Shin-ya OHBA, Kaoru NUMATA and Keisuke KAWANO. Entomological Science 23, 119–127 (2020)
Variation in flash speed of Japanese firefly, Luciola cruciata (Coleoptera: Lampyridae), identifies distinct southern "quick-flash" population on Goto Islands, Japan Luciola cruciata, a bioluminescent firefly endemic to Japan, communicates with species-specific flashing patterns. Previous studies reported that flying males possess three distinct flashing frequencies: slow (4 s), intermediate (3 s) and fast (2 s). Our study focused on geographical variations in flashing patterns in the northwestern part of the Kyushu region of southern Japan (including its isolated islands) and their relationship to the mitochondrial COII region of firefly DNA. We found that "quick-flash (1 s)" fireflies occur in the Goto Islands, at the western tip of Kyushu, and that, although they possess a unique haplotype, they do not differ much genetically from "fast-flash" fireflies inhabiting mainland Kyushu. In contrast, although fireflies inhabiting the Tsushima and Iki Islands also possess a unique haplotype, their flashing patterns were the same (fast-flash) as fireflies inhabiting mainland Kyushu. We determined that flash patterns of L. cruciata in Japan should be classified according to four flashing patterns: slow, intermediate, fast and quick.
Frederick Murphy & Andrew Moiseff. J Insect Behav 33:30–37 (2020)
Ambient Illumination Influence on Photuris Firefly Larval Surface Movements is not Mediated by the Stemmata
Movements of fireflies visible on the surface of soil were measured under controlled laboratory conditions consisting of high and low ambient illumination. High illumination approximating the intensity of light prior to sunset constituted our light condition. Low illumination was consistent with ambient light levels after civil sunset, which we referred to as our dark condition. Surface movements were significantly more frequent during dark conditions compared to light conditions. Stemmata are the larval form of the insect eye and were the only identified visual organs present in Photuris larvae. We investigated whether stemmata provided larvae with the sensory information facilitating the light dependency of surface movements. We disrupted transmission of visual information from the larval eyes to the brain by severing the optic nerves. The amount of surface movement was compared between larvae with intact and severed optic nerves, under light and dark conditions. Light dependency of surface movements was preserved in larvae with cut optic nerves. The presence of the light dependency after cutting the optic nerves indicated that an alternative, extrastemmatal sensory pathway must be providing light intensity information to the animal. Light dependency was abolished upon removal of the head. Thus, these results suggested that the extraocular system providing light intensity information for regulating the frequency of surface movement was located in the head. The precise location of the suggested extraocular receptor and the nature of the associated sensory system remains unknown.
白土淳子・稲垣照美・穂積訓．日本感性工学会論文誌 16(5): 439-444 (2017)
桜と蛍の色彩に対する日本人と外国人の感性の比較研究
Abstract : We investigated the RGB and XYZ components of the natural colors (two cherry blossoms, i.e., Someiyoshino and Youkou, and the emission of Heike-firefly), and the physiological effects on Japanese and foreign people were compared. The natural colors were digitally measured as RGB colors, and then they were used as color stimuli. The psychological effects were investigated by administering a questionnaire, which was based on the Semantic differential (SD) method. From the results of the questionnaire, the degrees of expression for the natural colors were quite different between Japanese and loreigners. The kansei on the natural colors between Japanese and foreigners were also different in terms of psychophysical quantity and physical cognition. The results of factor analysis showed that the color of Youkou gave pleasantness to Japanese people, whereas the colors of Someiyoshino and firefly gave pleasantness to foreign people.
関根雅彦・後藤益滋・伊藤信行・田中浩二・金尾充浩・井上 倫道．応用生態工学 10(2): 103-116 (2007)
生息場評価手法を用いたホタル水路の建設（関根 2007）
Firefly (Luciola cruciata) is a popular and historically important insect in Yama-guchi prefecture. In the midstream of Fushino river, we could see a lot of fireflies four or five decades ago but now we cannot see not only the fireflies but also marsh snails （Semisulcospira libertina）, the only feed for the firefly. Although the local government is planning to restore the firefly habitat in Fushino River, there are a lot of difficulties to ac-complish the plan because they need to consider various firefly habitat requirements which spread from stream, ground and even to the sky together with snail habitat requirements which have not known well enough. To boost the efficiency of the restoration work, we build habitat suitability criteria （HSC） of surrounding environments （distance to paddy field, woods, slopes and city zones） and instream environments （velocity, depth and channel index） for the firefly and the snail. A physical habitat model with the HSC reveals that the midstream of Fushino River is not a good habitat for the firefly in current situation. Based on this information, an artificial stream for firefly is designed along the river and the instream habitat condition of the stream is evaluated using PHABSIM （Physical Habitat Simulation） software. Based on the calculated result, minor stream improvement works and effective flow management procedure are proposed. Post construction monitoring shows the firefly larva landing points show good accordance with the good habitat zones predicted by PHABSIM.
近藤博道・八木剛. 人と自然 17: 67-72, January 2007
大規模な出水が郡家川（兵庫県淡路市）に生息するゲンジボタルおよびカワニナ属の個体数に及ぼす影響
2004年10月に襲来した大型の台風23号の豪雨に伴う出水により，淡路市を流れる郡家川では，多くの中洲が消失するなど，河川環境が著しく改変された．本研究では，郡家川において，出水による撹乱がカワニナ属およびゲンジボタル幼虫，成虫の個体群動態に及ぼす影響について，出水前後の比較から検討した．その結果，カワニナ属の生息密度は出水後低下したものの，ゲンジボタル上陸幼虫の個体数は増加しており，発光成虫数もやや増加の傾向があり，河床地形を改変する大規模の撹乱にも関わらず，郡家川では，両種ともに著しい減少は見られなかった．