Archive | March, 2011

Tools for Insect Collecting

28 Mar
Pinned beetles in a collection box (Coleoptera).

Pinned beetles in a collection box (Coleoptera).

New page up in the techniques section.  Please check out my “Tools for Insect Collecting.”

For the novice bug enthusiast interested in starting an insect collection the options and information available can be bewildering.  Luckily, the hobby is easier (and cheaper) than it might seem.  Here’s my two-cents worth on the best tools to get you started.

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For more techniques for insect collection and rearing, visit the techniques section.

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Among the Clover – Aquatic Grasshoppers?

17 Mar
A crested lubber grasshopper (Xyleus sp.) in Argentina.

A crested grasshopper (Xyleus sp.) in a flooded clover field along the Paraná river.

Happy St. Patrick’s Day! (And happy birthday to my brother, Eric.)

The grasshopper above is a member of the lubber family Romaleidae, genus Xyleus, a crested grasshopper.  We encountered a number of these large fellows doing field work in Argentina last year.  While we were there, frequent rains caused flooding in most of our field sites along the Paraná river.  This made working with fire ants difficult.  In one notable instance we returned to a line of sugar baits the following day and found tadpoles swimming around them.  Not optimal for a fire ant foraging study.  We also got to observe lots of insects coping with (and flourishing in) the flooded conditions, as in the case of the grasshopper pictured feeding half underwater below.

Thanks to Paul Lenhart for photos, IDs, and being awesome!

Rhammatocerus sp. grasshopper feeding in a flooded field.

Rhammatocerus sp. grasshopper feeding in a flooded field along the Paraná.

Frog Tongues, Vader Masks, and Dragonfly Nymphs

4 Mar
The extended spoon-shaped labium of a libellulid dragonfly nymph.

The extended spoon-shaped labium of a libellulid dragonfly nymph.

One of my favorite examples of weird insect anatomy are the strange mouthparts of the aquatic nymphs of dragonflies and damselflies.  A close look at the faces of these creatures reveals large hinged structure folded back under the head.  In the case of the nymphs of Libellulidae, this structure actually curves up and wraps around the face, very much like a Darth Vader style mask.  What are these structures?

Ventral side of libellulid nymph.

Ventral side of libellulid dragonfly nymph, showing the spoon-shaped labial mask.

All Odonata larvae have a prehensile labium, sometimes called a labial mask, which folds under the head and thorax.  This lower lip is capable of extending rapidly forward, striking prey before they can react.  Hooks on the ends snag the prey and draw it back to the mandibles.  All in all, the feature is reminiscent of a frog tongue snatching flies.

Ventral side of aeshnid nymph.

Ventral side of aeshnid dragonfly nymph, showing the flat, blunt labial mask.