Journal list menu

Volume 101, Issue 3 e01726
Photo Gallery
Open Access

Sweet Flag Flowers Act as Cradles for Tiny Beetle Pollinators

First published: 07 July 2020

Study Description

Sweet flag, Acorus calamus, is one of the basal-most monocots and is commonly found in wetlands of the Northern Hemisphere. Although sweet flag has long been considered insect-pollinated, the pollinators of this plant have never been reported. We found that two species of tiny beetle, Platamartus jakowlewi and Sibirhelus corpulentus (Kateretidae), carried pollen grains of sweet flag in Japan. These beetles oviposit on the inflorescences, and the hatched larvae feed on pollen and other plant tissues of inflorescences. Our results suggest that the basal-most monocot Acalamus is pollinated by specialized beetles that use the inflorescences as a breeding site.

Details are in the caption following the image
Sweet flag Acorus calamus and its habitat. An inflorescence in male phase (left) and a patch in an abandoned paddy field (right). Photo credit: Daichi Funamoto.
Details are in the caption following the image
Kateretid beetles on inflorescences of sweet flag Acorus calamus. Sibirhelus corpulentus (left) and Platamartus jakowlewi (right). Photo credit: Daichi Funamoto.
Details are in the caption following the image
Fruits of sweet flag Acorus calamus and the larvae of beetle pollinators. A mature inflorescence damaged by Sibirhelus corpulentus larvae (left), larvae of Scorpulentus constructing pupal chambers in a mature inflorescence (top right), and a larva of Platamartus jakowlewi on an inflorescence in male phase (bottom right). Photo credit: Daichi Funamoto.

These photographs illustrate the article “Entomophily in Acorus calamus: implications for brood-site pollination mutualism in basal-most monocots” by Daichi Funamoto, Tomoyuki Suzuki, and Shinji Sugiura published in Ecology.