Dusky-blue Groundstreak (Calycopis isobeon) Life History

       Eggs laid 3-04-09               Just after eclosing, 3-9-09

3-10-09 by end of a paperclip                         3-12-09; still "hairy"          

3-20-09; they are the same age but one is twice the size of the other


3-30-09; just above the caterpillar are shed skins from 2 previous molts


4-4-09, almost ready to pupate

4-6-09, pupa fully formed, 28 days after caterpillar eclosed.

4-17-09, the recently emerged Dusky-blue Groundstreak.

The eggs for this study were obtained from a captive female.  All were laid in crevices in bark chips, as can be seen in the first photo. I have collected eggs this way several times now; occasionally the females have used dried leaves, but the majority of the eggs have always been laid on bark chips.

Dusky-blue Groundstreaks are reported to eat decaying matter. I had observed a female laying eggs on detritus under our lime tree. Therefore, I provided both fresh and dried lime leaves as a potential food source. Although the caterpillars did not eat the leaves, they liked to crawl under them while resting. (I was able to keep the same leaves with the caterpillars through most of the study; whether they felt better having a familiar roost was never clear, but at least I didn't have to disturb them as much when cleaning...) 

A post by Nick Grishin on the Texas Butterfly Listserv suggested that bread mold was a suitable food for the caterpillars. So I offered this as well as the leaves. In order to keep track of tiny caterpillars, I used a minimalist approach: small containers  and small amounts of food. The bread quickly became stale and hard under these conditions, so I decided to add some banana peel to maintain the humidity. This proved a serendipitous choice: the tiny caterpillars decided they liked the banana peel better than the bread - either that or it lacked sufficient mold. As the caterpillars got older, they did eat bread mold as well as banana.

(With a second batch of caterpillars, a single mesquite bloom somehow fell into the container a day or so after they eclosed, and they devoured it. So I added mesquite blossoms as well as bread and banana; the young caterpillars seemed to eat all three.)

In this study, the female laid 9 eggs on the second day of captivity. After that I released her. All 9 eggs eclosed, and 6 caterpillars survived to pupate. The other three died within the first week after eclosing. The caterpillars grew at different rates, as is evident in the picture taken on 3-20. The first pupated on 4-6, four weeks after eclosing. The last pupated 5 days later. The first adult emerged on 4-17-09.