Four-spotted Sailor (Dynamine postverta) Life History


Egg

Neonate
     

First instar
            

Second instar
     

Third instar
     

Fourth instar
     

Fifth instar
     

Fifth instar with brown markings (just molted)
     

Chrysalis
     

Fresh adult male Four-spotted Sailor, ventrum, 7-12-15
     

Fresh adult male Four-spotted Sailor spreading new wings, dorsum, 7-12-15
 

In  June, 2015, I confined a female Four-spotted Sailor in a netted container with Tragia glanduligera (Noseburn) and Dalechampia scandens. When no eggs were produced after two days, I began to occasionally mist the container. The following day oviposition began. It is reasonable to suppose, but not certain, that the misting helped. Virtually all of the eggs were placed on Dalechampia, but I did find 3 on Noseburn.

Summer of 2015 was not a good year for caterpillars in this area: a pathogen of some type (perhaps viral) seemed to be affecting most species I observed, whether they were in natural conditions or reared in captivity. I took the utmost care with the Sailor larvae, but even so most eventually died. Particularly disappointing was the loss of the three that hatched on Noseburn. They began feeding, but they all died in the first instar (apparently of the disease), so I was not able to determine if the plant was a viable host.

On Dalechampia, the caterpillars fed both on leaves and flower parts. Those that fed on flower tissue grew faster and appeared to have a higher survival rate than those that fed on leaves.

Eight caterpillars made it to the final instar. One died while pupating. After five days, the first two pupae turned color, but the adults did not emerge. Therefore, I began misting the chrysalises heavily; I also added a potted plant to the container to keep the humidity high. Eventually the 5 remaining adults did emerge: 4 females and one male.

 


Face of Four-spotted Sailor

The female was confined on June 19; eggs began appearing on June 22, and hatching began on June 25. Five instars were observed. Pupation began July 5, and adults appeared from July 12-14. The entire cycle took approximately 3 and one-half weeks.

Four-spotted Sailor Page