Thessalia leanira wrighti

Photo Life HistoryThessalia leanira wrighti

Habitat:  Mountain Canyons. Males hilltop whereas females fly in association with their host plants.

Host Plants:  Castilleja spp.

Suitable Lab Host Plants:  Most any species of paintbrush (Castilleja).  Larvae refuse Penstemon.

Caring for Live Female Butterflies:  Feed females regularly.

Methods of Female Oviposition:  Open Screen Cages; Portable Cages.  Obtaining eggs out of live females is likely the easiest way to rear this butterfly.

How to Find Eggs:  Females lay eggs in clutches.  The number of eggs depends upon the size and concentration of host plants.  Look on the ventral side of leaves towards the lower portion of the host plant.

How to Hatch Eggs:  Consolidate eggs into one container.

How to Find Caterpillars in the Field:  Finding gregarious pre-diapause larvae can be as random as finding ova.  Post-diapause larvae can be found either resting at the base of the host or feeding on host plant flowers.  Keep in mind that once you find one post-diapause larva, start looking closer in that general area as post-diapause larvae disperse roughly within 100 feet (or so) from where the pre-diapause larvae fed.

Caterpillar setups:  For pre-diapause larvae, I recommend using the open terrariums or open bucket technique.  Overcrowding is not generally an issue.  For post-diapause larvae, see Post-Hibernation Strategies below.

Larva to Pupa:  Caterpillar silks to leaf or twig; creates and attaches cremaster; hanging as a J before pupating.

Number of Broods per Year: 1

Overwintering Stage:  Third Instar Larva.  

Overwintering Strategies: Your Own Backyard.

Post-Hibernation Strategies: When you feed post-diapause larvae after overwintering, if you're only rearing a few caterpillars, I highly recommend isolating caterpillars from sibling caterpillars using the twin cup method (or similar) in order to avoid re-diapause--an extremely common situation with checkerspots.  (See this video for more information on the twin cup method.)

Avoiding Diapause Techniques:  Not applicable.

Disease Prevention:  Change out host plant and remove frass every two to three days using the twin cup method.

Emergence:  Emergence Container

Field Notes: