Category: insects (Page 41 of 88)

Bug of the Week: Eastern Yellow Jacket

In Arizona, we have more than our share of stinging arthropods and prickly plants.

yellow-jacket-101

We do not, however, have any of these wasps in the low desert.

yellow-jacket-wasp-vespula

This yellow and black wasp is the Eastern yellow jacket, Vespula maculifrons. You can identify it by its relatively small size (smaller than other yellow jackets) and the anchor-shaped marking on the first tergite (first dorsal plate on the back of the abdomen, near the thorax).

eastern-yellw-jacket-vespula

The Eastern yellow jackets are found throughout eastern North America. They nest under the ground or sometimes in houses. They have even been known to nest in between bales of hay in a barn. Under the cover of the ground or other material, yellow jackets’ nests are made of a papery material similar to that of the white-faced hornet, which are more likely to be visible because the white-faced hornets nest in the open.

wasp-nest

Yellow jackets are social insects, with colonies divided into queen and worker individuals. Unlike honey bees, yellow jackets do not overwinter as a colony. Instead, only founding queens overwinter. Each spring a queen starts a new nest by laying eggs that become worker wasps, which in turn raise more and more workers in the cells of the papery nest. Eventually the queen starts laying eggs that become more queens or males, as well.  The numbers of yellow jackets are highest in the fall.

The worker wasps feed the larvae food ranging from pieces of insects such as caterpillars to bits of luncheon meat in a picnic sandwich. As you can see in the photographs above, the adults also feed on nectar from flowers.

Have you ever seen yellow jackets processing a caterpillar or luncheon meat by chewing off manageable-sized pieces? It can be quite fascinating to watch.

Do you see yellow jackets where you live?

Bug of the Week: Thurber’s Cotton and Ants

Yesterday we introduced the lovely plant, Thurber’s cotton, Gossypium thurberi.

While I was taking photographs of the plant, I noticed some ants.

ant-on-flower-petal-2These kind of ants are called rover ants. They are not very big. What are they doing on the plant?

ant-visiting-floral-nectaryHere’s one in the flower. It is visiting the nectar-producing area or “floral nectary.”

ants-at-EFNs-darkThe rover ants were also visiting an area under the flowers, on the sepals. Any ideas why?

ant-visiting-EFN-33Having some experience with cotton plants, I  realized the ants were visiting some nectar-producing areas there as well. Nectaries outside the flower proper are called “extrafloral nectaries.” See that dimpled area the ant is facing? That is an extrafloral nectary.

ants-at-EFN-multipleAs you can see, the extrafloral nectaries on the plant were very popular.

Many different plants produce nectar in various extrafloral nectaries and most of them attract ants and small wasps.

The most commonly-reported reason that plants have these structures is that the nectaries attract predators and parasites, which in turn attack the eggs and larvae of plant-feeding insects they encounter.

Have you ever seen ants visiting nectaries on plants? What kind of plant was it?

Bug of the Week: What is In the Yard

What sort of insect activity did the recent rains and high humidity bring out?

slender-bee-fly-geron1. A slender bee fly, genus Geron

moth-with-spots2. A brightly-marked moth, out in full daylight

snout-butterfly3. Yay, the snout butterflies are back!

Fall is the time when we usually have a lot of caterpillars. We’ll have to see if this is a good year for them.

 

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