蝶と蛾 Science 67（3/4）: 89-98, December 2016

Pupal habits of four species of the subfamily Eublemminae feeding on dead leaves（ Lepidoptera, ） ―An analysis of pupal shelters made by larvae of Oruza yoshinoensis, Arasada ornata, Oruza glaucotorna and other close species ― Shintaro Funakoshi Beppu222-2, Mizuho, Gifu, 501-0222 Japan

Abstract Prior to forming a cocoon, the larvae of the species Oruza yoshinoensis（ Wileman）, Arasada ornata （Wileman）, Autoba tristalis（ Leech）, O. glaucotorna（ Hampson） and O. mira（ Butler） build elaborate shelters using dead leaves left on branches. I looked for shelters and larvae at a study site on Mt. Kinka in Gifu City, Japan. Larvae were then raised in plastic containers and allowed to make their shelters. Larvae of O. yoshinoensis, A. ornata and O. glaucotorna made very similar shelters despite differences in . There were subtle differences between the shelters that distinguished the three species. The shelter-making behaviors of these moth larvae appear to be as useful as morphological characteristics for species classification.

Key words Evolution, dead leaves on branches, leaf morphology, male genitalia, parasitism rate, shelter morphology.

Introduction with a lid. Kogi（ 2011） collected larvae of O. mira on dead leaves of Quercus dentata and described how they cut leaves to After trees of Castanopsis cuspidata（ Thunb.） Schottky and make their cocoon. The larvae of O. mira are slender and very Quercus glauca（ Thunb.） die, their leaves wither on the branch similar to the larvae of O. yoshinoensis, A. ornata and O. for several months before falling to the ground（ Figs 1-3）. The glaucotorna. I expected that the larvae of these four species larvae of several moth species specialize on these dead leaves would probably show similar behavior. Here, I compare shelter （Funakoshi, 2012, 2013, 2014）. Larvae of O. yoshinoensis（ Figs structures and the ecology of each species. I assumed that the 4-6）, A. ornata（ Figs 7-9） and O. glaucotorna（ Figs 10-12） are four species. O. yoshinoensis, A. ornata, O. glaucotorna and O. slender and have similar markings. There is a pair of red mira would be closely related based on morphological type and semicircular spots on the lateral abdominal segment A 2 in A. larval habit. ornata which are not present in the other species. The larvae of O. glaucotorna are distinguished by two dorsal lines that widen as they extend towards the ends of the segments. The larvae of A. Methods tristalis（ Figs 13-15） are slender and change morphology with Study site each larval instar, making identification easy. Yamamoto（ 1965） collected larvae of O. mira on dead leaves of Rhus javanica var. The felling of trees on Mt. Kinka（ elevation 329 m, 35.26°N chinensis and showed that they make a characteristic cocoon 136.26°E） located in Gifu city central Japan has been prohibited

Figs 1-3. A study site and dead branch. 1: Forest of Castanopsis cuspidata（ Thunb.） Schottky. 2: Dead branch of C. cuspidata 16 February 2014. 3: Same branch of C. cuspidata 6 July 2014. 90 S. Funakoshi

Figs 4-6. Oruza yoshinoensis（ Wileman）. 4: Last instar larva, dorsal view. 5: Ditto, lateral view. 6: Adult winged. Figs 7-9. Arasada ornata（ Wileman）. 7: Last instar larva, dorsal view. 8: Ditto, lateral view. 9: Adult winged. Figs 10-12. Oruza glaucotorna Hampson. 10: Last instar larva, dorsal view. 11: Ditto, lateral view. 12: Adult winged. Figs 13-15. Autoba tristalis（ Leech）. 13: Last instar larva, dorsal view. 14: Ditto, lateral view. 15: Adult winged. for about 400 years from the Edo period. There is a climax （diameter 73 mm, height 82 mm）. A piece of moistened filter community of C. cuspidata and other vegetation such as Q. paper was placed on the wall of the container to maintain glauca, Cleyera japonica, Camellia japonica, Photinia glabra, humidity levels. The paper was changed every day when Pieris japonica, Maesa japonica, Pyrrosia lingua, etc. excrement was removed. Approximately twenty dead leaves of C. cuspidata were added to each container（ Fig. 16）. Leaves Collected and raised larvae were of various sizes not scarred and still attached to a branch. I collected shelters and larvae of O. yoshinoensis, A. ornata, O. The branch with the leaves was positioned upwards. The length glaucotorna, O. mira and A. tristalis. Early instar larvae were of the leaf, whether the shelter was on the adaxial or abaxial raised in a film container（ diameter 30 mm, height 51 mm）. Late surface of the leaf, shelter position on the leaf, shelter length, the instar larvae were transferred to a large plastic container direction the leaf was bent to make the shelter, the direction of Pupal habits of Eublemminae on dead leaves 91

（Fig. 29）. To make their shelters, the mature larvae drew circles on two parts of a dead leaf and then made cuts to the leaf edge. Both ends of the cylinder were then made into lids. Silk thread was spread roughly inside the shelter. The pupa secured itself with crockets of setae in the silk thread on or around the lid. The adult lifted the other lid like a door upon eclosion. Thirty-two shelters were collected at the study site. Twenty-nine were those of O. yoshinoensis, five of which eclosed. The others Fig.16. Raising last instar larva with were parasitized. One shelter was made by A. ornata, from twenty dead leaves of C. cuspidata. which an adult male later emerged. I did not find any O. glaucotorna shelters. Identification of the remaining two shelters eclosion from the shelter, and adult wing length were recorded. was impossible because the pupal shells were lost. Eighty-four When pupae failed to emerge, the shelter was opened and O. yoshinoensis, 31 A. ornata and 41 O. glaucotorna made checked to determine the direction of eclosion and the sex.The shelters in containers. Shelter length, adult wing length, and leaf genitalias of adults of three of the species were examined length were measured（ Table 1 ）. The percentage of parasitism microscopically to compare the morphology. was low for individuals raised from early instars, and many individuals emerged（ Fig. 30）. Almost all shelters of O. Results yoshinoensis found in the study site were made on the adaxial surface of the leaf, whereas some larvae reared in containers Adult wing lengths and shelter lengths were modestly different made their shelters on the abaxial surface of the leaf. Many A. among species（ Table 1）. Adult wing lengths of O. yoshinoensis ornata and O. glaucotorna reared in containers made their and A. ornata were significantly different （ t-test；P<0.05, t = shelters on the abaxial surface of the leaf（ Fig. 31）. Except for 2.963, df = 47 ）, but those of A. ornata and O. glaucotorna were O. glaucotorna, most shelters were positioned in the center of not significantly different（ t-test；P>0.05, t = 1 . 181 , df = 61）. leaves（ Fig. 32）. No trend was observed in leaf cutting direction Shelter lengths of O. yoshinoensis and O. glaucotorna were （left to right, right to left）, but top to bottom appeared only in significantly different（ t-test；P<0.05, t = 6.744, df = 52）, but those the making of O. yoshinoensis shelters（ Fig. 33）. The correlation of A. ornata and O. glaucotorna were not significantly different between cutting direction and leaf surface was not significant （t-test；P>0.05, t = 1.248, df = 70）. The shelter morphologies of O. （Table 2）. yoshinoensis, A. ornata and O. glaucotorna were very similar. It was not possible to distinguish the three species by the appearance At the study site, adults always escaped from the bottom of of their shelters made on C. cuspidata（ Figs 17 - 22）. Autoba shelters. Although emergence from the bottom was more tristalis shelters were easily identified by their structure（ Figs 23, common in containers, adults also emerged from the top, left and 24）. right（ Fig. 34）. Some reared individuals made shelters in a leaf with a feeding scar; therefore, the leaf length could not be Most of the shelters collected at the study site were parasitized measured. There were differences of correlation between shelter （Figs 25, 26）. The species to which the pupae belonged could length and leaf length: low positive correlation in O. be identified by examining the cremasters still present in the yoshinoensis（ Pearson correlation coefficient, r= 0.2151 shelters: three pairs of fat hook setae on the top and three pairs individuals collected in the field, r= 0.2875）, low negative of slender setae on the side in O. yoshinoensis（ Fig. 27）; two correlation in A. ornata（ r=－0.2609） and low positive pairs of fat setae and one pair of slender setae on the protruding correlation in O. glaucotorna（ r=0.3791; Figs 35-38）. There was part in A. ornata（ Fig. 28）; one pair of fat setae on the center a positive correlation between shelter length and adult wing part and two pairs of slender setae on the side in O. glaucotorna length in O. yoshinoensis（ Pearson correlation coefficient,

Table 1. Shelter length, adult wing length, and leaf length of 3 species.

O. yoshinoensis A. ornata O. glaucotorna

Field（ n） Room（ n） Field（ n） Room（ n） Field（ n） Room（ n）

Length of wings 20.38（ 4） 18.90 ± 1.41（ 73） 21.67（ 1） 20.12 ± 2.24（ 30） 22.44（ 1） 20.71 ± 1.57（ 33） Length of shelter 17.43 ± 1.29（ 32） 15.64 ± 1.36（ 84） 20.57（ 1） 19.15 ± 2.02（ 31） ― 18.49 ± 2.53（ 41） Length of leaf 59.68 ± 10.00（ 31） 67.59 ± 13.99（ 69） 58（ 1） 71.44 ± 12.80（ 28） ― 91.61 ± 14.99（ 34） 92 S. Funakoshi

Figs 17-18. Shelter made of cutting dead leaf by larva of O. yoshinoensis. 17: External. 18: Internal. Figs 19-20. Shelter made of cutting dead leaf by larva of A. ornata. 19: External. 20: Internal. Figs 21-22. Shelter of cutting dead leaf made by larva of O. glaucotorna. 21: External. 22: Internal. Figs 23-24. Shelter of cutting dead leaf made by larva of A. tristalis. 23: External. 24: Internal. Fig. 25. Shelter collected from a study site. Fig. 26. Shelter parasited by ichneumon wasp.

Figs 27-29. Cremasters. 27: O. yoshinoensis. 28: A. ornata. 29: O. glaucotorna.

Table 2. Correlation between cutting direction and leaf surface. O. yoshinoensis in field O. yoshinoensis A. ornata O. glaucotorna adaxial abaxial adaxial abaxial adaxial abaxial adaxial abaxial left → right 16 3 34 9 8 8 1 19 right → left 12 1 32 9 9 6 1 20 d.f. 1 1 1 1 p 0.2099 0.8055 0.5572 0.8728 χ2 1.5714 0.0606 0.3445 0.0256 Pupal habits of Eublemminae on dead leaves 93

Fig. 30. Rate of individuals of wings, parasite and prey. Fig. 31. Rate of shelters formed on the adaxial or abaxial surface of leaves. Fig. 32. Rate of shelters formed on the 3 divided place of leaves. Fig. 33. Rate of shelters formed in the directions of toward. Fig. 34. Rate of direction of adults’ appearance. 94 S. Funakoshi r=0.6070）, A. ornata（ r=0.8991 and O. glaucotorna（ r=0.4787; attempted to classify species based on the shape and function of Figs 39-41）. Larvae parasitized by parasitic wasps and parasitic the shelter（ Greeney and Jones, 2003 ; Greeney, 2009）. The flies made shelters. The larvae of O. yoshinoensis, A. ornata and methods of making shelters and their shape have been discussed O. glaucotorna elaborately processed dead leaves to form their from an evolutionary perspective（ Greeney et al., 2010）. shelters, whereas the larvae of A. tristalis bent one side of a leaf, The frequent appearance of shelter making behavior makes cut it into a half-ellipse, and left it. Five larvae of O. glaucotorna evolutionary sense. As the frequency of parasitism on O. were collected from dead leaves of C. cuspidata at the study site, yoshinoensis in the late instar and pupal stages increases, so and only one of them made a shelter. In contrast, 36 larvae of O. should it increase for A. ornata and O. glaucotorna. Almost all glaucotorna were collected on the dead leaves of C. japonica. larvae of O. yoshinoensis make shelters on the adaxial surface of When dead leaves of C. cuspidata and C. japonica were offered the leaf in the field, so it may be easier to bend the leaf from the to mature larvae, 7 larvae moved to the C. cuspidata leaf and adaxial surface than from the abaxial surface. Though many formed a shelter. Only one larva of O. mira was collected from a larvae of O. yoshinoensis make their shelters on the adaxial Quercus glauca leaf near the study site. surface, many larvae of A. ornata and O. glaucotorna make The morphology of the genitalia of A. ornata was different from theirs on the abaxial surface. Leaf selection of larvae of the three those of O. yoshinoensis and O. glaucotorna in aspects such as species may be different in the field. Positioning the shelter in chitinization, asymmetry and difficulty of opening of the valvae the center of the leaf may provide stability on the small leaf of C. （Figs 42-50）. cuspidata. On the other hand, many larvae of O. glaucotorna may select the top of the leaf because C. japonica leaves are Discussion larger and curled. The direction of shelter formation by O. glaucotorna was different from that by O. yoshinoensis and A. It is known that the larvae of many lepidopteran species make ornata. This is the reason for the correlation between tree and shelters to protect themselves from predation and competition leaf characteristics. As the shelters seen in the field were made for habitat（ Loeffler, 1996）. In many instances, the shelter is on leaves that had few food scars, it was thought that mature made with a leaf outside the cocoon（ Holloway, 2009）. Other larvae moved to a new leaf and made a shelter on this leaf. A also use the shelters made by lepidopterans to protect leafstalk of dead leaves left on a fallen tree would almost always themselves（ Kudo, 1994 ; Nakamura and Ohgushi, 2003）. It is be on the top. Adults emerged and moved upwards towards the also known that shelter-making behavior depends on the larval leafstalk. Many larvae of O. glaucotorna were collected from et al stage and the size of the leaf（ Abarca ., 2014）. Some have the remaining dead C. japonica leaves. Dead leaves of C.

Figs 35-38. Relationship of length of shelter and leaf. 35: O. yoshinoensis. 36: O. yoshinoensis in the field. 37: A. ornata. 38: O. glaucotorna. Pupal habits of Eublemminae on dead leaves 95

Figs 39-41. Relationship of length of shelter and wing in O. yoshinoensis. 39: O. yoshinoensis. 40: A. ornata. 41: O. glaucotorna.

Figs 42-50. Genitarias of three species of Eublemminae. 42-44: O. yoshinoensis male, lateral view, female. 45-47: A. ornata male, lateral view, female. 48-50: O. glaucotorna male, lateral view, female. 96 S. Funakoshi

Fig. 51. Two pattern models thought on shelter formation. japonica wither up into a ball along the abaxial surface of the shelter construction behavior is lost, the intervening stages of its leaf. O. glaucotorna is unique in that it builds its shelters on construction may be found in pattern（ A）. I cannot think of any dead C. japonica leaves, whereas larvae of other species may other part of the moth phylogeny where the direction of move to other trees. Shelters made by larvae of O. yoshinoensis, evolution is split and yet the larvae construct a complicated A. ornata and O. glaucotorna are almost identical in appearance, structure that is so similar（ B）. I thought elucidation of the but can be distinguished by examining the shelters in detail. living history of these genera was important to compare the shelter construction of the larva. O. yoshinoensis was first identified as Corgatha, but was later moved by Sugi and Owada（ 1982） to Oruza. A. ornata was classified by Hampson（ 1910）, but it was also indicated that Acknowledgments further consideration was warranted（ Sugi and Owada, 1982）. I wish to express cordial thanks to Prof Furumi Komai of Osaka The former classification was based on the adult form University of Arts for reading the manuscript and for his advice （Holloway, 2009）. A. ornata seemed different from the other on production of a document and larval habits. 2 species in the morphology of the genitalia in respect of chitinization, asymmetry and difficulty of opening of valvae. References Mention of the larval form of O. mira appears in only a few Abarca, Ｍ., K. Boege and A. Zaldivar-Riveron, 2014. Shelter- studies（ Yamamoto, 1965 ; Kogi, 2011）. Holloway（ 2009） building behavior and natural history of two pyralid caterpillars illustrated a larva of Arasada albicosta（ Hampson） cutting off a feeding on Piper stipulaceum. J. Sci. 39: 1-16. cylindrical piece of Calamus（ Palmae） leaf and then pupating in Funakoshi, S., 2012. Moth larvae feeding Castanopsis cuspidata it. He pointed out that this behavior was very similar to that of （II）; the first records of larvae of Oruza yoshinoensis Cerynea punctilinealis（ Walker） and Metaemene. （Wileman） and Paracolax bilineata（ Wileman）（ Noctuidae）. Japan Heterocerists’J.（ 263）: 321-325. Here, species of the same genera did not display all the same Funakoshi, S., 2013. Moth larvae feeding Castanopsis cuspidata behaviors, but the four Eublemminae species studied did （III）; the first records of larvae of Autoba tristalis（ Leech） construct nearly identical shelters upon pupation, even though （Noctuidae）. Japan Heterocerists’ J.（ 267）: 430-437. they are classified into different genera. Moreover, when Funakoshi, S., 2014. Moth larvae feeding Castanopsis cuspidata considering the relationship between species and shelter structure, （IV）; the first records of larvae of Arasada ornata（ Wileman）, there appeared to be two patterns（ A and B; Fig. 51）. Even as Oruza glaucotorna Hampson, Edessena gentiusalis Walker and Pupal habits of Eublemminae on dead leaves 97

Paracolax sugii Owada（ Noctuidae）. Japan Heterocerists’ J. とで区別される．A. tristalis は，斑紋が成長段階で変化し （270）: 512-518. て前 3 種との区別は容易である．飼育容器には枝についた Greeney, H. F., 2009. A revised classification scheme for larval ままの食痕の無いさまざまな大きさのツブラジイ枯葉を hesperidia shelters, with comments on shelter diversity in the 20 枚ほど与えてシェルターを造らせた．O. glaucotorna は， Pyrginae. J. Res. Lepid. 41: 53-59. サカキの枯葉から多くの幼虫が得られたので，サカキの枯 Greeney, H. F. and M. T. Jones, 2003. Shelter building in the 葉も与えた．これらの種のシェルター形成の違いを調べる Hesperidia: a classification scheme for larval shelters. J. Res. ため，シェルターを造った葉の葉身長，葉の表裏，葉上の Lepid. 37: 27-36. 位置，切り込みを入れて折り返す方向，羽化後のシェルター Greeney, H. F., R. W. Walla and R. L. Lynch, 2010. Architectural からの脱出方向などを調べた．枯葉は葉柄が上になってい changes in larval leaf shelters of Noctuana haematospila るが，葉の位置，方向の記録は葉端を上とした．一部のも （Lepidoptera: Hesperiidae） between host plant species with のはシェルターを開き，蛹あるいは羽化後の蛹殻より種お different leaf thicknesses. Zoologia 27: 65-69. よび性と脱出方向を確認した．羽化後および寄生された蛹 Hampson, G. F., 1910. Catalogue of Lepidoptera Phalaenae in the 殻などの同定は，尾突起の形態で行った． British Museum. Vol.10: i-xix, 1-829. Holloway, J. D., 2009. The of Borneo. Part 13 Noctuidae. 寄生率は，採取された未成熟幼虫の多くが羽化したことか Malay. Nat. J. 62（1and 2）: 1-124. ら，成熟幼虫および蛹期に高くなると推定された．野外で Kudo, S., 1994. Observations on Lepidopteran last-shelters as 得た O. yoshinoensis のシェルターは，一部が葉の裏に作ら molting refuges for the sting bug Elasmucha putoni れていたが，飼育した同種幼虫のシェルターは，裏面に作 （Heteroptera；Acanthosomatidae）. Psyche 101: 183-186. られるものが多くなった．A. ornata や O. glaucotorna の飼 Kogi, H., 2011. Moths feeding on Quercus dentate Thunb, as larvae 育個体は裏面に作るものがさらに多く，O. yoshinoensis と in Hokkaido 26. Japan Heterocerists’J.（ 260）: 238-241. の違いが認められた．シェルターを造る葉の位置，折り曲 Loeffler, C. C., 1996. Caterpillar leaf folding as a defense against げる方向，成虫の脱出方向は，3 種とも共通しており，種 predation and dislodgment: staged encounters using Dichomeris ごとの違いを見いだすことができなかった．また，いずれ （Gelechiidae） larvae on goldenrods. J. Lepid. Soc. 50（3）: の種においても折り曲げる方向と葉の表裏との関係に有意 245-260. な差は認められなかった．シェルター長と葉身長との関係 Nakamura, M. and T. Ohgushi, 2003 . Positive and negative effects は，3 種に違いが見られた．O. yoshinoensis は，室内でシェ of leaf shelters on herbivorous insects: linking multiple ルターを造ったものも野外で得られたものもともに低い相 herbivore species on a willow. Oecologia 136: 445-449. A. ornata O. glaucotorna Sugi, S. and M. Owada, 1982. Noctuidae. In Inoue H. et al（. eds）, 関があり， は低い負の相関があり， Moths of Japan 1: 669-935, 2: 344-408, pls. 164-226. は低い相関があった．シェルター長と成虫開張との関係は， Yamamoto, Y., 1965. Noctuidae. In Mutuura A. et al.（ eds）, Early 3 種とも相関があり , 中でも A. ornata には高い相関があっ stages of Japanese moths in colour I, Pp. 61-166, pls. 20-55. た．また，野外で得られたシェルターは，ほとんど食痕の ない葉に造られており，成熟幼虫は新たな葉に移動して シェルターを作成すると考えられた．羽化個体の多くが葉 摘 要 の下方向から脱出することは，葉柄が上になる倒木に残っ 枯葉を食するベニコヤガ亜科 4 種のシェルター形成 －ヨ た枯葉においては上に向かうことになり，翅の展開や飛翔 シノクルマコヤガ，ヤマトコヤガ，モンシロクルマコヤガ に有利になると思われた．O. glaucotorna の幼虫は，枯れ の幼虫が形成する蛹化シェルターの分析－（船越進太郎） ると葉が縦方向裏側に丸まってしまうサカキの中におり， ベニコヤガ亜科 Eublemminae のヨシノクルマコヤガ Oruza 枯葉の構造上，葉を切ってシェルターを造る行動は裏側で yoshinoensis，モンシロクルマコヤガ O. glaucotorna, ヤマト 可能となる．しかし，ツブラジイの枯葉を与えるとその表 O. glaucotorna コヤガ Arasada ornata，ツマトビコヤガ Autoba tristalis の 側にシェルターを造るものがいた． は，シェ 形態やシェルター形成の違いを調べた．これら 4 種の幼虫 ルターを形成するとき他の樹木の枯葉に移動するものがあ は，シイやカシの倒木の枝に残されている枯葉を食し，そ るのかも知れない． の葉を利用して蛹化のためのシェルターをつくる．A. マエヘリクルマコヤガ Oruza mira は，蛹化時に枯葉を切っ tristalis 以外の 3 種の幼虫は枯葉の 2 箇所に切れ込みを入 て特徴的な巣を造ることが明らかにされた（山本, 1965, 小 れて折りたたむように葉を重ね，両側に蓋をしてシェル 木 2011）． O. yoshinoensis，A. ornata，O. glaucotorna の 3 種 ターを完成させる． は，O. mira と同様の習性を有する．また，O. mira 幼虫は， O. yoshinoensis A. ornata 岐阜市金華山およびその周辺で 4 種の蛹化時に形成された と によく似た体型や斑紋であった． シェルターを探 すとともに，幼虫を採 集した． O. yoshinoensis， 幼虫の形態や習性をみる限りこれら 4 種は，近い種である O. yoshinoensis Corgatha O. glaucotorna，A. ornata の老熟幼虫は，斑紋がよく似て と考えられた． は， として記載さ Oruza いる．A. ornata には第 2 腹節背面に 1 対の赤い半球状模様 れた種であったが，杉ほか（1982） によって に移さ A. ornata があり，O. yoshinoensis や O. glaucotorna では認められない． れた． は，Hampton の検索表に従って分類されたが， O. glaucotorna の斑紋は，2 列の背線が各節後部で広がるこ なお検討の余地があるとされた（杉ほか 1982）． こ れ ま で の分類は成虫の形態で行われている（Holloway 2009）． 交 98 S. Funakoshi

尾器をみると A. ornata は他の 2 種よりもよりキチン化が発 分岐したそれぞれにシェルター形成を維持する集団と消失 達し，雄交尾器のバルバが左右非対称で開きにくいなど異 した集団が残った．B は先に形態分化が起こり，その中で なる点が多いように思われた．Oruza 属の幼虫形態は，O. 収斂的に共通のシェルターを形成する集団が生じた．とす mira の記載が唯一のようである（山本ほか 1965，小木 るものである．シェルター構造の複雑さから，B のパター 2011）． Holloway（2009）は ， Arasada albicosta の幼虫が蛹 ンは起こりそうではない．また，A のパターンでは，シェ 化時にヤシ科（Palmae）Calamus 属の葉をシリンダー状に ルター形成を消失する途中段階のものが見つかってもよさそ 切り取ってその中で蛹になることを図示し，よく似た習性 うである．O. yoshinoensis，A. ornata，O. glaucotorna, O. mira が Cerynea punctilinealis や Metaemene などでも見られるこ の 4 種は，はじめからシェルターを造るグループであったの とを指摘している．シェルターを造る習性から進化の道筋 かも知れない． を 2 通り考えた．すなわち，A はシェルターを造る祖先種 があり，形態分化が起きて 2 つの属に分かれた．その後， （Received November 24, 2015. Accepted August 19, 2016）