Department of Environment and Agriculture, Curtin University, Bentley, WA, Australia.
Department of Biology, University of Naples Federico II, Complesso Universitario MSA, Naples, Italy.
Ann Bot. 2018 Nov 30;122(6):1061-1073. doi: 10.1093/aob/mcy166.
While there is increasing recognition of Batesian floral mimicry in plants, there are few confirmed cases where mimicry involves more than one model species. Here, we test for pollination by mimicry in Diuris (Orchidaceae), a genus hypothesized to attract pollinators via mimicry of a range of co-occurring pea plants (Faboideae).
Observations of pollinator behaviour were made for Diuris brumalis using arrays of orchid flowers. An analysis of floral traits in the co-flowering community and spectral reflectance measurements were undertaken to test if Di. brumalis and the pea plants showed strong similarity and were likely to be perceived as the same by bees. Pollen removal and fruit-set were recorded at 18 sites over two years to test if fitness of Di. brumalis increased with the abundance of the model species.
Diuris brumalis shares the pollinator species Trichococolletes capillosus and T. leucogenys (Hymenoptera: Colletidae) with co-flowering Faboideae from the genus Daviesia. On Di. brumalis, Trichocolletes exhibited the same stereotyped food-foraging and mate-patrolling behaviour that they exhibit on Daviesia. Diuris and pea plants showed strong morphological similarity compared to the co-flowering plant community, while the spectral reflectance of Diuris was similar to that of Daviesia spp. Fruit-set and pollen removal of Di. brumalis was highest at sites with a greater number of Daviesia flowers.
Diuris brumalis is pollinated by mimicry of co-occurring congeneric Faboideae species. Evidence for mimicry of multiple models, all of which share pollinator species, suggests that this may represent a guild mimicry system. Interestingly, Di. brumalis belongs to a complex of species with similar floral traits, suggesting that this represents a useful system for investigating speciation in lineages that employ mimicry of food plants.
虽然植物中贝氏拟态的现象越来越受到关注，但涉及到一种以上模型物种的拟态案例却很少。在这里，我们检验了兰花科的迪里厄斯属（Diuris）植物是否存在通过模仿一系列共存的豌豆植物（豆科）来吸引传粉者的拟态现象。
使用兰花花束对迪里厄斯·布鲁马利斯（Diuris brumalis）的传粉者行为进行观察。对共花期群落中的花朵特征和光谱反射率测量进行分析，以检验迪里厄斯·布鲁马利斯和豌豆植物是否表现出很强的相似性，并且很可能被蜜蜂视为同一物种。在两年内的 18 个地点记录花粉去除和果实设置，以检验迪里厄斯·布鲁马利斯的适合度是否随模型物种的丰度增加而增加。
迪里厄斯·布鲁马利斯与共花期的 Daviesia 属豆科植物共享传粉者 Trichococolletes capillosus 和 T. leucogenys（膜翅目：Colletidae）。在迪里厄斯·布鲁马利斯上， Trichocolletes 表现出与 Daviesia 相同的刻板觅食和配偶巡逻行为。与共花期植物群落相比，迪里厄斯和豌豆植物表现出很强的形态相似性，而迪里厄斯的光谱反射率与 Daviesia spp. 相似。在有更多 Daviesia 花的地点，迪里厄斯·布鲁马利斯的果实设置和花粉去除率最高。
迪里厄斯·布鲁马利斯是通过与共存的同属 Faboideae 物种的拟态进行授粉的。对多个模型的拟态证据，这些模型都共享传粉者物种，表明这可能代表了一个群体拟态系统。有趣的是，迪里厄斯·布鲁马利斯属于具有相似花型特征的物种复合体，这表明这是一个用于研究利用食物植物拟态的谱系物种形成的有用系统。
