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Caterpillar laid INSIDE S. flava pitcher

Well, my Sarracenia flava is out of dormancy, and I noticed a small hole punched in its first pitcher before it opened. Today, the top has browned and died off and I wondered what got to it. I broke off the top, peered inside, and saw lots of nasty brown/black granules of crud, and something curled up in the bottom.

Well, "it" must have seen the light and gotten scared, and about 4 hours later I looked in again and a HUGE caterpillar was spinning webbing to close up the pitcher opening completely.

That's so awesome! Such a symbiotic relationship--Sarracenia provides a spawning ground, and nitrogen-rich caterpillar poop provides the first food of the year.

Sorry about the lack of pics, but could anyone give me a clue as to what kinds of caterpillars like to nest in Sarracenia pitchers? I live near Athens, GA--probably within the native range of any butterfly species that have evolved with Sarracenia in the southeast. I wondered what bug would possibly know to target Sarracenia, as it's quite foreign to the Piedmont. It looks green with black stripes.

Very, very smart bug. I'll try and give some updates as to what the thing does if anyone's interested.
 
Don't forget wasps and moths do things like that to.
 
if i remember the name correctly its like a Xyra(please feel free to correct anyone!) moth. thats BAD! they can totally destroy pitchers. new and old. the caterpillars can survive some insane cold too. they are mainly found in flava pitchers....but can just as easily survive in any others. i had an outbreak last year with a new shippment of sarrs and cut the dead pitchers to the very nub. the little pillars made great food for my Neps :) they are tough to get rid of and can make your sarrs look horrible. good luck.

heres a pic of the worm(my picture) :
IMG_1845.jpg


Alex
 
Probably the larvae of the dreaded Exyra moth, most likely Exyra ridingsii, you're in their natural range and they infest S. flava:

http://bugguide.net/node/view/40429/bgpage


Exyra ridingsii
“Ridingsii passes the winter in the larval stage in a carefully constructed hibernaculum. These hibernating larvae occupy sealed chambers low down in the dry stems of the leaves of flava, much more rarely in minor. This chamber is constructed in the dry corky frass which fills the lower portion of the leaf in which the larva has been feeding, is ceiled with an arched button of closely compressed particles line beneath with silk, the leaf forming the walls and another accumulation of packed frass the floor. The space occupied by the larva is usually about an inch in length, but is sometimes much longer. This portion of the leaf, dry and dead in flava, green in minor, shows no trace of feeding, though the larvae become active long before leaving their winter quarters.

About April 15th, they leave these hibernacula, rupturing the ceiled roofs and creeping up through the loose frass above. After an interval of several days spent apparently without feeding, during which they may be found in the litter of dead and broken leaves of the preceding year, they creep up the tender hew leaves, eat a round hole in the side, and immediately creep in. This occupies only about two minutes, and is the method of entrance without regard to whether the leaf chosen is a mature one, open at the top, or an unopened one. In the former case the larva ceils the open top with a transparent but strong silken web, and sometimes, but rather exceptionally, cuts a groove around the leaf internally, which eventually aids in bringing about the collapse of the upper portion of the leaf. This year, however, fully ninety five percent of the larvae chose immature, unopened leaves, the earlier leaves having been killed by the late frost.
Exyra semicrocea
Exyra fax

Control methods:

Systemic insecticides - since the larvae and the moth spend most of their lives inside the pitcher tube contact insecticides like Pyrethrin are less effective.
Bacillus thuringiensis - spray leaves and pour a little into the pitchers. Effective against only the larvae.
Manual removal - difficult again since the larvae live inside the pitchers. Some people gently squeeze the pitchers listening for a satisfying pop of the larvae being crushed. Prolonged immersion may not be effective since the silk canopy would create a sizable air chamber.
 
I don't know if it's probably a xyra moth; there are plenty of other bugs that are smart enough to do that. But definitely worth looking into... I understand syra moths are quite a problem for collections.
~Joe
 
Yeah, those thing destroy the pitchers!:cuss:
 
Yeah, that's what I've got. Thanks a great deal for the ID, everyone, especially without pics!!

Several questions:
1) Does it feed in any way on the rhizome?
2) Does it destroy the bottom (i.e. nutrient absorbing zone) of the pitchers?
3) Does it return to reinfest the plant's pitchers the remainder of the growing season?
4) How in the world does it get out of the pitcher? It's sealed the top of the pitcher shut completely with silk and pulled it together airtight.

I can suffer this one loss without killing the thing, as it appears to be a fairly rare type of moth. It's a great natural check on Sarracenia populations in the wild, I imagine, and possibly might benefit them with caterpillar frass (although it'd mean the plant is indirectly eating itself...). I'll at least let it complete its lifecycle so I can have practical visual experience as to the extent of damage it does to the pitcher itself. If it gets to be a problem, I'm going to have to side with the plants, unfortunately, and get rid of it.
 
More information of the life cycle of the Exyra fax is in this article. Exyra fax is more specific to Sarracenia purpurea but the life cycle is similar.

From the earlier cited entry on Exyra ridingsii (emphasis mine):

In these closed leaves the larvae invariably commence feeding at the top of the leaf, soon causing the hood and closed lips of the leaf to collapse, thus effectually closing the tube and obviating the necessity for a ceiling web, which however, is sometimes spun some distance down the tube. The notch-cutting habit was not practiced in any of these immature leaves. As the larvae spin a carpet of silk wherever they go, this also aids in keeping the tube effectually sealed and in preventing the opening of the growing leaf. These hibernating larvae vary greatly in size, and molt at least once before the last larval stage is reached. After taking possession of a leaf, the lower portion of the tube fills up with corky frass particles, in which the cocoon is spun, the larva having previously cut two holes through the leaf wall, a large one above for the emergence of the moth, and by burrowing down in the frass-filled tube, a small one some distance below the location chosen for the cocoon, this second hole being apparently for drainage; just above this drainage hole and between it and the cocoon, the tube is sealed with a lightly spun web, usually not two closely spun to retain the water. The small hole where the larva entered the leaf, unless obliterated by feeding of plugged with the accumulated frass, is usually closed with a web. The larva sometimes changes from the old leaf to a new one, and when this occurs just before pupation, unlike semicrocea, it eats enough of the new leaf to furnish frass and nibbled particles to render the cocoon opaque; usually, however, the cocoon is composed of the corky frass particles loosely held together with silk, and is built against one side of the tube, the leaf-wall on that side forming one wall of the cocoon.

…In ridingsii the pupal stage lasts ten to twelve days, emergence taking place in the daytime, usually between twelve and four o'clock. The pupa sometimes forces itself through itself through the top of the escape of the moth. Pupation of the spring brood takes place from May 8th to May 20th, and the emergence of moths is complete by June 1st . The moths are extremely variable, some examples being suffused with black to the obliteration of all markings on the wings.


Papaipema appasionata is the so-called pitcher plant root borer will bore into the rhizome as will some of the armyworms. I haven't determined the species of armyworm yet, possibly Leucania unipuncta.
 
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