The bottom of the hollow pitcher, zone 3, is lined with glands which secrete digestive enzymes and zone 4 with absorptive glands. These enzymes are effective in the chemical breakdown of prey, except for the more resistant portions of the insect's body, such as chitin. Numerous organisms exist and thrive in the liquid that accumulates in the base of the pitchers. Among these denizens are yeast cells and bacteria which assist in the digestion of the prey, although the full extent of their role has not been ascertained. In any case, digestion does occur and protein is broken down into amino acids, which are absorbed by the plant along with minerals. The efficiency of Sarracenia pitchers is attested to by the numerous insects and their remains that accumulate in the base of the pitchers. Some of the more common victims are ants, beetles, crickets, wasps, spiders, flies of various kinds, and occasionally small toads.
While Sarracenia is famous for its carnivory, not all insects succumb to the lures which lead most prey to their death. In fact, many insects feed on the plants' pitchers and rhizome, while others live in the fluid bath and still others make use of the pitchers to capture insects in their own way and for their own use.
One of the most intriguing members of Sarracenia society is a group of moths of the genus Exyra. Depending on the species, they lay one or more eggs in each pitcher. If more than one egg has been laid in the pitcher, upon hatching, one of the larvae will kill the others or drive them off so that only one larva of the species remains per pitcher. Thus, a single plant with five pitchers supports a maximum of five larvae. Another species in this group lays its eggs in the area surrounding the mouth of the pitcher. When the eggs of the moths hatch, the emerging larvae eat the superficial tissue of the pitcher, causing eaten areas to become translucent.
Eggs from another species of Exyra hatch into larvae which feed on the pitcher walls and produce a tent of silk. Members of this group often spin a net or webbing across the opening of the pitcher, forming a home with protection against rain and other insects. An even more ingenious species of Exyra forms a home for its eggs in a unique way. Shortly before the larva pupates, it eats the superficial material from a narrow zone encompassing the whole circumference of the inside of the pitcher, at about one third the distance from the bottom of the pitcher. This results in a groove being produced, in effect girdling the pitcher. The pitcher above this groove dies, dries out and becomes somewhat leathery. Since the grooved area of the pitcher is considerably weakened because part of the wall has been removed, the weight of the pitcher above the groove, aided by wind, will cause the pitcher to fold over, effectively barring rain and unwanted visitors from the pitcher chamber.
Larvae of another species of this group of moths plan ahead for their escape after pupating into a moth by eating an opening in the pitcher wall through which they can escape. Another hole is eaten below the escape hatch so that if rain enters the chamber, it will not flood because the water can drain out through the lower hole. This group of moths, whose larvae not only use the pitchers as a dwelling place but also derive nourishment from the tissues of the walls, does not limit its appetite to the pitcher but will also devour the flower and even the rhizome.
Creatures such as spiders inhabit the mouth of the pitcher and some build webs and catch prey in the mouth area. Often the web will completely cover the opening. We have observed a small toad waiting just outside the mouth of the Sarracenia purpurea pitcher for some prey to come along.
The caterpillar (larvae) of Papaipema appassionata lives on rhizome tissue that it bores out of Sarracenia rhizomes, thereby forming hollow tubes. This larvae leaves its tell-tale evidence at the surface, a pile of debris which is colored light brown, granular, and resembles earthworm castings.
Alabama Canebrake Pitcher Plant. Species designation is being contested at this time. Some taxonomists feel it is a subspecies of S. rubra.
The Pale Pitcher, formerly named S. sledgei. Huntsman's Horn, and Yellow Pitcher. There are at least five color variants in this species.
White Trumpet, formerly named S. drummondii.
The Hooded Pitcher Plant. The Green Pitcher Plant. Parrot Pitcher
Purple Pitcher, Pitcher Plant, and Northern Pitcher Plant. Formerly named S. purpurea ssp. gibbosa.
Southern Pitcher Plant Sweet Trumpet
These two are the same plant. Some botanists consider this plant a species, whereas others consider it a subspecies.
**Species which produce ensiform or winter leaves known also as phyllodia.
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