Butterflies of the
Amazon and Andes
Family - RIODINIDAE
subfamily - RIODININAE
Tribe - RIODININI
Tatama NP, Colombia
© Adrian Hoskins
There are 1324 known species of
Riodinidae in the neotropical region, 121 of which are placed in the
genus Mesosemia, and a further 8 in the
closely related Semomesia.
Butterflies of both genera are commonly known as Eyemarks, due to
the prominent ocelli located in the discal cell of the forewings.
All Mesosemia and
Semomesia species are sexually dimorphic. The males of many
are metallic blue, marked with fine black lines and a black apex,
while their females are typically dark brown, and often marked with
prominent white bands. In most species there is a series of fine
wavy black submarginal lines on the hindwings.
Mesosemia pacifica is only known from
This species is found in undisturbed cloudforest at elevations
between about 1000-2000m.
I have no data regarding pacifica but
the lifecycle is likely to be similar to that of other
Mesosemia species as follows: The eggs
are white and laid singly on stems or on the undersides of leaves.
The foodplants include Psychotria,
Cephalanthus and other understorey
Rubiaceae. The larvae are dull green, plump and slightly flattened.
They have a series of flattened lateral lobes below the spiracles,
and tufts of short stiff setae on the back and sides.
Males are usually seen singly, but
sometimes several can be found flying together in places where trees
have fallen and created small light gaps in the forest. The
butterflies have a rapid and erratic flight. They settle frequently on
the uppersides of leaves. After landing they immediately proceed to
walk about over the leaf, always holding their wings half open.
Females are seen much more rarely, usually when flitting about just
above the herb layer in search of oviposition sites.