蝶と蛾 Science 68（2）: 53-60, August 2017

Description of a new species, Acidon sugii from Ogasawara（ Bonin） Islands, Japan with its standard DNA barcode information（ , ） 1） 1, 2）* 3） 3） 4） Daisuke Watabiki , Shin-ichi Yoshimatsu , Koji Takeuchi , Takashi Ohbayashi and Hiroshi Nagano 1） Graduate School of Agriculture, Tokyo University of Agriculture, Funako 1737, Atsugi, Kanagawa, 243-0034 Japan 2） National Agriculture and Food Research Organization, Institute for Agro-Environmental Sciences, Kannondai 3-1-3, Tsukuba, Ibaraki, 305-8604 Japan 3） Tokyo Metropolitan Agriculture and Forestry Research Center, Fujimi-cho 3-8-1, Tachikawa, Tokyo, 190-0013 Japan 4） Japan Wildlife Research Center, Kotobashi 3-3-7, Sumida-ku, Tokyo, 130-8606 Japan

Abstract A new species, Acidon sugii sp. nov. is described from Ani-jima, Chichi-jima and Haha-jima Islands of the Ogasawara Islands, Japan with illustrations of the male and female genitalia. The Acidon is newly recorded from Japan. The new species can be distinguished from the closely related species, A. calcicola by the bipectinate male antennae and short and centrally obtusely flexed aedeagus. Perciana marmorea and nakatanii are successfully distinguished using standard DNA barcoding.

Key words Catocalinae, DNA barcoding, Hepatica, Mecistoptera, Micronesia, mtCOI, .

Introduction The Ogasawara（ Bonin） Islands are located in the northwest Pacific, roughly 1,000 km south of the main Japanese Archipelago The “Mecistoptera generic group” sensu Kononenko and and were registered as a world natural heritage site in 2011. The Behounek（ 2009） and Kononenko and Pinratana（ 2013） has Islands have about 800 recorded species and the ratio of been considered to have intermediate features between the endemic insect species is about 30%（ Kato, 1992）. Currently, Herminiinae and Hypeninae; it includes the following eight many insect species endemic to the Ogasawara Islands are genera, Mecistoptera Hampson, Acidon Hampson, Perciana threatened with extinction because of predation by an alien Walker, Hiaspis Walker, Hepatica Staüdinger, Coarica Moore, lizard species of green anole, Anolis carolinensis Voigt. Ruttenstorferia Lödl and Lophomilia Warren, based on the Therefore, countermeasures against this threat have been carried similarity of their genitalic characters. According to Holloway out by the Ministry of the Environment（ MOE）, using adhesive （2008）, the group should probably also include the dubiously traps to capture the lizard（ Takahashi et al., 2014）. associated genera, Gonoglasa Hampson; he also mentioned that the group is still tentative. The third author found some unknown mature lepidopteran larvae on Distylium lepidotum Nakai（ Hamamelidaceae） on The genus Acidon comprises 21 species（ including two Chichi-jima Island in January, 1996. After feeding on D. unidentified species） which are distributed in the Indo- lepidotum, the larvae pupated and adults emerged successfully Australian region. By making reference to the type specimens of （Fig. 1）. The late Mr Shigero Sugi tried to identify them most species, Lödl（ 1998） redescribed and illustrated all hitherto unsuccessfully. Consequently, Takeuchi and Ohbayashi（ 2006） known species of the genus Acidon. He also suggested that the recorded this unknown species as a member of the Herminiinae genus belonged among the “true” Hypeninae, falling within a without giving a generic or species name. The first author found group of genera near the genus Hypena Schrank. Holloway a male adult of the same species captured in an adhesive trap on （2008） described seven new species and reported the above Ani-jima Island（ Fig. 2） in January, 2015. We therefore mentioned two unidentified species from Borneo Island. investigated the species using the genital morphology of both Kononenko and Pinratana（ 2013） also reported an unidentified sexes, and molecular data from the mitochondrial DNA（ COI）. specimen from Thailand. In this paper we use the subfamily As a result we were able to recognize it as a new species of the name Hypeninae and family name Erebidae following the genus Acidon belonging to the subfamily Hypeninae of the treatment of Zahiri et al.（ 2012）, who revised the classification family Erebidae sensu Zahiri et al.（ 2012） as mentioned above. of the superfamily Noctuoidea using mitochondrial and nuclear DNA.

*Corresponding author E-mail: [email protected] 54 D. Watabiki et al.

Fig. 1. A male adult of Acidon sugii sp. nov., reared from a larva Fig. 2. A male adult of Acidon sugii sp. nov.（ LC159392） and pictured by K. Takeuchi in 1996. captured on an adhesive trap for green anole. Photo by D. Watabiki at Ani-jima Island in January, 2015.

Materials and methods of 94°C for 30 sec, 44°C for 30 sec（ LC159395-LC159398, LC159400）, 46°C for 30 sec（ LC159392-LC159394） or 47°C for Morphological studies 30 sec（ LC159399） and 72°C for 1 min with final extension at The present study is based on 23 adult specimens collected from 72.0°C for 5 min. Only one specimen of A. sugii（ LC159393） was Chichi-jima, Ani-jima and Haha-jima Islands. Their detailed amplified by second PCR whose cycling conditions were 94°C locality and collecting dates are written in the descriptions. For for 5 min, 35 cycles of 94°C for 30 sec, 44°C for 30 sec and 72°C dissecting and observing the male and female genitalia, the for 1 min with final extension at 72.0°C for 5 min． PCR was abdomen was removed and boiled in 5% KOH solution for about performed in a reaction volume of 20μl of GoTaq（ Promega） 5 minutes. （LC159395, LC159399, LC159400） or Ex-taq（ 3.2μl of dNTP Mixture, 4.0μl of 10×EX Taq Buffer（ Takara Bio Inc., Tokyo, DNA experiments Japan）, 0.4μl of TaKaRa EX Taq（ Takara Bio Inc.）） One adult specimen of the present species from Ani-jima Island （LC159392-LC159394, LC159396-LC159398）, 40μl using 3.2 and two adult individuals of the same species from Haha-jima μl of each primer（ 10 μmol/l）, 1.6μl of template DNA and 12μl Island were used for DNA investigation. Perciana marmorea of SDW. We asked Takara Bio Inc. to do the analysis of Walker from Vietnam and Laos, and Hepatica nakatanii Sugi nucleotide sequences by direct sequencing using a Big Dye from Yaku-shima Island were also used for the purposes of Terminator v3.1 Cycle sequencing kit（ Applied Biosystems Inc., comparison. juno（ Dalman） from Yaku-shima Island was Foster City, CA, USA） and an ABI 3730-XL genetic analyzer utilized as an outgroup species. Three right or left side legs of （Applied Biosystems Inc.）. Sequences were edited with specimens were removed and put into 99.5% ethanol for DNA sequence assembly software ATGC（ Genetyx Inc., Tokyo, extraction. DNA was extracted using a DNeasy Blood & Tissue Japan） and we used MEGA v6 software（ Tamura et al., 2013） Kit（ Qiagen N.V., Hilden, Germany）. Usually the remaining two to align nucleotide sequencing and to construct a neighbor- legs were kept in a freezer at ‒30°C using a 99.5% ethanol joining（ NJ; Saitou and Nei, 1987） tree using p-distance. To soaked tube for further study of other regions of DNA. The leg estimate the confidence probability for each interior branch, the was homogenized in 200μl ATL-Buffer with 20μl proteinase K bootstrap method（ Felsenstein, 1985） was performed with 1,000 and incubated at 55°C over one hour. After incubation, total replications. genomic DNA was extracted following the manufacture’s Specimens from Ani-jima and Haha-jima Islands were obtained instructions. A DNA fragment of the mitochondrial cytochrome in the course of the following three research projects by the oxidase subunit I（ COI） gene was amplified using the Ministry of the Environment（ MOE）, Japan. They are “Research polymerase chain reaction（ PCR） with the primers LCO1490: for eradication of invasive lizard species, Anolis carolinensis on （5’-GGTCAACAAATCATAAAGATATTGG-3’） and HCO2198: Ani-jima Island”, “Research on countermeasures against A. （5’-TAAACTTCAGGGTGACCAAAAAATCA-3’）（ Folmer et carolinensis invasion on Ani-jima Island” and “Research on al., 1994）. PCR cycling condition were 94°C for 5 min, 35 cycles inhabitations of national endangered species on Haha-jima Acidon sugii sp. nov. from Ogasawara Isls. 55

Island group”. slightly excised below apex, the tip of the apex pointed; ground color dark brown or reddish brown, often tinged with purplish Material depositories and terminology brown, sparsely scattered with pale scales; interspaces of the Most specimens including the holotype will be deposited in the antemedial and postmedial lines darker than ground color; area Institute for Agro-Environmental Sciences, NARO（ NIAES）, outside submarginal line usually darker than area within it; Tsukuba and some paratypes will be deposited in the Ogasawara subbasal line blackish brown, sometimes almost absent; Subtropical Branch of Tokyo Metropolitan Agriculture and orbicular stigma white or blurred black; reniform stigma Forestry Research Center（ OSBTMAFRC）, Chichi-jima Island, inconspicuous, often with very small white point on the inner Ogasawara Islands. side, and sometimes a blurry black spot; postmedial line pale brown or yellowish brown, sinuously excurved, its outer area Morphological terminology of adult structures used in this paper often widely covered with pale scales; subterminal line follows Holloway（ 2008）, Lödl（ 1997; 1998; 1999） and Ueda represented by an irregular series of dark brown dots on （1984）. interspaces of veins or almost absent; cilia blackish brown with a series of whitish brown dots on veins; underside of forewing Results and Discussion with a conspicuous straight line at the middle. Hindwing: Morphological studies uniformly dull brown; cilia blackish brown with a series of whitish brown dots on veins; underside of hindwing with a Genus Acidon Hampson, 1896 conspicuous excurved line and a blackish brown spot. Acidon Hampson, 1896: 462 Female（ Figs 6-8, 10）. Forewing length 12.1-15.4 mm. Generally Type species: Acidon paradoxa, Hampson, 1896 by original similar to male, but labial palpi shorter than male, smoothly designation. porrect to four times length of the head; antenna filiform in female but bipectinate in male. Diagnosis Male genitalia（ Figs 11a, 11b）. Generally smaller and more weakly The genus often has a produced and falcate forewing apex. The sclerotized than its relatives. Uncus moderately long, tip pointed. male genitalia are generally broader and thinner than other Tegumen longer and more developed than vinculum, squarish- genera of the “Mecistoptera generic group”, and the valva shaped dorsally; vinculum slender, bulging dorsally; saccus usually has two slender processes（ saccular process and central nearly triangular. Valva rectangular and elongate with almost process sensu Holloway（ 2008）） which are weakly sclerotized straight ventral and dorsal margins, gradually broadened towards in comparison with the other close genera, Mecistoptera and a squarish apex; sacculus（ saccular process sensu Holloway Perciana. Additionally, the saccular process can be often absent. （2008）） sclerotized with an acute process at the middle; ampulla Holloway（ 2008） also mentioned that the ductus bursae of the （central process sensu Holloway（ 2008）） weakly sclerotized, female genitalia are more elongate than in Mecistoptera. In slender, reaching well beyond the center of the valva, slightly addition, this genus contains more diverse facies types than do incurved at the distal part which is clearly separated from the its close genera, Mecistoptera, Perciana and Hiaspis（ Holloway, valva. Aedeagus short and flexed obtusely near the middle, 2008）; for example the male has morphologically very diverse scobinate in the posterior ventral half; vesica generally slightly antennal structures, including ciliate, fasciculate and serrate. scobinate, without cornutus. Juxta rectangular, with an obvious Description longitudinal ridge in the middle. Acidon sugii Watabiki & Yoshimatsu sp. nov. Female genitalia（ Fig. 12）. Apophyses posteriores moderately ［Newly proposed Japanese name: Shimaisunoki-atsuba］ long. Apophyses anteriores very short. Ostium bursae Male（ Figs 3-5, 9）. Forewing length 12.3-16.0 mm. Head: labial sclerotized, concave at the middle of the posterior margin. palpi very long, smoothly porrect to five times length of the Ductus bursae almost sclerotized, constricted at the middle of head; second segment dark brown tinged with purple; third both sides. Corpus bursae ovate, produced into an angle on one segment almost half length of the second segment, dark brown side at the junction with the ductus; signum absent. tinged with purple in the anterior half, white on the posterior half Type materials. Holotype（ Fig. 3 ）: ♂, Mt. Chuo-zan, Chichi- and the tip; frons and vertex densely covered with purplish dark jima Island, Ogasawara Islands, Tokyo, Japan, larva collected on brown scales; antenna bipectinate. Thorax: tegulae purplish dark 11. Feb. 1996 and pupated on 18. Feb. 1996, emerged on 6. Mar. brown; fore-, mid-, hind-legs purplish dark brown with creamy 1996 , collected and reared by K. Takeuchi（ Depository: white band on marginal end of each segment of tarsus, mid-legs NIAES）. Paratypes: 4♂7♀, same locality as holotype, larvae with four spurs on tibiae, hind-legs with two spurs on tibiae. collected on 1-7. Jan. 1996 and pupated on 7-20. Jan. 1996, Abdomen: purplish dark brown. Forewing: termen of forewing emerged on 23. Jan.-5. Aug. 1996, collected and reared by K. 56 D. Watabiki et al.

Figs 3-10. Adults of Acidon sugii sp. nov.: 3 Holotype, ♂, Chichi-jima Island; 4-5 Paratype, ♂, Chichi-jima Island; 6-7 Ditto, ♀; 8 Paratype, ♀（LC159393）, Haha-jima Island; 9 Labial palpi, ♂; 10 Ditto, ♀. Acidon sugii sp. nov. from Ogasawara Isls. 57

Fig. 12. Female genitalia of Acidon sugii sp. nov. in ventral view. Scale bar = 0.5mm.

are unique in the “Mecistoptera generic group” and the male labial palpi are relatively longer than other species of the group. In addition, the ampulla（ central process sensu Holloway （2008）） of the male genitalia reaches well beyond the center of Fig. 11. Male genitalia of Acidon sugii sp. nov. （ a） left valva + the valva, and the aedeagus is short and centrally obtusely ring in ventral view,（ b） aedeagus in left lateral view, vesica flexed. everted. Scale bars = 0.5mm. During the study many non-target species were found on adhesive traps designed to capture the invading lizard species, Takeuchi; 2♂1♀, same locality as holotype, larvae collected on green anole, in the Ogasawara Islands and they included many 11. Feb. 1996 and pupated on 23-24. Feb. 1996, emerged on 15. unidentified species or new species（ Mita et al., 2015; Suguro Mar.-27. Aug. 1996, collected and reared by K. Takeuchi; 1♀, and Nagano, 2015）. same locality as holotype, larva collected on 2. May. 1996 and pupated on 13. May. 1996, emerged on 21. Oct. 1996, collected Habitat preference（ Fig. 13）. On Chichi-jima and Ani-jima and reared by K. Takeuchi; 1♀, Mt. Kasa-yama, Chichi-jima Islands, specimens were collected from the “Distylium dry Island, larva collected on 5. Apr. 1996 and pupated on 10. Apr. forest” sensu Shimizu（ 1992） whose vegetation is distributed 1996, emerged on 10. Sep. 1996, collected and reared by K. mainly at an altitude above 100m. Takeuchi; 1♂, Nagasaki, Chichi-jima Island, 25. Oct. 1995, at Etymology and comment on Japanese name. The specific name light, K. Takeuchi leg.; 2♂, Higashidaira, Chichi-jima Island, of this new species is dedicated to late Mr Shigero Sugi, who 27. Feb. 1996, Light Trap, I. Okochi leg.; 1♂, Mt. Mikaeri-yama, previously mentioned it as an unknown endemic species of the Ani-jima Island, 27. Jan. 2015, on adhesive trap, D. Watabiki leg., Ogasawara Islands in personal comments（ Takeuchi and （LC159392）; 2♀, Shin-yuhigaoka, Haha-jima Island, 8-9. Sep. Ohbayashi, 2006） and donated a lot of specimens to NIAES. 2012, Light Trap, JWRC leg.,（ LC159393, LC159394）. The Japanese name was referred to as “Shimaisu-atsuba” in All reared specimens were collected in the larval stage when Takeuchi and Ohbayashi（ 2006）, but this name was abbreviated feeding on Dystilium lepidotum Nakai. All paratypes of the new mistakenly from “Shimaisunoki-atsuba” which was proposed by species will be deposited in NIAES and OSBTMAFRC. the late Mr Shigero Sugi（ pers. comm., 1996）. Therefore, we use the latter instead of the former as mentioned above. Distribution. JAPAN: Ogasawara Islands（ Ani-jima, Chichi-jima and Haha-jima Islands） DNA experiments Host plant. Distylium lepidotum Nakai（ Hamamelidaceae） As shown in Fig. 14, we were able to obtain successfully the sequence data of a part of the mitochondrial DNA（ COI） genes Diagnosis and Remarks. The new species is similar to Acidon of this new species from one individual from Ani-jima Island calcicola Holloway from Borneo, but can be clearly distinguished and two specimens from Haha-jima Island. We recognized two on the male external structures. The bipectinate male antennae 58 D. Watabiki et al.

Fig. 13. Habitat of Acidon sugii sp. nov., near Mt. Mikaeri-yama, South Ani-jima Island, alt. 220m. Photo by D. Watabiki in June, 2014.

Fig. 14. Neighbor-joining tree of Acidon sugii sp. nov., Hepatica nakatanii Sugi and Perciana marmorea Walker based on 591bp of the mitochondrial COI gene. Thyas juno（ Dalman） was used as an outgroup species. The bootstrap method was performed with 1,000 replications. different haplotypes between the specimens from the Ani-jima relatives, Perciana marmorea and Hepatica nakatanii: these and Haha-jima islands with an approximately 1.0% average three species have approximately 6.2% interspecific sequence sequence divergence between them. But no morphological divergence value, a numerical value which is lower than the differences were observed between the specimens from the Ani- average interspecific value within congeneric species in jima and Haha-jima Islands. Lepidoptera, 7-8% as shown in Hebert et al.（ 2009）, Hausmann et al.（ 2011）. Interspecific average value within related species We were able to distinguish Acidon sugii sp. nov. from its close Acidon sugii sp. nov. from Ogasawara Isls. 59 of the genus Tiracola in the Noctuidae was 5.1%, as mentioned 1989: 1-22. in Watabiki and Yoshimatsu（ 2013）. On this basis, the molecular Kononenko, V.S. and B.A. Pinratana, 2013. of Thailand 3 , analysis data support the conclusion that the genera Acidon and Part 2. Noctuoidea: 624pp., Brothers of Saint Gabriel in Hepatica are close groups in Kononenko and Behounek（ 2009）, Thailand, Bangkok. Kononenko and Pinratana（ 2013） and Holloway（ 2008）. Lödl, M., 1997. Die systematische Stellung der Gattung However, Yoshimoto（ 2002） suggested that many species of the Mecistoptera Hampson, 1893（ Insecta: Lepidoptera: genus Hepatica might be better placed in Ananepa Hampson. It Noctuidae: Hypeninae）. Ann. des Naturhist. Mus. Wien 99B:, is clear that further comprehensive morphological and molecular 355-374. Acidon study of these genera will be necessary to establish the Lödl, M., 1998. Revision der Gattungen Hampson, 1896 und Hiaspis Walker,［ 1866］ 1865 subfam. comb. n.（ Lepidoptera: relationships between their species. Noctuidae: Hypeninae）. Quadrifina 1: 25-62. Lödl, M., 1999. Revision of the genus Perciana Walker, 1865 Acknowledgments （Lepidoptera: Noctuidae: Hypeninae）. Quadrifina 2: 145-172. We would like to express our heartfelt thanks to Messrs Naoki Mita, T., K. Watanabe, T. Kishimoto, 2015. Occurrence of Chrysis Amako and Shuzo Kishi（ Ogasawara Ranger Office for Nature boninensis Tsuneki（ Hymenoptera: Chrysididae） in Anijima Conservation, Ministry of the Environment, Japan）, Dr Island, the Ogasawara Islands, with description of the male. Jpn. J. Syst. Entomol 21 Mitsuhiko Toda, Messrs Akinobu Imamura, Hideyuki Chiba and . : 191-194. Saitou, N. and M. Nei, 1987. The neighbor-joining method: a new Kou Ashizawa（ Japan Wildlife Research Center, Tokyo）, for method for reconstructing phylogenetic trees. Mol. Biol. Evol. providing us opportunities to carry out this study. Thanks are 4: 406-425. also due to Mr Tatsumi Suguro（ Keio Yochisha Elementary Shimizu, Y., 1992. Origin of Distylium dry forest and occurrence of School, Tokyo） for offering us critical information and an endangered species in the Bonin Islands. Pac. Sci. 46: 179-196. important article for this study. We are grateful to late Mr Suguro, T. and H. Nagano, 2015. A new species of the genus Icius Shigero Sugi for the donation of his collection to NIAES and Ms （Araneae: Salticidae） from the Ogasawara Islands, Japan. Eri Tanaka（ NIAES） for her help with DNA experiments. We Acta Arachnol. 64: 91-95. also acknowledge Dr Toshiharu Mita（ Kyushu University） and Takahashi, H., K. Akita and M. Toda, 2014. 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科）（綿引大祐・吉松慎一・竹内浩二・大林隆司・永野 裕） も近縁な種であると考えられる．両種は外見上よく似てい るが，本種の雄は触角が両櫛歯状，下唇髭が頭部の 5 倍程 属 Acidon Hampson はインドからオーストラリア地域にか 度の長さを有するのに対し，A. calcicola を含む Acidon 属 けて 21 種（そのうち 2 種は雌しか知られていない正体不 の他の種は，雄の触角が繊毛状や毛束状であり，下唇髭は 明種）が知られ，Kononenko and Pinratana（2013）でいう 頭部の 2-4 倍程度の長さであることから容易に識別でき ところの “Mecistoptera generic group” に属する一群である． る．また，雄交尾器からも明瞭に識別できる． 本グループには Acidon 属のほか，Mecistoptera Hampson， Perciana Walker，Hiaspis Walker，Hepatica Staüdinger， 分布：小笠原諸島（兄島・父島・母島）． Coarica Moore，Ruttenstorferia Lödl，Lophomilia Warren の 寄主植物： マンサク科シマイスノキ（ Distylium lepidotum 7 属が含まれており，さらに Holloway（2008）は形態学的 Nakai） な研究から Gonoglasa Hampson も本グループに含めるべき との見解を示している．また，本グループは全世界でおよ 本種の兄島と母島から得られた 1 雄 2 雌の標本を用いた分 そ 600 種を含む大属である Hypena Schrank と近縁である 子遺伝学的な検討も行った結果，得られた分岐図と解析 ことから，ヤガ上科の中でも特に分類学的問題を抱えたグ データから，兄島と母島間においておよそ 1% の塩基置換 ループに属している．ヤガ上科の高次分類は今なお混沌と 率が確認された（Fig. 14）．また，チョウ目における同属 しており，本種を含む “Mecistoptera generic group” の種は， 内の種間のミトコンドリア DNA（ COI） 領域の平均塩基置 日本産蛾類標準図鑑 2（岸田，2011）に従うとヤガ科アツ 換率はおよそ 7～8％であるとされるほか（ Hebert et al., バ亜科とカギアツバ亜科にまたがって含まれる扱いとな 2009; Hausmann et al., 2011），ヤガ科ヨトウガ亜科 Tiracola る．ここでは最近の分子遺伝学的な研究である Zahiri et al. 属における近縁種の塩基置換率がおよそ 5.1％程度であっ （2012） に従いトモエガ科アツバ亜科として扱った．以下 たことが示されているが（ Watabiki and Yoshimatsu, 2013）， に本新種の特徴を示す． 今回分子遺伝学的解析を併せて行った Perciana marmorea Walker，ナンキシマアツバ Hepatica nakatanii Sugi, および Acidon sugii Watabiki & Yoshimatsu sp. nov. シマイスノキア 本新種の平均塩基置換率はおよそ 6.2％であり，属以上の ツバ（新称） レベルで一般的に見られるような大きな遺伝的差異は見ら 前翅長：♂ 12.3-16.0 mm, ♀ 12.1-15.4 mm. 雄の触角は両 れなかった． 櫛歯状で，下唇髭は非常に長く頭部の 5 倍程度の長さを有 本種は日本産ヤガ上科の分類学者であった故杉繁郎氏の助 する．雌の触角は糸状で，下唇髭は雄より短い．雌雄とも 言をもとに竹内・大林（2006）においてクルマアツバ亜科 に前後翅の色調は黒褐色から赤褐色で，前翅の内横線と外 の属名・種名の未決定種として初めてリストアップされた 横線の間および亜外縁線より外側は暗色になる傾向があ 種である．そこで本種の学名は杉繁郎氏に献名し，和名は り，個体によっては薄紫色の鱗粉を散布する．環状紋は通 杉氏が竹内と大林に書面上で提示していたもの（杉私信， 常白色あるいは黒色の点状であるが，大きな白色紋状とな 1996）と同様に，シマイスノキアツバとした．なお，竹内・ る個体もある．前後翅とも裏面には黒褐色線があり，後翅 大林（2006）では “ シマイスアツバ ” として扱われたが， はその内側に黒褐色紋を伴う． これは杉氏提案の和名を誤って略してしまったものである． 本種は日本における本属の初記録種で，交尾器の形態から ボルネオ島より記載された Acidon calcicola Holloway が最 （Received September 14, 2016. Accepted December 27, 2016）.