Tag Archives: Bugs on flowers

Flower Power

7 Jun
An orchid mantis on flowers.

An mantis lurks on flowers, awaiting prey.

I found this flower mantid doing as it’s name might suggest in Argentina.  The most well known flower mantis is the Malaysian orchid mantis, a striking pink flower-mimic.  These particular flowers were buzzing with insect activity, so this mantis had found a good hunting spot.

Like many insects which lack a pupal stage (such as a cocoon or chrysalis), immature and mature mantises can be distinguished by the development of the wings. In this juvenile mantis (called a nymph), the two pairs of partially developed wings are visible as ‘wing pads’ just before the down-turned abdomen.  The wings will only be fully formed after the final shedding of the exoskeleton as the mantis achieves its final adult form.  Only adult insects have wings, although some species, such as worker ants, walking sticks, and burrowing roaches have become secondarily wingless in the adult form.

Here’s another shot.

Stick Mimic

31 May
A stick grasshopper on a flower.

A stick grasshopper on a flower.

Look twice.  That’s not a stick.  It’s not even a walking stick.  It’s a grasshopper!

The stick grasshoppers comprise the family Proscopiidae, and are unique to South America.  Aside from their jumping hind legs, their heads are very distinct from that of a walking stick: elongate, with a mouth near the bendable neck, and eyes further along the length of the head.

These guys were all over Argentina and fun to watch.  This particular fellow was posing on a flower all by himself, so I had to snap a picture.  Here’s another stick hopper, this one particularly cryptic:

A well-camouflaged stick grasshopper in Argentina (Proscopiidae).

A well-camouflaged stick grasshopper in Argentina (Proscopiidae).

To Bee or Not to Bee

28 May
A bee-mimicking hover fly visits a flower.

A bee-mimicking hover fly visits a flower in Argentina.

If you thought this was a picture of a bee, look closer.  A few key characters will give this mimic away.  Bulging, compound eyes take up most of the head.  The antennae are two short stunted nubs at the front of the head between the eyes.  The ‘waist’ or connection between thorax and abdomen is broad not narrow.  And most diagnostically, flies have only one pair of wings, not two — the hind wings being modified into two short knob-like structures used as counterweights in flight.  Thus the fly order name Diptera, “two wings” (two wings make up one pair).

This particular fly is a member of the genus Syrphidae, the hover flies or flower flies.  Many members of this group are bee or wasp mimics, as well as important pollinators of flowers.  As their name suggests, these flies are especially well adapted at hovering (aiding in flower visitation)  a skill which the males of some species use to impress females.  Such males stake out a spot in the air and attempt to remain ‘motionless’– an impressive feat for a tiny insect easily buffeted by wind currents.  The male who best holds his postion for the longest period of time is considered the sexiest.  The BBC series Life in the Undergrowth has an excellent segment on this behavior.

Ambushed Wasp – The Ambush Bug

13 Mar

Wasp and ambush bug on flower.

An ambush bug preys on an unwary wasp.

Exploring an Argentinean roadside I spotted what I thought was a dead wasp on a flower.   Wondering how this wasp had come to perish so abruptly in her nectar gathering work, I looked closer.  I actually poked at her several times before I noticed the second occupant of the flower—an ambush bug enjoying a tasty wasp meal!

Ambush bugs are a subfamily of Assassin bugs, family Reduviidae.  Ambush bugs are “sit-and-wait” predators.  These highly cryptic (camouflaged) insects frequently lurk around flowers, where they pick off unwary visitors.  They have mantis-like raptorial forelegs to snatch their prey from a safe distance.   Like other true bugs (order Hemiptera, suborder Heteroptera) ambush bugs have a segmented tube-like ‘beak’ for feeding.  Ambush bugs insert this beak into a weak spot in their prey’s hard exoskeleton and suck out the fluids.