Eurema mexicana
(Boisduval, 1836)
Mexican yellow, wolf-face sulphur
Eurema mexicana is a -sized in the , primarily distributed in Mexico with occasional northward strays into the southwestern and central United States. The is distinguished by a distinctive black border forming a 'wolf-' or 'dog-face' pattern, and exhibits seasonal color variation on the underside. Males hilltops and open areas seeking females throughout the day.
Pronunciation
How to pronounce Eurema mexicana: //juːˈriːmə ˌmɛksɪˈkɑːnə//
These audio files are automatically generated. While they are not always 100% accurate, they are a good starting point.
Identification
Distinguished from Eurema boisduvaliana (Boisduval's ) by larger size, duller yellow color, stronger 'dog ' pattern in males, more extensive black on female upperside, and more sharply pointed . Distinguished from Eurema salome (Salome yellow) by duller yellow color, more extensive black on upperside, and lack of round reddish spot near trailing edge on hindwing underside.
Images
Appearance
Wingspan 32–57 mm. Upperside pale with black submarginal border outlining a 'wolf-' or 'dog-face' pattern. has small outer margin black border. Male has bright yellow on leading edge of hindwing. Hindwing sharply pointed. Underside pale yellow in summer individuals; pale yellow with reddish markings or entirely reddish-pink in winter individuals.
Habitat
Open including woodland edges, open woodlands, and desert grasslands.
Distribution
Primarily Mexico; occasionally central and southwestern United States (Arizona, Texas, New Mexico); rare stray to Canada (Manitoba, Saskatchewan).
Seasonality
Year-round in Arizona and Texas; April to November in New Mexico. Northward strays occur in late summer.
Diet
: nectar from flowers. : New Mexican (Robinia neomexicana), fern acacia (Acacia angustissima), prairie acacia (Acacia angustissima var. hirta), Cassia , and Diphysa robinoides.
Host Associations
- Robinia neomexicana - larval New Mexican
- Acacia angustissima - larval Fern acacia
- Acacia angustissima var. hirta - larval Prairie acacia
- Cassia - larval Multiple
- Diphysa robinoides - larval
Life Cycle
. green with creamy or stripe and yellow stripe. Three to four per year. Males all day seeking females.
Behavior
Males open areas and hilltops throughout daylight hours seeking females. Exhibits ' ' mating system where males compete through aerial pursuit and vertical spiraling when multiple males encounter the same female.
Ecological Role
of flowers as . function as on leguminous plants.
Human Relevance
Occasional garden visitor in southwestern United States; of minor interest to watchers due to distinctive pattern and seasonal color variation.
Similar Taxa
- Eurema boisduvalianaSmaller and brighter ; male has weaker 'dog ' pattern; female has reduced black on upperside; less sharply pointed.
- Eurema salomeBrighter ; more limited black on upperside; underside has round reddish spot near trailing edge.
More Details
Etymology
The 'wolf- sulphur' and alternative 'dog-face' pattern reference refer to the resemblance of the black border pattern to a canine face.
Phenotypic plasticity
Seasonal produces summer individuals with pale undersides and winter individuals with reddish or pinkish undersides, an likely related to or against different seasonal backgrounds.