bfly (sciname) life history
Gold-spotted Aguna (Aguna asander) Life History


A fresh egg, 8-2-20

A developing egg, 8-2-20
            

Neonate starting shelter, 8-3-20

Different neonate, leaves sewn together
            

First instar
            

Second instar
     

Third instar
     

Fourth instar
     

Fifth instar
     

Pupa, 8-20-20
     

Fresh adult Gold-spotted Aguna, dorsal view
     

Fresh adult Gold-spotted Aguna, ventral view, after release 8-31-20
 

Hurricane Hanna passed directly over Starr County on July 26, 2020. While the storm caused significant flooding closer to the coast, we were fortunate to receive good rains and minor wind damage. The following Sunday, August 2, I observed a Gold-spotted Aguna ovipositing on one of my potted Mexican Orchid Trees (Bauhinia mexicana). I also had an Orchid Tree planted in the yard; upon inspection, this tree proved to have numerous eggs, some of which were already showing signs of development. Throughout the following week I observed more adults nectaring and/or ovipositing in the yard; Thursday, August 6, was the last day I observed oviposition. Egg-laying did not seem to be influenced by time of day: I saw eggs being placed from just after noon until as late as 7:30 in the evening. (On the final day, I also observed a Tailed Aguna [Aguna metophis] place eggs on the yard's Orchid Tree; these showed development but never hatched.) I had seen more Agunas in one week than in the 10 previous years, and many others were reported throughout the Rio Grande Valley. Clearly, the rains from Hanna brought about a strong flight!

The eggs were primarily placed near the tips of tender, half-grown leaves that were still folded together. However, the emerging caterpillars tended to move toward nearby, full-sized leaves to feed and nest. The preference for nesting seemed to be to move to the midrib of the leaf and draw the leaf halves together to form a shelter. A few first instars did cut and fold a piece of leaf along the edge, as do many other skipper species, but none stayed in these shelters long. When feeding, the caterpillars showed a strong preference for full-sized but tender leaves. These were all consumed before some of the later-hatching caterpillars pupated; once they were forced to feed on older, thicker leaves, growth seemed noticeably slower. Unfortunately, the last two died, apparently because the available leaves were unsuitable.

 


Face of Gold-spotted Aguna

Some caterpillars fed on the leaf they used for shelter; others would move out to forage other leaves. The shelters were changed frequently, even when apparently still in quite suitable condition. The caterpillars actively fed and grew for about two weeks, then took a couple of days to pupate - usually in a leaf shelter. The first adult emerged August 31, 29 days after I first found eggs.

For the study, I had 2 potted plants with 8-10 eggs which I had brought inside and placed in pop-up cages to observe. I also sleeved a number of eggs on the planted bush. In this way I was able to rear and release at least 10 adults. During the time period I was releasing the Agunas I had reared, I saw a couple of additional adults flying, which suggests the captive rearing did not affect their development. Interestingly, the week of September 20 there was another flight. The timing suggests these adults were a distinct group, perhaps brought out by nearby rains that missed us. However, no further eggs were found.

Gold-spotted Aguna Page