2001年4月から10月にかけて, 東京都武蔵野地域にある2つの都市公園において, トランセクト法によるチョウ類の調査を行った. 在来の環境を自然観察園として取り込んでいる野川公園では27回の調査によって7科35種1489個体, 広場を主体とした小金井公園では26回の調査によって7科25種942個体のチョウを観察した. 両公園に共通した優占種はヤマトシジミとスジグロシロチョウであった. 樹液依存性のタテハチョウとササ食のジャノメチョウおよびセセリチョウ科のチョウは野川公園, モンシロチョウ, モンキチョウなどの草原性のチョウは小金井公園において多く目撃された. 階級存在比の算定によって野川公園は二次段階, 小金井公園は都市段階と判定された. 大阪近郊の都市公園での調査結果との比較によって, 階級存在比の類似性は定量的類似度指数 (PIANKAのα指数) が示すチョウ類群集の類似性と必ずしも関連しないこと, およびスジグロシロチョウは武蔵野地域の都市公園を特徴付ける種であることが明らかになった.

抄録全体を表示

Tirumala limniace and T. septentrionis, migrant danaines, fly over to Japan every year from the further south. In the summer of 1995, numerous T. limniace and a few T. septenrionis arrived at Amami-ohshima Isl., and aggregated together with Ideopsis similis, a resident danaine there. Although their overwintering aggregations in their residential regions (e.g. Taiwan) have been reported, "aestivating aggregations" have little been noted. The present paper reports such a case and describes the behavior of the aggregated butterflies during the hot season at their northern temporary residence (Amami-ohshima). 1. From 4 July to 2 September in 1995, the migrant Tirumala limniace and T. septentrionis and the resident Ideopsis similis were observed forming an aggregation at the northern part of Amami-ohshima. 2. The two migrant species were collected as specimens (i. e. removed; 253 [160 ♂ ♂ 93 ♀ ♀] of T, limniace and 4 ♂ ♂ of T. septentrionis in total) almost every day by one of the authors, while none of I. similis, which was as numerous as T. llimiace, was removed, 3. They showed routine behaviors daily-visiting flowers or mating in the cool hours of early morning and late afternoon, but resting during the hot hours around midday. The weather in July-September was mostly sunny or cloudy (sometimes with showers) with the highest temperature over 30℃ , and no typhoon came in the study season. 4. Their habitats consisted of two sites, wooded areas for resting and flower beds for feeding. In late July they moved from the first site (station A) to the second site (station B) distanced about 30m from the former. 5. They mostly rested on some aerial roots of Ficus microcarpa and F. elastica (Moraceae) or small twigs of Jatropha hastata (Euphorbiaceae). Usually T. limniace rested higher than /. similis in position. 6. Nectar source flowers were Euphorbia milii var. splendens and Jatropha hastata (Euphorbiaceae). 7. Ten pairs of T. limniace in copula were observed in the field. The presence of spermatophore examined by fingers indicated most T. limniace females were fertile already. Due to the absence of foodplants, however, oviposition did not occur. On the other hand, despite of the presence of foodplant (Tylophora tanakae), I. similis did not lay their eggs there either. 8. Why did they make such a notable aggregation in 1995 at Amami-ohshima? The arrival of such an unusual large number (over 280) of T. limniace is likely to have been the fundamental cause. Although from April to July of the year, remarkable numbers of migrant or visiting butterflies, including newly recorded species in Japan, flew to the Nansei Islands from the Asian continent, Taiwan, and the Philippines, the number of T. limniace on Amami-ohshima was outstanding. 9. The departure site of the two species of Tirumala is inferred to be somewhere in Taiwan for two reasons. (1) The T. limniace was identified as ssp. limniace Cramer distributed in Taiwan and the Asian continent, but not as ssp. orestilla Fruhstorfer found in Luzon Isl. The T. septentrionis, which is not distributes in Luzon Isl., was ssp. septentrionis Butler occuring in Taiwan and the Asian continent. (2) The two Tirumala species are common in Taiwan in June and July together with the Chestnut Tiger (Parantica sit a), which is confirmed to migrate to Japan by markrelease-recapture method . The two Tirumala species are often found together with the Chestnut Tiger at their arrival sites in Japan. 10. In conjunction with other records of migrant butterflies in Japan, the two Tirumala species likely arrived at Amami-ohshima in the end of June, and move northward to reach the northern region of the island. Then they aggregated at this site to spend the hot summer days. In addition, possibly they were attracted by Ideopsis similis, which had aggregated there as precedent visitors. 11. One female of T. limniace bred in cage to obtain eggs lived for

(View PDF for the rest of the abstract.)

抄録全体を表示

Male germ-line chromosomes are examined in nine species of Poritiinae, Cyaniriodes libna, Poritia erycinoides, P. sumatrae, P. promula, P. hewitsoni, P. phormedon, Simiskina pharyge, Deramas livens and D. jasoda, in spermatogonium, primary and secondary spermatocytes. These chromosome numbers are as follows: C. libna 2n=74, n=37-38; P. sumatrae 2n=36, n=18; P. promula 2n=32, n=16; P. hewitsoni 2n=38, n=19; P. phormedon 2n=34, n=17. In particular, remarkable variations of chromosome numbers are observed in the following species: P. erycinoides 2n=36-44, n=18-22; S. pharyge 2n=72-74, n=36-39; D. livens 2n=36-44, n=18-25; D. jasoda 2n=96-102, n=48. Possible implications of the results are briefly discussed from an evolutionary point of view.

抄録全体を表示

研究では蛹化,羽化には体内時計が関係していると考え、明暗周期を変えた場合も蛹化,羽化が正常の時期に行われると仮説を立てた。実験は1〜5齢幼虫を用い、餌の量は一定にし、恒明条件(24L0D・蛍光灯を利用・室温25℃一定),恒暗条件(0L24D・室温25℃一定),屋外《4〜5月》13.5L10.5D・平均気温16.5℃・気温差平均9.5℃,《6〜7月》14.5L9.5D・平均気温25.2℃・気温差平均6.3℃で行った。結果は、どの条件でも通常に蛹化,羽化した。このことから、蛹化,羽化は体内時計によるものであると考えた。一方で、《4〜5月》、《6〜7月》の時期に屋外で飼育していた幼虫には、蛹の期間に違いが確認され、《4〜5月》では約14日,《6〜7月》では約6日であった。なお、越冬して5月に羽化した個体は白化型、7月以降に羽化した成虫は通常型であった。これより、白化型、通常型では、蛹の期間に違いがある事が分かった。また、羽化した個体の赤紋濃淡は多少の色の違いがみられた。そのため、色の違いを主観で分類せず数値化を試みた。これにはまず、所有する80個体の標本について照度一定条件で赤紋のRGB値の解析を行った。解析では、G値やB値とR値の比較、またアカボシゴマダラの幼虫時の生育環境、野外採集個体と赤紋濃淡の変化を比較した。すると、解析した80個体が大きく4グループに分類されることがわかった。さらに、生育環境の違いが赤紋濃淡に影響を及ぼさないことも示唆された。次に、従来は主観に基づいて行っていた赤紋濃淡の分類と、解析結果に基づく分類の比較を行った。これにより、感覚での分類と大きな差がなかったことがわかったが、同時にあいまいな判断を行っていた個体の分類が正確に行えるようになった。今後は、赤紋濃淡を生み出す要因の追求について検証を重ね、判断基準をより正確なものにしていきたい。

抄録全体を表示

A nymphalid butterfly Hestina assimilis assimilis, which was recently discovered in Kanagawa prefecture in Japan, undergoes larval diapause and show a seasonal change in wing color pattern: summer and spring (white) morphs. In the present study, temperature and photoperiodic conditions responsible for the control of seasonal morph determination was investigated. First, when post-diapause larvae were reared under various temperatures (15℃, 20℃, 25℃ or 28℃) at a long photoperiod (16L-8D), most of the eclosed adults were of white morph (spring morph). Second, larvae were initially exposed to a short photoperiod (10L-14D), and then transferred to 16L-8D to avoid diapause occurrence. Resulting adults were white morph. Third, individuals were reared at various temperatures (15, 20 or 25℃) under a long photoperiod (16L-8D) through larval and pupal stages. Low temperatures of 15℃ were quite effective for white morph production, but moderate (20℃) or high (25℃) temperatures were not effective, and all butterflies produced developed black veins on the wing (summer morph). Fourth, in experiments where different rearing temperatures were combined during the larval life, a temperature of 15℃ combined with 20℃, but not with 25℃, was effective for producing some intermediate or white morphs. Fifth, the temperature-sensitive stage for white morph production was mostly located in the 3rd and 4th instars (in partiular, 4th instar). In these experiments, white morph production was closely linked with extremely delayed larval development. The results strongly suggest that not only a short photoperiod, but also a relatively cool temperature including 15℃ is quite effective for white morph production even without an intervening larval diapause. Probably, an unknown neuro-endocrine mechanism may be responsible for the seasonal morph regulation as in the case of other butterfly species.

抄録全体を表示

従来,近畿地方以西に分布していたムラサキツバメは,近年,関東地方のほぼ全域で発生している.現段階での本種の定着北限に近いと考えられる関東地方北部において,2002〜2003年に野外における発生経過と幼生期の捕食寄生者および随伴するアリ類について調査した.1.野外における成虫・卵・幼虫の個体数調査の結果から,茨城県つくば市では,本種は部分4化であることが示唆された.第二〜第四世代の卵数のピークは,それぞれ6月下旬〜7月上旬,8月下旬,9月中旬であった.また第一世代に相当すると思われる卵が4月上旬に発見された.2.これまで,本種は4齢幼虫が終齢であるとされていたが,飼育観察と野外で採集された幼虫の頭幅の測定結果から,蛹化するまでに5齢を経過することが明らかとなった.3.幼虫あるいは蛹化後の蛹には,7種のアリ類が随伴していた.4,本種の卵期における捕食寄生者はこれまでに報告されていなかったが,本研究によって少ないながら卵が寄生されていることが明らかになった.また,幼虫期の寄生は確認できず,蛹期の寄生も数例のみに限られた.

抄録全体を表示

ブータンから中国南部,インドシナに分布するAemona属のamathusia,lenaの再検討をおこなった.タイプ標本を含む各地の個体を比較検討したところ,同一地域において地色や斑紋には変異があることが判明した.A.amathusiaではtonkinensisとcochinensisは原名亜種の同物異名(synonym)として処理した.A.lenaではhaynei,kalawrica,karennia,kentunga,salweenaは原名亜種の同物異名(synonym)として処理した.また両種の交尾器の比較を行なった.基本的構造は同じで,uncusに差異がみられた程度であった.Allaemona prasopsuki gen.&sp.nov.ミャンマー北部で発見されたAemonaに近縁な新属,新種の記載を行なった.新属の設立にはTalbot(1947)の分類体系に従い,翅脈相などから近縁と考えられたAemona,Faunis,Xanthotaeniaとの比較を行なった.その結果,もっともAemonaに近縁であることが判明したが,翅脈相,パルピ,交尾器,翅斑などが異なり,新属新種と判断した.

抄録全体を表示

In the 7th and final part of this series, we added 3 species of Papilionidae, 1 species of Pieridae, 10 species of Nymphalidae, 5 species of Satyridae, 6 species of Riodinidae, 30 species of Lycaenidae, and 12 specie of Hesperiidae. Niphanda asialis, Jamides cyta, Catopyrops ancyra, Arhopala phanda, Rapala damona, and Coladenia indrani are new to Vietnam. In this series, 664 species of butterflies of southern part of Vietnam are confirmed and illustrated with some comments in Japanese. Ten new species and 3 new subspecies in addition to 30 new records from Vietnam are obtained in our surveys. A careful examination of the male genitalia indicates that we misidentified Callenya melaena as Callenya lenya and Jamides pura as Jamides zebra in the series 4 (no.211).

抄録全体を表示

Eggs, larvae and pupae of Narathura bazalus (Ibaraki population) were reared at 17, 20, 23, 25 and 28℃ under long-day (LD 15:9) or short-day (LD 12:12) conditions. Egg periods were 6, 5 and 4 days at 20, 23 and 25℃, respectively. The developmental zero and the total effective temperature for egg development (from oviposition to egg-hatch) were 11.0℃ and 54.7 degree-days, respectively. Photoperiod affected the development of larvae and pupae. Under long-day condition, the average periods from egg-hatch to adult emergence were 64, 47, 36, 30 and 27 days at 17, 20, 23, 25 and 28℃, respectively. Under short-day condition, they were 61, 47, 36, 32 and 29 days, respectively. The periods at 17, 25 and 28℃ were significantly different between two photo-regimens. Under long-day condition, the developmental zero and the total effective temperature were 9.0℃ and 320 degree-days for larval development (from egg-hatch to pupation) and 9.9℃ and 171 degree-days for pupal development (from pupation to adult emergence), respectively. Under short-day condition, those values were 6.9℃ and 384 degree-days for larval and 8.3℃ and 196 degree-days for pupal development, respectively. In December, most pupae could emerge as adults when they were warmed, but no surviving pupae were shown in and after February. We concluded that N. bazalus might not pass winter in the pupal stage at least in the north part of Kanto district, central Japan. The significance of the photoperiodic response shown in the present study was discussed.

抄録全体を表示

抄録全体を表示