An occasional butterfly species visitor to NJ was spotted recently near Merrill Creek Reservoir. According to the NJ Butterfly Club (A Chapter of the North American Butterfly Association), this species, the Little Yellow (Eurema lisa) is very small — 1.3” (much smaller than Clouded Sulphur Butterfly). The male is bright yellow with many small, dark spots plus a larger, palish rusty-pinkish spot at hind wing apex. Two tiny black spots at base of forewing clinch the ID. The female is lighter yellow with variable markings usually bolder than the male’s, particularly the Hind Wing apex spot. Rarely seen basking with open wings.
It is a nonresident of NJ. Primarily a southern species that occurs as a regular stray in NJ. Although reported from throughout the state most of the reports are from the southern NJ counties. However, it establishes small, temporary colonies where the ephemeral host plants are common.
The host plants of the Little Yellow are Partridge Pea (Chamaecrista fasciculata) and Wild Sensitive Plant (C. nictitans). While MCR does not have Wild Sensitive Plant, MCR does have lots of Partridge Pea!
Starting 3 years ago, MCR started incorporating the native Partridge Pea seed into meadow restorations, pollinator gardens and even in soil stabilization projects. Partridge Pea provides vital support to local ecosystems by feeding pollinators, hosting butterfly larvae, enriching the soil as it is a nitrogen fixer, and supplying crucial winter food (its seeds) for birds. Also, the plant’s small glands at the base of the leaves secrete nectar that not only attract bees and butterflies, but it also attracts ants, wasps, and lady beetles. In exchange for the nectar, these predatory insects protect the plant by eating harmful insect pests. In fact, one study done at the University of Maryland, titled “Partridge Pea: Your Local Community Buffet for Natural Enemies in Organic Corn,” suggests it may even act as a trap crop, luring pests like stink bugs and the European corn borer away from corn crops.
Partridge pea is also a larval host plant for the Io Moth, Gray Hairstreak, Sleeping Orange Butterfly, Cloudless Sulphur Butterfly, and Common Tan Wav Moth.
If you see a Little Yellow at MCR please let us know where you encountered it on the property, the date and forward any photos of it to MCR at jparke@merrillcreek.com 
