Red-lined Scrub-Hairstreak (Strymon bebrycia) life history
Red-lined Scrub-Hairstreak (Strymon bebrycia) Life History


neonate, 12-4-19

first instar, 12-4-19

second instar, 12-6-19

Entry hole covered with silk, 12-14-19

Third instar, 12-14-19

Fourth instar, 12-18-19

Caterpillar entering balloon, 12-18-19

Pupa, 12-18-19

Fresh adult Red-lined Scrub-Hairstreak, ventral, 1-12-20

Fresh adult Red-lined Scrub-Hairstreak, dorsal, 1-12-20

I found a few hairstreak eggs on Balloon vine (Cardiospermum halicababum) in an area where Red-lined Scrub-Hairstreaks had been reported flying. The day I visited the site, at least one Silver-banded Hairstreak (Chlorostrymon simaethis) was flying around, so I really had no idea what, if anything, would come out of the eggs. As it turned out, 3 caterpillars emerged, 2 of which were Red-lined Scrub-Hairstreaks.

Silver-banded Hairstreak larvae, in my experience, spend their "childhood" inside the balloons, or seed pods, of the host plant. They feed on the green seeds and only emerge when the need for food dictates they change balloons. Middle instar Red-lined Scrub-Hairstreaks also took advantage of the convenient shelter. One of the second-instars carefully silked the entrance hole it made when it entered a fresh balloon (see 12-14-19 picture). were far less attached to the shelter of the balloons. However, hatchlings and late instars were apparently not as particular about shelter. The first instars spent some time feeding on flowers, even though balloons were provided. Late instars ate the balloons themselves as well as the seeds, again while fresh balloons were available. I initially thought that feeding on a wider range of plant tissues should give the Red-lined Scrub-Hairstreaks a competitive advantage over their green cousins. Upon reflection, given that Silver-banded Hairstreaks are far more common in this area, perhaps feeding outside the balloons makes the bebrycia larvae more vulnerable to predators and/or parasites.

I forget now what made me try the experiment, but I found that UV light (from a black flashlight) encouraged the fresh adults to spread their wings so that I could get decent pictures of the dorsal surface.

Both of the study caterpillars emerged on 12-4-19. The first pupated on  December 26 after 4 days in the prepupal state; the adult emerged on January 12. The second pupated a couple of days after the first, and emerged on January 16. Thus, the journey from egg to adult took about 5 weeks in our mild winter temperatures.

Red-lined Scrub-Hairstreak Page