The Daily Bucket is a regular feature of the Backyard Science group. It is a place to note any observations you have made of the world around you. Insects, weather, meteorites, climate, birds and/or flowers. All are worthy additions to the bucket. Please let us know what is going on around you in a comment. Include, as close as is comfortable for you, where you are located. Each note is a record that we can refer to in the future as we try to understand the patterns that are quietly unwinding around us.
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Tallahassee, Florida
Almost two weeks ago I noticed an odd cluster of insects on our front rail early in the morning. I was in a hurry to head to work and didn't investigate closely.
When I got home Ms Mole and her collaborator/house guest reported seeing and photographing these odd insects which they had been unable to identify even to order.
Looking at the photos I realized that they were a species of 'bark louse' (Order Psocoptera, also called book lice). Previously I had found one when black lighting and foresterbob had pointed me in the right direction.
What we had was an aggregation of Cerastipsocus venosus, a fairly common psocopteran of eastern North America. They are a very attractive looking insect with beautifully sculptured wings, even if their heads are bit funny looking.
The next morning they were back in the same spot and I got my own photos.
Their habit of occurring in groups containing both adults and nymphs (the wingless banded ones) and moving about as a unit has led to the unlikely and rather whimsical name of 'bark cattle' with 'tree cattle' given as alternative name. Like cattle they are grazers, feeding on lichen, algae, and organic debris. Our railings are a rich feeding ground for them as you can see. A good excuse not to clean the railings (as you can see when don't need an excuse).
Apparently they are not rare, although I have only seen this species once before. I'll definitely be on the look out for them in the future.
Addendum: The lice are a group of insects whose taxonomy has changed considerably in recent years. Traditionally the lice were divided into three orders: Mallophaga (chewing lice), Anoplura (sucking lice), and Psocoptera (non-parasitic lice). The Anoplura are all parasites of mammals (including humans) while the Mallophaga are primarily bird parasites with some species attacking mammals (including dogs and other domesticated animals but not human). It is now recognized that the Anoplura are actually nested within the Mallophaga and that the parasitic lice represent a single evolutionary line nested within the Psocoptera. So they are all now lumped into one large order which bug guide calls the Psocodea. At a glance lice seem 'over-classified' relative to other insects. There are only about 340 species of Psocoptera in North America which are divided up into a couple of dozen families. In contrast, the largest insect family in North America, the ichneumonid wasps, has 5000 named species living on our continent. Not being very familiar with this group, the large number of families could be the result of them being highly variable for the size of the order or that historically this group was studied by someone who was a 'splitter' (i.e. fond of subdividing into smaller groups).