Am J Bot. 1998 Aug;85(8):1180.
The pollination biology of the orchid Ceratandra grandiflora was investigated in order to determine whether the partial loss of a specialized floral reward (i.e., oil) was the result of an incomplete shift from one specialized pollinator to another. In the three-species clade of section Ceratandra, there has been a progressive loss of the oil-secreting callus. lt is always present in C atrata, sometimes present in C. grandiflora, and never present in C. globosa. Thirty-nine to 67% of individuals in populations of C. grandiflora bear the callus gland, but gland presence has no signifikant effect on the proportion of flowers pollinated. Pollinator observations show that the shift in pollinators is complete and that the oil-secreting callus is a vestige of the ancestral oil-bee pollination system that no longer plays a role in pollination. C grandiflora is pollinated almost exclusively by a single species of hopliine beetle (Scarabaeidae). Experiments with artificial flower traps indicate that color alone can explain the attraction of beetles to C. grandiflora, despite the absence of a floral reward. The proportion of C. grandiflora flowers pollinated (50.2 and 61.1%; N = 524 and 324 flowers, respectively) is unusually high for a plant that relies on generalized food deception and is probably due to the use of inflorescences as mating sites (i.e., rendezvous pollination).
为了确定兰花 Ceratandra grandiflora 的传粉生物学是否是由于从一种专门的传粉者向另一种不完全转变而导致部分丧失专门的花奖励（即油），对其进行了调查。在 Ceratandra 节的三个物种分支中，油分泌的愈伤组织逐渐消失。它总是存在于 C atrata 中，有时存在于 C. grandiflora 中，而在 C. globosa 中则从未存在过。在 C. grandiflora 的种群中，有 39%至 67%的个体带有愈伤组织腺，但腺的存在对授粉花朵的比例没有显著影响。传粉者观察表明，传粉者的转变是完全的，油分泌的愈伤组织是祖先油蜂传粉系统的遗迹，它在传粉中不再发挥作用。C grandiflora 几乎完全由一种 hopliine 甲虫（Scarabaeidae）授粉。人工花陷阱实验表明，尽管缺乏花奖励，但颜色 alone 可以解释甲虫对 C. grandiflora 的吸引力。C. grandiflora 花朵的授粉比例（50.2%和 61.1%；N = 524 和 324 朵花，分别）对于依赖广义食物欺骗的植物来说异常高，这可能是由于花序被用作交配场所（即约会授粉）所致。
