Thursday, May 19, 2011

Drosera peltata ex Grampians

Although this blog is supposed to be about Sarracenia, I have found myself posting about Drosera peltata more and more over the past few weeks! Although I find it often enough in the wild, the truth is I only grow one clone of this marvelous plant, and it is one from the Grampians in Victoria.

This clone is excellent because (i.) it is a huge plant, growing to 30-40 cm, (ii.) its golden colour is magnificent, (iii.) it will not rot if you leave it sitting in a Sarracenia water tray while dormant, (iv.) it is self-fertile, sowing itself through Sarracenia pots on its own and (v). even seedlings will take -6*C without  burning. This clone is apparantly widely grown by members of the VCPS, one of whom gave me an established pot last year. It is now coming up all through my Sarracenia collection unassisted. I am hopeful that it will become the weed Drosera of my collection - I am in the final throws of eradicating Drosera capensis. Why? Look below...

Drosera capensis unfortunately catch and kill these guys. This rather ornate little bug (as in true bug or Hemiptera) is an undescribed species of Setocoris, the sundew bug genus. Setocoris are rather enigmatic, in that there are three named species, another 150 species with unpublished manuscript names and an additional 75 species that are not yet well enough known to be named. My colony live on Drosera binata and orginated from a collector living very near wild D. binata in the Blue Mountains. A lot of people call Setocoris Assassin bugs, which is entomological heresy! Assassin bugs (family Reduviidae), although similar in appearance, are distant relatives of Setocoris, which belong to the Mirid bug family (Miridae). Sundew bugs as a name is far more descriptive. In term of ecology, they very probably act as a surrogate stomach to their parent plants, much in the same was as Pameridia bugs do for Roridula in South Africa. However, Setocoris also suck sap from their parent plants. As evidence, the D. binata my Setocoris live on was covered in small 'sting' marks consistent with Hemiptera feeding damage I have seen on a variety of fruits. Setocoris living on D. binata var. multifida 'extrema' in the wild on Stradbroke Island have also been observed to drink sap by a Queensland Museum entomologist, but this record was unfortunately published in a relatively obscure text on Australian insect ecology that no-one else seems to have referred to.