The mycoheterotrophic orchid Cyrtosia septentrionalis, known for its vibrant red, sausage-shaped fruits, has found an unexpected ally in seed dispersal. While birds were thought to be its primary dispersers, recent research by Kenji Suetsugu reveals a surprising player: the carnivorous masked palm civet. This finding challenges previous assumptions about orchid seed dispersal and highlights the potential for diverse dispersal strategies in plants.
The study revealed masked palm civets as primary consumers of Cyrtosia septentrionalis fruits. Unlike birds, civets crushed the fruits, consuming larger portions. Seeds remained viable after passing through the civet’s digestive system, with viability rates comparable to seeds from intact fruits. This suggests civets play a significant role in seed dispersal, potentially over longer distances due to their larger home ranges. The findings indicate C. septentrionalis likely employs a mixed bird-mammal dispersal strategy.
Suetsugu conducted the study from December 2014 to February 2015 in a forest in Shiga Prefecture, Japan. He used motion-sensing cameras placed near Cyrtosia septentrionalis plants to identify fruit consumers. Civet droppings were collected and examined for orchid seeds. Seed viability was tested using 2,3,5-triphenyl tetrazolium chloride (TTC) staining. The viability of seeds from civet droppings was compared to seeds taken directly from intact fruits using statistical analysis.
This study challenges previous assumptions about orchid seed dispersal. While birds were thought to be the main dispersers for Cyrtosia septentrionalis, civets may play an equally important role. Civets’ larger home ranges suggest potential for longer-distance seed dispersal compared to birds. This research adds to growing evidence of diverse seed dispersal strategies in orchids, highlighting the complex interactions between plants and animals in forest ecosystems.
Suetsugu, K. (2024). Further evidence for endozoochory in a mycoheterotrophic orchid Cyrtosia septentrionalis: seed dispersal by the masked palm civet Paguma larvata. Plant Biology. https://doi.org/10.1111/plb.13718
ResearchGate: https://botany.fyi/z9w80c
