If you make souvenirs then adding the species is a nice touch.
If you make art/craft then don't make it look like a souvenir by writing the species on it. Ever seen a Monet painting with "Oil Paint" added just below his signature?
I do provide a customised ticket that carries relevant information with each individual piece. An extra effort but worth the effort I think.
Ticket - Front View.doc
Ticket - Rear View.doc
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