Fertilization of Webera stellulata
This short note by H. N. Ridley describes the fertilization mechanism of Webera stellulata, a Myrtaceae species with inconspicuous green flowers, and briefly surveys pollination ecology in related genera.
Summary
Ridley documents that Webera stellulata possesses a mechanical self-fertilization device: the petals are twisted in bud and held tightly by adjacent petals, so that a light pressure (from an insect or otherwise) causes them to spring open suddenly, jerking loose pollen onto the stigma of an adjacent flower or onto the visiting insect (p. 127). Given the inconspicuousness of the green flowers compared to the sweet-scented white blossoms of other Webera species, Ridley concludes that the plant most probably fertilizes one flower with the pollen of another rather than relying on insect pollination (p. 127).
The note also includes brief observations on pollination in other Myrtaceae—Eugenia species visited by bees, syrphids, and butterflies; Eugenia ridleyi visited by muscids; and Rhodamnia trivervia visited by Apis, Trigona, and syrphids (p. 126)—as well as a mention of an apparently undescribed Careya species in the Botanic Gardens jungle with similar fertilization ecology. Distribution records (Singapore, Johore, Selangor, Negri Sembilan) and Malay names (Kahwa hutan, Kuruseh putih, Pokoh Subiroh) are provided, with a flowering period of December to June (p. 127).