Upland Pine, Blackwater River State Forest. Photo by Gary Knight

Tuesday, May 23, 2017

White-top Pitcherplant (Sarracenia leucophylla)

Pitcher plants have very specialized leaves that form elongated conical tubes. They are carnivorous, and capture their prey, primarily insects, by drowning them in these structures. We have two species of pitcher plant moths, genus Exyra, in Florida that are not only able to avoid capture, but eat the pitcher plants.

White-top Pitcherplant (Sarracenia leucophylla), photo by Gary Knight.

FNAI scientists recently observed pitcherplant mining moths (E. semicrocea) at two state forests in white-top pitcherplants (Sarracenia leucophylla), a globally vulnerable species which is restricted to the SE region from the Florida panhandle to southeastern Mississippi.

Pitcherplant mining moths (Exyra semicrocea), photo by Amy Jenkins.

These moths use the pitchers for food, shelter, and protection from predators. They live most of their life in the pitchers as caterpillars, slowly eating the insides of the walls, but leaving the outer surfaces intact and even repairing unintentional holes using silk. Younger caterpillars protect themselves by causing the tops of the pitchers to close up like a cap and older ones use silk to make a net-like barrier across the opening of the pitcher. The caterpillar overwinters inside of a pitcher and then goes to different pitcher to make a cocoon in, sticking itself to the side with silk after making a drain hole at the bottom of the pitcher. Adults hide in the pitchers during the day, feed from extrafloral nectaries on the pitchers towards dusk, and then fly out to mate and/or lay eggs. Much of the information about this species is known from research by Jessica D. Stephens and Debbie R. Folkerts (published here).
White-top Pitcherplant (Sarracenia leucophylla), photo by Amy Jenkins.