J Syst Evol

• Research Articles •    

Intersexual mimicry and imperfect deceit of a threatened aquatic herb Ottelia acuminata

Jing Yang1,2+, Yang Niu2+, Wei-Bang Sun1,2, Xiang-Hai Cai3*, and Gao Chen1,2*   

  1. 1Yunnan Key Laboratory for Integrative Conservation of Plant Species with Extremely Small Populations, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650201, China

    2 CAS Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650201, China

    3State Key Laboratory of Phytochemistry and Plant Resources in West China, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650204, China


  • Received:2020-05-07 Accepted:2020-06-24 Online:2020-07-08

Abstract:

Mimicry of non‐rewarding flowers to rewarding flowers has been accepted as a strategy to improve pollination success in angiosperms. It has been proposed that this mechanism depends on whether potential pollinators can discriminate between the flowers. In this study, the intersexual mimicry and deceit pollination were studied in a threatened dioecious aquatic herb, Ottelia acuminata. Its female flowers resemble male flowers in morphology and odor compounds, to avoid discrimination by pollinators and outcompete male flowers in attracting the pollinators using stronger scents and bigger flowers. However, an obvious visit bias of its pollinator (Apis cerana) to male flowers was detected, suggesting that bees can distinguish the rewarding males from non‐rewarding females. Although the deceit was not successful, pollination was not seriously undermined because pollen limitation was found to be low in the sampled natural population. We speculate that, due to “accidental” visits on female flowers and “mistake” pollinations, pollen limitation could be mitigated by a high frequency of pollen donors, and is correlated with the size and sex ratio of a population.

Key words: deceit pollination, dioecy, intersexual mimicry, Ottelia acuminata, pollinator preference, sex ratio