Brood pollination mutualism between cryptic-flower Aspidistra and pollen-parasite midges

Area of Science:

• Ecology
• Evolutionary Biology
• Botany

Background:

• Brood pollination mutualisms often involve insects parasitizing flowers.
• The evolution of pollen parasitism in nursery pollination systems is poorly understood.
• Aspidistra flowers are typically cryptic and found under forest litter.

Purpose of the Study:

• To investigate pollination systems in seven Aspidistra species.
• To determine the role of pollinators and their life cycles in relation to floral resources.
• To explore the potential for pollen parasitism in these interactions.

Main Methods:

• A 9-year field study examining floral phenology, anthesis, pollinator feeding habits, and life cycles.
• Observation of interactions between Aspidistra species and their pollinators.
• Analysis of larval development and diet within flowers.

Main Results:

• At least six Aspidistra species are pollinated by fungus gnats or gall midges.
• Larvae of these pollinators were identified as pollen parasites.
• Aspidistra saxicola exclusively utilizes a midge pollinator, with larvae developing on pollen within 3-4 days.
• Pollinator life cycles are synchronized with floral pollen availability for 4-7 days.

Conclusions:

• A new form of fly-pollinated pollen-parasite mutualism in angiosperms is described.
• Unlike seed-predating larvae in other systems, these pollinators are entirely pollen-dependent.
• This research expands our understanding of obligate brood pollination mutualisms.