Study of floral visitation on Leea asiatica

Leea asiatica (L.) Ridsdale is a common understory shrub in lowland moist deciduous forests of Western Ghats. It is visited by a variety of insects, which makes it interesting to study visitation dynamics and diversity. The objective is to get an overall view of this system and find gross trends. The work was carried out in a semi urban locality, near Aarey forest, in Mumbai, India. The field work lasted over a total of 13 days in August 2020. Data was sampled through video recordings of visitor activity on a single inflorescence every day. Visitor activity was recorded from 8am to 2pm, every 30mins. For visitation rate, the number of visits to the inflorescence and in the inflorescence, visitor identity, and time of entry and exit (for time spent on the inflorescence) were noted. For looking at visitation dynamics Apis florea was used as the candidate species because it was the most frequent visitor. Frequent visitors on Leea asiatica, were Apis florea, Braunsapis sp, members of Calliphoridae and Ceratina sp, in respective order. A total of 26 species visited L.asiatica over 13 days. The Simpsons diversity index (D) is 0.3. Mean visitation rate is 0.7±0.46 visits/inflorescence/min and 0.6 ±0.37 visits/flower/min. Overall number of visits and visitation rate dropped from 8am in the morning to 2pm in the afternoon. Handling time gradually increased till 1pm and started to drop. The trends are not always very strong as these are gross estimations and other variables were not controlled for.亚洲火筒树（Leea asiatica (L.) Ridsdale）是印度西高止山脉低地湿润落叶林中常见的林下灌木。该植物会被多种昆虫造访，因此对其访花动态与物种多样性展开研究颇具学术价值。本研究旨在全面解析该植物-昆虫互作系统，并探明相关总体趋势。研究地点设于印度孟买阿雷森林（Aarey forest）附近的半城市化区域，野外工作于2020年8月开展，总时长共计13天。数据通过每日对单个花序上的访花活动进行视频录制的方式采集。每日观测时段为早8时至下午2时，每30分钟记录一次数据。针对访花频率的统计，需记录花序及单花的造访次数、访花者身份，以及访花者的进出时间（用于计算其在花序上的停留时长）。为分析访花动态，研究选取小蜜蜂（Apis florea）作为指示物种，因其为该植物最常见的访花者。在亚洲火筒树的常见访花类群中，按出现频率从高到低依次为小蜜蜂（Apis florea）、短柄蜂属（Braunsapis）物种、丽蝇科（Calliphoridae）类群以及长木蜂属（Ceratina）物种。13天的观测期内，共计有26个物种造访亚洲火筒树。本研究测得辛普森多样性指数（Simpsons diversity index, D）为0.3。平均访花频率分别为0.7±0.46次/花序/分钟与0.6±0.37次/花朵/分钟。整体造访次数与访花频率自早8时至下午2时呈逐步下降趋势。访花者的停留时长则逐渐升高至下午1时，之后开始回落。由于本次研究仅为粗粒度估算且未控制其他无关变量，上述趋势并非始终显著。