Thessalia leanira alma

Photo Life HistoryThessalia leanira alma

Habitat:  Mountain Canyons; Pinyon Juniper; Desert Hills & Mountains; i.e, Utah's West Desert Mountain Ranges.  Males hilltop whereas females fly in association with their host plants.

Host Plants:  Castilleja chromosa

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.

How to Find Eggs:  Females lay eggs in clutches of app. 8 - 25; depending 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: