8 (as junior synonym of N. bifasciella ).

Nemotois baibarana Matsumura, 1927: 7 (TL: Taiwan, China; EIHU); Matsumura 1931: 1111, fig. 2333 (female, Taiwan); Matsumura 1932: 123, pl. 4, fig. 8 (Formosa [ Taiwan]); Razowski & Kumata 1985: 5 (Type catalog); Hua 2005: 2 (list of China).

Nemotois honei Meyrick, 1935 , 94 (TL: China, Nanking [Nanjing]; BMNH); Hua 2005: 2 (list of China).

Adela aurantibasella Caradja, 1938a: 252 (Type locality: China, Shaowu ; MINGA).

Adela aurantivasssella [sic!]: Hua 2005: 2 (list of China).

Diagnosis. This species is very similar to N. paradisea but can be distinguished by the following combined characters: the forewing central fascia is very narrow, placed between basal 1/3 to 1/2; the eye size index is about 6 in male adult; the apex of valva is relatively rounded; the sacculus has a distinct angular process in the middle; the suspensorium is far beyond the posterior margin of the vinculum; and the apex of aedeagus is an extremely bent forming wave.

Specimens examined. [Hunan] 1♁ 9♀, Guniushan Village (800 m), Wuyunjie National Nature Reserve, Taoyuan County, Changde City , 2019.VI.24, C.Q. Liao, C.J. Yang & Q.M. Wu leg. ; 5♀, Xianchijie, Wuyunjie National Nature Reserve, Taoyuan County, Changde City , 2020.VI.10–16, C.Q. Liao leg. ; 1♁ 2♀, Mt. Tianpingshan, Badagongshan National Nature Reserve, Sangzhi County, Zhangjiajie City , 2020.VI.19–23, C.Q. Liao leg. ; 1♀, Mt. Tianpingshan, Badagongshan National Nature Reserve, Sangzhi County, Zhangjiajie City , 2020.VII.5, C.Q. Liao & M. Deng leg. ; 1♀, Mt. Tianpingshan, Badagongshan National Nature Reserve, Sangzhi County, Zhangjiajie City , 2018.VIII.10–11, C.Q. Liao leg. ; 1♀, Mt. Tianpingshan, Badagongshan National Nature Reserve, Sangzhi County, Zhangjiajie City , 2014.VIII.12–13, G.H. Huang leg. ; [Guangdong] 1♁ 1♀, Nanling National Nature Reserve, Ruyuan Yao Autonomous County, Shaoguan City , 2008.VI.7, G.H. Huang leg. ; 1♀, Jiulianshan, Lianping County, Heyuan City , 2018.V.18–19, M. Wang & F.H. Wei leg. ; [Sichuan] 1♁, Shimian County, Ya’an City , 2016.VII.10, T.T. Yu leg ; [Shaanxi] 1♁, Huameiguan, Liuba County, Hanzhong City , 2018.VIII.10–11, C.Q. Liao & G.H. Huang leg. ; 1♀, Jialingjiang source, Baoji City , 2018.VIII.13, C.Q. Liao & G.H. Huang leg. ; [Zhejiang] 1♀, Tianmushan, Hangzhou City , 2011.VII.8, G.H. Huang leg. ; [Fujian] 1♀, Taiping Town, Nanping City , 2002.IV.4, G.H. Huang leg. ; [Hainan] 1♁, Jianfengling National Nature Reserve, near Resort Hotel (900 m), Ledong County, 2004.V.21, M. Wang leg. ; 1♁, Jianfengling National Nature Reserve , Ledong County, 2021.V.18, M.R. Li & G. Fu leg. ; 1♀, Jianfengling National Nature Reserve , Ledong County, 2007.IV.23, M. Wang leg. ( HUNAU) .

Distribution. China (Hunan, Guangdong, Sichuan, Shaanxi, Hubei, Zhejiang, Jiangsu, Fujian, Hainan, Taiwan); Russia, Korea, Myanmar, Thailand, Indonesia, Malaysia, Brunei, etc.

Remarks. The distribution of this species is extremely wide, ranging from the northernmost Russian Khabarovsk region to Southeast Asia including Malaysia and Indonesia, and includes most areas of central and south China. Given its widespread distribution, this species may be distributed in the northeast of China.

Because of its wide geographical distribution, relatively large intraspecific variation and typical sexual dimorphism, this species has been described as having more than seven different specific names. Walker (1863) first described this species based on a single male specimen from Sumatra but incorrectly transposed the English descriptions and localities with N. sinicella (Meyrick, 1912) . Walker (1866) estimated Ucetia bifasciella (= Nemotois bifasciella ) based on a female specimen from Java, which incorrectly regarded it as a separate species because Walker misidentified the sex of type specimen of N. bifasciella ( Kozlov & Robinson, 1996a) . Many different species names have been named by different researchers based on specimens from the Russian Far East, Japan, China, and Southeast Asia, such as Adela imperialis Rebel, 1900 , Adela sythoffi Snellen, 1901 , Nemotois baibarana Matsumura, 1927 , Nemotois honei Meyrick, 1935 , Adela aurantibasella Caradja, 1938 . After Kozlov & Robinson (1996a) examined a large number of type specimens, they synonymized several species names as above considering the combination of geographical variation in its external characteristics and sexual dimorphism. In addition, they also considered that N. heteroxantha established by Diakonoff (1951) based on female specimens from East Java (the type locality of N. bifasciella irrorata ) is probably a synonym of N. decisella . In the original paper, when Diakonoff named N. heteroxantha , he also described N. decisella again and noted that this species became rarer due to the destruction of lowland forest habitat in Java after the war ( Diakonoff 1951). Because no males of N. heteroxantha are known and females differ in some traits from N. decisella , N. heteroxantha was considered as an independent species ( Kozlov & Robinson 1996a). According to Kozlov & Robinson (1996a), some characteristics of this species seem to change following latitudinal variation, for example, forewing length and male eye size are greater further south, but the relative width of the forewing yellow band decreases southwards, while the position of the central fascia becomes progressively closer to the middle of forewing.

This species mainly occurs in the summer, with high temperatures from May to August, and the earliest collection records can be up to the early spring of February. This species is distributed from lowlands to mountainous areas at altitudes of more than 2,000 meters and its main habitat is mountainous and virgin forests ( Robinson et al. 1994; Kozlov & Robinson 1996a). However, the host plant of this species has not yet been reported. During a field survey in Wuyunjie Nature Reserve, Hunan in June 2019, the first author (C.Q. Liao) observed that the female adults of this species nectar the flowers of one Primulaceae plant, Lysimachia sp. (probably L. clethroides Duby ) and ovipositing at the base of unopened flower buds (Plates XXIX-1-4). Although laboratory rearing of the oviposited plants was ussuccessful, we believe that the host (oviposition) plant and nectar source of N. decisella should be Lysimachia sp.

DNA barcodes of three N. decisella specimens are generated, and their sequences show 0.5–0.9% differences. This species is closest to N. sakaii with pairwise distances of 0.043 –0.051.