#Coelostomidiidae

[drhoz]

#2546-2548 - Sooty Beech Scale, Sooty Beech Mold, and the Common European Yellowjacket

One of the features of the Antarctic Beech forests of New Zealand, particularly on the South Island, is the thick layer of what looks like black moss covering many of the trees. And the ground. And most of the plants in the understory.

The black moss is actually sooty mold, a complex combination of fungi from a variety of different Orders, thriving on the ludicrous amounts of honeydew pumped out by the Sooty Beech Scale Ultracoelostoma assimile. The white filaments sticking out of the mold in the first photo is the anal tube of the scale insects, the longest such tube of any insect. The insect is most abundant on Black Beech Nothofagus solandri (the black in the name is from the mold) and middle-aged trees may lose 80% of the sugars they make to them. Younger trees have smooth bark that doesn't offer safe nooks and crannies for the crawlers, and in mature trees the bark is too thick for the scale insects to drill through.

The honeydew is a keystone feature of the Nothofagus forests - birds, bats, reptiles and insects all feed on the honeydew. Some rely on it. There's at least two species of caterpillar that prey on the scale insects. And a beetle - the only one in its family - that feeds only on the sooty mold.

And then the wasps arrived.

Two species are the problem - Vespula vulgaris (see photo) and Vespula germanica. Both are now more common in the Nothofagus forests then they are anywhere else in the world, and by a horrifying degree. Not only are they getting a diet of pure rocket fuel for much of the year, they then denude the forest of invertebrate life to feed their larvae. By monopolising the honeydew supply they're starving the birds and other animals that need that food supply, especially since introduced mice, rats, and stoats are eating the fruit and seeds of the forest, or turning on the birds when they run out of mice.

St. Arnaud, Southern Alps, New Zealand

[onenicebugperday]

Great giant scale insect, Coelostomidia zealandica, Coelostomidiidae, Hemiptera

Shown are winged males mating with a large, flightless female. Found in New Zealand.

Photos by steve_kerr

[drhoz]

Day trip out for a swim in the river and a look at the New Zealand Honey Dew which is a sweet sap like liquid / honey produced by insects which reside in the Beech Trees of New Zealand. This makes an excellent Emergency Energey Source of Survival Food. Two species of beech tree inhabited by two species of honeydew insect (the sooty beech scales) from the Margarodidae family produce New Zealand's largest single exported honey crop. The beech trees are Black Beech (Nothofagus solandri) and Red Beech (N. fusca). The two insects are Ultracoelostoma assimileand U. brittini. U. brittini tends to inhabit the trunks and larger branches, while U. assimile is recorded (C.F.Morales) as favouring the upper branches and twigs, thus U.brittini is the insect most likely to be encountered by the casual observer wandering in the beech forests. The black colour of trees and plants with a honeydew source is due to the growth of a blackTubules from U.brittini with drops fo honeydew sooty mould (Capnodium fungus) on the surplus nectar exuding over the plant and sometimes even the ground. Particles of this fungus are typically found in honeydew being referred to as "honeydew elements" and are used as a part of the identification as honeydew. Droplets of nectar are highly visible to any observer visiting the beech forest, but bees are rarely seen collecting these. Mostly they are observed foraging on the bark and particularly at the base of the tubules extending from the scale insect buried under the bark.

[drhoz]

Just a little lesson about the New Zealand sooty beech scale insect (Ultracoelostoma assimile), the honeydew it produces, the sooty black fungus (Capnodium sp.) that grows on the honeydew, and the role that honeydew plays in the ecosystem of New Zealand beech forests. I also discuss how they are threatened by introduced common (Vespula vulgaris) and German (Vespula germanica) wasps. I'm a singer, songwriter and guitarist from Hamilton, New Zealand. My videos are a mix of music, and hiking the outdoors. Ceolskog is my folk metal / heavy metal / country rock (and some other genres) band. It is also the name given to this hiking and nature-themed YouTube channel. Ceol means music in Irish, and skog means forest Norwegian and Swedish. I don't have a Patreon, but if you're a regular viewer, and you want to support me some way, you can find my music on Spotify, Bandcamp, iTunes, Soundcloud, Amazon, and YouTube too (of course).