June 6, 2016

Few creatures possess scientific names as memorable as the members of a small genus of day-flying moths called Notoreas. Quite apart from their attention-grabbing title, several colourful species of Notoreas hold particular interest for me, due to their association with some of our ‘native daphnes’ (Pimelea spp.). On several occasions, I have looked for this moth whilst observing populations of Pimelea in various parts of the country, including the southern Taranaki coastline, dunes near Bluff (where a species with the brilliant title of Notoreas casanova is found) and at Karioitahi Beach near Auckland.

However, my timing had always been off until a field trip to Pencarrow Lakes (near Wellington), as part of my lecturing work with Victoria University of Wellington. The coastal species of Notoreas generally have two periods of adults appearing within a summer, which fall either side of mid-summer, and it was in late summer that we walked along the shingle dune terraces that separate Lake Kohangapiripiri from the sea.

Along these dune terraces, there are extensive mosaics of scabweed (Raoulia hookeri) and two species of Pimelea – one of which is listed as P. urvilleana (a species that conforms to the flat-growing plant above) and the other is similar to Pimelea villosa (which is closer to the Pimelea shown below). It was towards the end of our time wandering along the dune terraces (and sketching, in the case of the students) that I saw an agile, orange and black moth flit past me. Having followed it for a couple of metres, professional duty prevented me from being able to pursue it further to get a photograph, as just at that point a student had a question about the surrounding vegetation.

Having climbed over the hill and down into the valley between Lake Kohangatera and Lake Kohangapiripiri, we were greeted by the sight of enormous numbers of toetoe (Austroderia toetoe) occupying the wetlands that extend for a long way both north and south. It was heartening to see pure stands of toetoe, in contrast to the place that the exotic pampas now inhabits in many other wild places.

On the margins of Lake Kohangapiripiri, we stopped in an area with several ecotones, as it was a good space for students to observe a variety of habitats (and the aesthetics associated with those). It was here that I had the chance to see a relatively rare native herb that I had never seen in the wild, Eryngium vesiculosum.

This compact species of sea holly is of particular interest to me, due to the fact that we have previously planted an exotic species of sea holly, Eryngium planum, in urban gardens, where its metallic purple flowers and slightly spiky stems bring an unusual character. Our native species, which has been sold for cultivation before (by Oratia Native Plant Nursery), shares that metallic blue-silver colour, whilst also exhibiting other similarities to E. planum (albeit in a creeping, more diminutive form).