The Lensis Butterfly is an agent for both Creatures 3 and Docking Station.
They are classified as a bug and can be found on Eemfoo.org. They are perfectly safe to eat (highly recommended for Draconian Norns) and can be very beautiful fluttering about in your world.
In Docking Station, injecting this agent will create four of these butterflies in the upper level of the Norn Meso. It is highly recommended that you have plenty of plants available and growing, otherwise the caterpillars will have nothing to eat and won't change into more butterflies. If the number of butterflies drops below four, they will be recreated in the Meso.
Here's the description from TwilightCat's page: "Another breed of butterfly. This is pretty much like the Inkras and Okirons only a little slower and larger. Needs plants for the caterpillars to grow into butterflies."
See also the Okiron Butterflies and the Inkras Butterflies.