I inadvertently found one of these black and gold beetles late last month. Regrettably, I didn't realise it at the time. I casually snapped a photograph of a wasp on a honeydew scale infested black beech tree while in Hanmer. I wanted to know which Vespula wasps were in the area. I only realised after I got home that there was a amazing beetle on the same trunk. I posted my observation to NatureWatch NZ as Coleoptera, "ID Please", as I had no idea what it was. Stephen recognised it and identified it less than a day after I posted my observation.
The one photo I inadvertently took of my first Mitophyllus foveolatus. It's to the left of the wasp.
Photo by Jon Sullivan
Famous New Zealand entomologist (and inventor of daylight savings) George Vernon Hudson, wrote in 1934 that Mitophyllus foveolatus was common on Mount Arthur in northwest Nelson "and thought it was probably attached to alpine beeches" (Holloway 2007). Stephen speculates that they may feed on the honeydew on the beech trees. This raises the ominous possibility that few people have seen these beetles in recent decades because of competition with the exotic Vespula wasps that now plague New Zealand beech forests and monopolise the beech honeydew.
Or, perhaps, hopefully, it's just that not enough people are out looking in the right places and the right times to see these beetles. This is where you come in. If you are out and about in the South Island high country, keep an eye out on the black sooty honeydew covered beech trunks for these distinctive little flecks of beetle gold.