♂, Chiang Mai, Thailand.		♀, Chiang Mai, Thailand.
♂, Yala, Thailand.		♀, Surat Thani (Koh Phangan), Thailand.
♂, Chanthaburi, Thailand.		♂, Phetchaburi, Thailand.

ON : Lycaenesthes merguiana Moore, 1884 OD : J. asiat. Soc. Bengal (Part II), 53(1): 23. TL : "Mergui" [Myeik, Myeik Dist., Myanmar]. (NZC) Distribution : Sikkim to Myanmar, Yunnan, Thailand, Laos, Cambodia, Vietnam, Hainan, Langkawi, W.Malaysia, Tioman, Singapore, Borneo, Sumatra, Nias, Simeulue, Enggano, Palawan.

Type ♂, 1882.iii.21. Mergui, Burma. (NZC) ; Sheela et al.,2019 : 119, figs.♂(Un),♂.

[ THAILAND ]
Nacaduba viola merguiana ; Godfrey,1930 : 321-322. (Chiang Rai)
Ionolyce helicon merguiana ; Pinratana,1981 : 63, pl.10, fig.19,♂(Un). (Chiang Mai; Chanthaburi; Nakhon Nayok; Ranong; Trang; Yala)
Nacaduba beroe gythion ; Ek-Amnuay,[2007] : pl.264, figs.136,♂,♂(Un),♂,♂(Un). (Chanthaburi)
Ionolyce helicon merguiana ; Ek-Amnuay,[2007] : 583, pl.264, figs.L139,♂,♂(Un),♀,♀(Un). (Chiang Dao; Chanthaburi)
Ionolyce helicon merguiana ; Les Day,2011–2022 : Samui Butterflies, figs.♂(Un),♀(Un). (Koh Samui) (accessed: 2021.06.14)
Ionolyce helicon merguiana ; Ek-Amnuay,2012 : 606, pl.275, figs.L164,♂,♂(Un),♀,♀(Un). (Chiang Dao; Chanthaburi)
Ionolyce helicon merguiana ; Okamoto et al.,2013 : 6. (Kanchanaburi: Mae Klong Station)
Ionolyce helicon merguiana ; Kimura et al.,2014 : 165, figs.♂,♂(Un),♂,♂(Un),♀,♀(Un). (Nakohn Nayok; Kao Soi Dao; Kratchin WF; Kan Puan; Muang Shone; Ka Chong; Thaleban; Than To WF.)
Ionolyce helicon merguiana ; K. Chaianunporn & T. Chaianunporn,2019 : 85. (Chaiyaphum: Chulabhorn Dam)
Ionolyce helicon merguiana ; Küppers & Janikorn,2020 : 166, figs.Abb.L-210-213. (Phang Nga)
Prosotas aluta nanda ; Küppers & Janikorn,2020 : 168, figs.Abb.L-227. (Phang Nga)
Ionolyce helicon merguiana ; Sophonviwatkul et al.,2015– : Butterflies of Thailand, figs. (Kanchanaburi; Sa Kaeo; Phetchaburi; Yala) (accessed: 2023.05.07)

[ LAOS ]
Ionolyce helicon merguiana ; Motono & Negishi,1989 : 72, not fig. (Vang Vieng; Phatong)
Ionolyce helicon merguiana ; Osada et al.,1999 : 215, pl.111, figs.♂,♂(Un),♀. (Thabok; Xam Neua)
Ionolyce helicon merguiana ; Onodera,2009b : 43. (Bolikhamxai: Phon Si)
Ionolyce helicon merguiana ; Nakamura & Wakahara,2012 : 52.
Ionolyce helicon merguiana ; Suwa et al.,2013 : 26. (Thabok; Nahin)
Ionolyce helicon ; Suwa et al.,2019 : 30. (Nam Pheng; Thabok)
Ionolyce helicon merguiana ; Onodera,2022 : 81, pl.212, figs.♂,♂(Un),♀,♀(Un). (Bolikhamxai: Konglor; Xiengkhouang: Tha)

[ CAMBODIA ]
Ionolyce helicon merguiana ; Monastyrskii et al.,2011 : 130. (Phnom Samkos W.S.)
Ionolyce helicon merguiana ; Kosterin,2019 : 94. (Koh Kong)
Ionolyce helicon merguiana ; Chartier & Kosterin,2022 : 121. (Koh Kong; Pursat)

[ VIETNAM ]
Ionolyce helicon merguiana ; Ikeda et al.,2001 : 51, figs.3:19,♂,20,♂(Un),7:27(♂genitalia). (Cuc Phuong)
Ionolyce helicon merguiana ; Luong et al.,2004 : 10. (Cuc Phuong)
Ionolyce helicon ; Monastyrskii et al.,2006 : 43. (Thua Thien Hue: A Luoi; Huong Thuy; Bach Ma)
Ionolyce helicon merguiana ; Miyazaki et al.,2006d : 57, fig.L-64,♂. (Lam Dong: Dambri)
Ionolyce helicon merguiana ; Monastyrskii & Devyatkin,2015 : 53. (N / C / S)

[ THAILAND ]
Mae Hong Son : 3♂ (photo).

Jan

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Chiang Rai : 1♂ 1♀.

Jan

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Chiang Mai : 9♂ (incl. photo).

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Nan : 1♂.

Jan

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Tak : 2♂.

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Chanthaburi : 2♂.

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Trat : 1♂.

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Phetchaburi : 1♂.

Jan

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Ranong : 7♂.

Jan

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Surat Thani (Koh Phangan dist.) : 1♂ 1♀.

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Krabi : 1♂.

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Yala : 7♂ 1♀ (incl. photo).

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The butterfly is not uncommon in forests at low to high elevations (Alt. 50 - 1750m). Males are territorial on trees or shrubs at hilltops and, like Nacaduba, prefer to settle at the tips of twigs. Males are frequently observed mud-puddling along stream banks and at puddles.

Moore, F.,1884 : Descriptions of some New Asiatic Lepidoptera; chiefly from Specimens contained inthe Indian Museum, Calcutta.
J. asiat. Soc. Bengal (Part II), 53(1): 16-52.

Tite, G.E.,1963 : A Synonymic List of the Genus Nacaduba and Allied Genera (Lepidoptera: Lycaenidae).
Bull. Br. Mus. nat. Hist. (Ent.) 13(4): 69-116, 91 tf, 2 pls. London.

♂, Chiang Mai, Thailand.	♀, Yala, Thailand.
♂, Chiang Mai, Thailand.

1999.07.11 - 2026.04.30.