Pollination by deceit and floral mimesis in Thelymitra antennifera (Orchidaceae)

Thelymitra antennifera is found to be a general mimic of the search image of other co-blooming yellow or cream-flowered species including members of the following genera:Hibbertia, Goodenia and, to a lesser extent, Helichrysum, Pimelia and Stackhousia. The most common pollinators are Lasioglossum (Chilalictus) spec. and the introduced Syrphus damaster (hover fly) as well as a solitary wasp, Eurys spec.-T. antennifera acts by deceit, involving opticals (yellow colour and pollen imitation) as well as olfactory (sweet odour) signals. Capsule production is low and density dependent, a situation demonstrated in other species which have evolved pollination syndromes involving deceitful mimicry.