Occasionally one may peer into the grass and see something that makes one wonder why evolution has gone down a particular route. A recent walk across the Firehills found a brightly coloured wasp sporting some interesting accoutrements. Hanging below its face were a pair of globular things that seemed to defy logic. They are the swollen tips of the maxillary palps, but their size would suggest that they must have some purpose. Speculation is rarely wise, but in this case one might speculate that the globular things could perhaps be involved in the detection of pheromones. The wasp is a male Halticoptera hippeus of the family Pteromalidae, it is one of the Chalcid wasps that are parasitoids of insect eggs.
A walk through the quarry in glorious June sunshine was enriched by the sight of a Bishop’s Mitre shieldbug stumbling and clambering through the rabbit-cropped turf. This species of shieldbug is one of the easiest to identify from its distinctive shape, yet it has proved elusive in the Country Park until now.
The visit was also fortunate to find a couple of flightless wasps that hunt prey by jumping onto them. This species of wasp Dinocarsis hemiptera was found last year in the rush growing in the seasonal pond of the quarry, but this visit found them in Sheep’s Sorrel growing in the area so well cleared by volunteers in former times.
Hawthorn blossom can now be seen all over the Country Park and a good place to see it is in the Quarry.
Also in the Quarry can be seen a carpet of Sheep’s Sorrel in bloom where we cut the gorse near the large rock.
If you head along the causeway from the visitor centre toward the quarry but turn left before descending the uneven rock cut steps, you will find yourself on the edge of Coastguard Lane Field. There is a very stunted, scrubby little oak by the path that goes unnoticed most of the time, but a very close look into its unfurling leaves has found a new species for the Country Park. Holarcticesa clinius (formerly Grahamis clinius) is a parasitic wasp of the family Eulophidae and subfamily Entedontinae, and is approximately 1.5mm long.
Right now is a very good time to visit Brakey Bank. There are Bluebells, Red Campion, Greater Stitchwort and Yellow Archangel all out in flower. To coincide like this does not happen every year, so is well worth a look. There is some Lesser Celandine just hanging on as well. Highlight for me this morning was finding 2 White Campion plants just by the footpath. I do not recall seeing it there before.
I think that everyone that I met yesterday was agreed that it was not much of a day, so it was quite a surprise for the sun to make an appearance late in the afternoon and we were treated to the unusual sight of a rainbow on the Firehills. Shortly, along came the Coastguard helicopter and my fellow dog walkers speculated that they must be out looking for the pot of gold!
There is a scrubby sallow growing on the seaward side of the hibernaculum in Coastguard Field. Giving it close examination recently discovered a tiny (1.5mm long) parasitic wasp lurking within its branches. It was a Diglyphus isaea, a species that is commercially available as a biological control for several species of leafminer. An adult wasp will seek out the larvae that create leaf mines (in Chrysanthemums for example) and lay eggs in the leaf mining larva. The process will kill the leaf mining larva, and the emerging wasp larva then uses the leaf mining larva as food. While this might sound like a grisly process, it is entirely natural behaviour that has been utilised for commercial benefit. Introduction of such species as Diglyphus isaea into commercial glasshouses gives opportunity for escape into the natural environment, and the one found in Coastguard Field will have originated this way. As to how many generations of parasitoid have passed between the introduction and this discovery can never be known, but it is another new record for the Country Park.