Leaf colour patterns, vegetative and sexual reproduction of Episcia ...

Figure 15 Episcia lilacina; Alticinae beetles browse
one flower.
Discussion: The evolutionary competition between forage plant and butterfly is not only
fought with chemical weapons, but also with optical deception and camouflage (Gilbert 1982).
Females of the heliconiine butterfly are geared by the leaf form of their specific forage plant for
the placement of their eggs. Thus, with time, a plenty of leaf forms developed that appeared to be
grazed or full with eggs (Lunau 2002).
There could be similarities between the strategy of the family of Passifloraceae and Episcia
lilacina. The different colouration of the leaves could be a simulation of grazed leaves (Fig. 14).
The attacking insects are misled by the contrasty colouration. But the results show that the
hypothesis of leaf mimicry cannot be proved. The found species of beetles seems to limit its
foraging to the flowers. Thus leaves only one species of butterflies to feed on the plant. There are
rarely traces of feeding damage on both leaves and flowers. Most notably, no difference between
the various leaf-types could be observed. No locations totally grazed by vermin could ever be
found. Most likely, there are some kinds of chemical repellents present in the leaves. They are
heavily pilose, probably, to avoid being eaten (Schaller 2002). In addition, there are few amongst
the types of leaves that look actually grazed.
As a conclusion it can be said that the cause for the diverse leaf patterns is not to appear
grazed to attackers. Relating to this, a tendency towards a certain pattern would be recognizable.
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