Butterflies of the
Amazon and Andes
Mexican
Grass Yellow
Eurema mexicana
BOISDUVAL, 1836
Family - PIERIDAE
subfamily - COLIADINAE
Eurema
mexicana � Tony
Hoare
Introduction
The
genus
Eurema was until fairly recently
represented in the neotropics by about 30 species, but several have
now been reclassified as Pyrisitia,
leaving a total of 19 currently recognised species in the
neotropical region. Elsewhere in the world the genus has 9 species
in Africa, 2 in Madagascar, and 9 in the Oriental and Australian
regions.
These smallish butterflies are characterised by
having yellow or white uppersides, with dark apical markings. The
forewings have a strongly curved costa and a squarish apex. In most
species the hindwings are rounded, but in
salome, mexicana and
arbela the termen is projected to a
point.
The various species can be told apart by the
pattern of mottled dark markings on the underside hindwings, and by
the black borders on the upperside forewings, which differ according
to species.
Eurema mexicana is distributed from the south-western states
of the USA to Colombia.
Habitats
This species can be found in deciduous forest, acacia scrubland, and
along roadsides and riverbanks at elevations between sea level and
about 2000m.
Lifecycle
The egg is white and is laid singly on the upperside of leaves of
the foodplants Diphysa,
Cassia and Acacia
( Fabaceae ). The fully grown larva is yellowish-green, with has a
broken red lateral line that is edged above and below with pale
yellow. The pupa is yellowish-green. It is typical of Coliadinae,
with an arched abdomen and large projecting wing-pads; and is
attached by the cremaster and a silken girdle to a woody stem of the
foodplant or nearby plant.
Adult behaviour
Males
are usually found singly, or occasionally in two's or three's, when
imbibing dissolved minerals from damp ground at the edge of ditches,
runnels or roadside banks in forested areas.
Females
are more often seen nectaring at flowers along roadsides and
riverbanks, or when exploring forest-edge habitats in search of
egg-laying sites.
The flight is fluttery but rapid.
|