Showing posts with label weevil. Show all posts
Showing posts with label weevil. Show all posts

Wednesday, September 19, 2012

The weevil within

The hollyhock seed pods are drying up now and rings of holes have become visible around many of them.  I was not surprised to see these holes, since in the past weeks I have seen many bugs feeding on the seed pods.  What did surprise me was that quite a few holes had something protruding out.

Something is sticking out of one of those holes in the hollyhock seed pod.
Intrigued, I began peeling open a pod.  Inside, in addition to the hollyhock seeds, I found a large group of hollyhock weevils (Apion longirostre).  Once exposed, the weevils quickly dispersed in search of cover.

A hollyhock seed pod full of hollyhock weevils (Apion longirostre).
How had all those weevils gotten inside the seed pod?  Through holes -- but not the holes in the seed pod.  There were matching holes in the seeds themselves, and not all these holes were empty.  Several had the long snouts and antennae of yet more weevils sticking out.  I broke open the seed pictured below to reveal the weevil that had grown inside.

A hollyhock weevil (Apion longirostre) developing inside a hollyhock seed.
Earlier this summer, a female hollyhock weevil must have laid her eggs in the ovaries of the flower.  As the seeds developed, so did the weevil larvae, consuming the seeds from within before pupating and finally emerging as adults.

Thursday, September 13, 2012

We only come out at night

Recently, I have been seeing less and less green in the garden.  The weather has been very dry and is now getting cooler -- but these aren't the only problems that the plants have been facing.  They are also losing large portions of their leaves to hungry herbivores.

A rose leaf that has been damaged by an insect, possibly a leafcutting bee.
I wanted to know what was altering the leaves, often in quite interesting and aesthetically pleasing ways; however, during the day, the "artists" remained anonymous.  Searching again after dark, I found a very different garden.  Wherever I looked, there were earwigs (Forficula auricularia).  I may have seen over a hundred earwigs during a single tour of the garden -- and wherever I saw them, they were eating.

A European earwig (Forficula auricularia) eating the edge of a leaf.
Although by far the most numerous, the earwigs were not the only insects busy chewing up leaves.  I also found a couple of black vine weevils (Otiorhynchus sulcatus) feeding under the cover of darkness.

A black vine weevil (Otiorhynchus sulcatus) eating the edge of a leaf.
The weevil above was just getting started on its leaf when I found it.  It was startled by the camera and dropped to the ground (these weevils cannot fly).  However, other leaves nearby had not been so lucky.