Starr County Butterflies
Leaf shelter when found (note empty egg on right leaf, 11-14-10
Caterpillar on day found, 11-14-10
11-16-10
Eyespots appear, 11-22-10
Eyespots, feet now orange, 11-28-10
Face coloration has changed, 12-4-10
Face has more red, 12-6-10
Caterpillar will soon cease to be blue-green, 12-15-10
This and succeeding instars are quite colorful, 12-29-10
A month later: slightly darker, a little larger! Side view, 1-29-11
2-6-11
Mature caterpillar, 2-21-11
Chrysalis, 3-12-11
Fresh adult White-striped Longtail, 3-29-11
Fresh adult female White-striped Longtail after release, ventral, 3-29-11
I was excited to find an early-instar skipper caterpillar on Least Snout Bean, Rhynchosia minima, in November, 2010. I was not so excited when, three months later, I was still having to take care of this same caterpillar! This caterpillar, a White-striped Longtail, proved to be the slowest-maturing I have yet to raise. Granted, it developed during cooler winter weather, and a few times it seemed to cease feeding for a couple of days, but frass production never stopped and it never entered diapause.
As is often the case with skipper larvae, the first- or second-instar caterpillar was green with a black head. After a week, the body showed a yellow lateral stripe, and markings appeared on the face. A month after being collected, the caterpillar was quite attractive with a blue-green body and orange feet. It became even more beautiful in the succeeding instar, when the body became a light purple color. It was at this time that the face took on its characteristic markings.
close-up of face, 1-12-11
By now it was the end of December. For the next two months, the caterpillar changed very little. Finally, in early March, it became dark and was clearly prepupal. Again, it was in no hurry: the caterpillar was in the pupal position three days before the chrysalis formed. The chrysalis was black with a heavy sprinkling of what appeared to be white powder. Because of the dark color, I could not see indications that the adult was ready to emerge. I had left the lid on the container rather loose, and one day was surprised to arrive home and find the skipper not only emerged; it managed to push up the lid and crawl out of the container and fly to a window. As it was already very active, it was unwilling to pose for good pictures when released....
After the early instars, the caterpillar stopped making leaf shelters on the plant. A couple of times, it made a shelter by sewing a leaf to the top of its container. Eventually, it made a nest of leaves in the bottom of the container. I watched the nest carefully for mold, and occasionally removed a leaf, but the caterpillar seemed unaffected and insisted on using the same shelter until it was ready to pupate.
Over four and one half months after I found the caterpillar, the adult White-striped Longtail finally emerged. Considering that the egg was probably deposited another week to two weeks previously, the journey from egg to adult for this skipper took about five months. That is quite a long time, considering it did not enter diapause or overwinter in the pupa!