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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I've been working on insect IDs off and on for the last week. Still more to go. I thought I would present a preview of two species I found last weekend coming to my light that are interesting for very different reasons.
The first insect is this male field cricket (family Gryllidae, subfamily Gryllinae). It is a member of the genus Gryllus but distinguishing species is very difficult. Field crickets are very well studied insects. This photo illustrates two reasons of interest. This cricket is calling (as the sound was low my guess is that the cricket was confused by the light and giving a courtship call).
Hopefully you can see that the forewings have a sculptured appearance. This sculpturing indicates a male because it is the apparatus for generating and amplifying the sound. The forewings are also slightly blurred because they are raised about the back of the insect and are vibrating against one another.
The song produced by crickets has been a source of fascination for biologists (including the husband of kossack, TexMex) for many decades. Males produces calls that attract females, they also produce aggressive calls when encountering other males, and softer calls when females are in close proximity. Studies of neurobiology, sexual selection, and many other fields have been made using crickets as model organisms.
The other thing to note is that the hindwings of this cricket are very long (the wings are membranous and extend out from under the forewings). This is a long-winged morph individual of this species. It is capable of flight. In may cricket species (and other insects) there are often a long-winged morph and a short-winged morph which is flightless. Understanding the costs and benefits of the two morphs and mechanisms controlling their persistence is an important set of questions in evolutionary ecology.
Gryllus species are all very similar to one another and the number of species, especially in the southern part of the US has long been in doubt. Over the last several decades it has been found that the number of species is much larger than originally thought. It is amazing realize that such a well studied group of insects had so many unrecognized species in North America.
The second insect is a Pleasing Lacewing Nallachius americanus. It is one of only two species in the Dilaridae (Pleasing Lacewing family) in North America.
In contrast to the crickets these insects are almost completely unknown. This individual is also a male because, according to my reading, the females have an enlarged ovipositor (egg-laying structure) which this individual does not have. Other than that there seems to be almost nothing known about these insects. The larvae are elongate and live under bark. Like other members of the order Neuroptera the larvae are predators (think ant lions). And that's about it. I have no idea where the name 'Pleasing' came from.
I was able to identify this to species fairly easily because it is a member of a small family in a relatively small order. So narrowing it down was fairly simple. There are innumerable species of small beetles, flies, wasps, and moths about which equally little is known that would be much harder to ID because they belong to enormous orders and families.
So my main point is that both of these insects, one well known to everyone and a scientific model, the other an incredibly obscure drab tiny insect, both illustrate how little we actually know of the details of the natural world. And that's really important because we are likely to lose a substantial number of species permanently from the earth in the coming decades. And to misquote Joni Mitchell - you can't know what you've got after it's gone.
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