For the identification of insects and other fauna and flora of South Africa: please click on the following links:
Insects and related species: Antlions - Ants - Bees - Beetles - Bugs - Butterflies, Moths and Caterpillars - Centipedes and Millipedes - Cockroaches - Crickets - Dragonflies and Damselflies - Grasshoppers and Katydids - Mantis - Stick Insects - Ticks and Mites - Wasps - Woodlice
Plants, Trees, Flowers: (Note: Unless plants fall into a specific species such as Cacti, they have been classified by their flower colour to make them easier to find) Bonsai - Cacti, Succulents, Aloes, Euplorbia - Ferns and Cycads - Flowers - Fungi, Lichen and Moss - Grass - Trees
Animals, Birds, Reptiles etc.: Animals, Birds, Fish and Crabs - Frogs - Lizards - Scorpions - Snails and Slugs - Snakes - Spiders - Tortoise, Turtles and Terrapins - Whipscorpions
Other photography: Aeroplanes - Cars and Bikes - Travel - Sunrise - Water drops/falls - Sudwala and Sterkfontein Caves etc.

Videos: YouTube

Saturday, July 10, 2010

Insect antennae

Antennae function almost exclusively in sensory perception. Some of the information that can be detected by insect antennae includes: motion and orientation, odor, sound, humidity, and a variety of chemical cues.
The antennae are an insects primary, non-visual, sense organs, though in a few rare instances they have become adapted for other purposes such as seizing prey items ( i.e. the larva of Chaoborus sp. {Diptera}) or holding females during mating (i.e. the males of Meloe sp. {Coleoptera}) Not all insects possess antennae, they are absent from the Protura.
In most insects the antennae possesses a mechanosensory organ on the pedicel (the second antennal segment) called 'Johnston's organ' and, normally, only the basal antennal segment contains intrinsic muscles. However in two orders (Diplura and Collembola) the antennae lack a 'Johnston's organ' and all but the last segment contains intrinsic muscles, thus allowing far greater controlled movement of the antennae as is demonstrated by the rolling and unrolling of the antennae observed in the Collembola Tomocerus longicornus.
Antennae come in a wide variety of shapes and sizes, generally the first segment is known as the 'scape', second segment as the 'pedicel' and the rest as the flagellum. It is quite usual that the males of a species have more elaborate antennae than the females, this is because it is normally the males who have to find the females. The greater the surface area of the antennae the more dilute scents they can detect, thus male insects with feathery antennae, such as those seen in many moths, are far more sensitive than the purely filamentous ones of crickets and cockroaches.
The antennae are a pair of sense organs located near the front of an insect's head capsule. Although commonly called "feelers", the antennae are much more than just tactile receptors. They are usually covered with olfactory receptors that can detect odor molecules in the air (the sense of smell).
Many insects also use their antennae as humidity sensors, to detect changes in the concentration of water vapor. Mosquitoes detect sounds with their antennae, and many flies use theirs to gauge air speed while they are in flight.

28 comments:

Max-e said...

Hi Joan, been enjoying browsing though your latest posts. You have some amazing shots. I really like this series on the moths. It is so easy to dismiss these drab looking creatures and yet they are quite beautiful, in their own way.

SAPhotographs (Joan) said...

Hello Max. It is always a pleasure to hear from you again.

Thanks, I am glad you like the posts as they are somewhat different and a side of nature one does not see often.

You are right, some moths are extremely beautiful but we tend to only see the drab brown ones around. This summer I will be hunting them at night and so hope to come up with many more interesting species which use the darkness to hide away in. :)

Food, Fun and Life in the Charente said...

What an interesting post Joan, I knew almost none of that information. I always wondered why those little buzzer things you plug into the wall kept the mosquitoes away:) Diane

Gaelyn said...

The moth's antennae look so much like delicate feathers. It's amazing how much they can Do with them. Hmmm, I'd like to have them as well.

JM said...

These are outstanding, Joan! Amazing macro shots indeed! The third image reminds me of one of those Samba girls at the Rio de Janeiro Carnival! :-)))

SAPhotographs (Joan) said...

Thanks Diane. Now you know how we develop technology. :)

SAPhotographs (Joan) said...

Me too Gaelyn, they will come in very useful. :)

SAPhotographs (Joan) said...

Thanks Jose. Do they still use fans/feathers for their dances? :)

A human kind of human said...

Mozzies has antennae? As always, your photos are amazing. Don't you think it is time to come and snap some moths here in the Bushveldt
(hint, hint). I know we owe you one but I promise we will make up... soon.

Becky and Gary said...

Very, very interesting Joan. I guess I never thought about what antennae can really do for an insect. What awesome images too. Perfect!
B.

Vagabonde said...

Your posts are so informative. I learnt a lot on herbs, insects and flowers by reading your last several posts. Very nice.

ramblingwoods.com said...

This is great info for me as I am just starting to hear the summer insects and hope to get photos...Loved this post...Michelle

Mary said...

Those are some really fancy antenae! You get such great shots of stuff like this and know so much information. Great post!

SAPhotographs (Joan) said...

Hello Anne. Just yesterday I was thinking about you. :) I promise as soon as it warms up I will be over there for a weekend again but when it is cold like this, I prefer my own bed. :)

SAPhotographs (Joan) said...

Thanks Becky. Yes, these are questions we never really ask ourselves and like evrything else, there is always a good reason for them.:)

SAPhotographs (Joan) said...

Thanks Vagabonde. Lovely to hear from you again.

SAPhotographs (Joan) said...

I hope you get lots of insects too Michelle as you know how I love to see them. Here it is quite still at night and I am counting the days till summer again.

SAPhotographs (Joan) said...

Thanks Mary. I have been learning so much in the past few months and come across such wonderful information I want to share.

This Is My Blog - fishing guy said...

Joan: What a super look at the feathery antennas. I never saw mosquito antenna.

Craig Glenn said...

Nice series Joan! Love the detail.

Craig Glenn

SAPhotographs (Joan) said...

Thanks Tom. These in the picture are midges.

SAPhotographs (Joan) said...

Thanks Craig. I need to get out and take some more pictures close-up like this.

Philip said...

So now a question why don't the mosquitoes like Tabbard do they smell it or taste or what I like to know the answer to that one Mr's BUG LADY.
Great post by the way very interesting :)))

Firefly said...

It always kind of look like they have feathers in their mouths when you look at them from above. Great closeups. *sob sob, I want a DSLR with a makro lense*

Lynda said...

Joan, your macro photos just keep getting better and better. These are amazing! I feel very guilty that I never pay much attention to bugs.

SAPhotographs (Joan) said...

Here is a better one Philip, take some khakibos and hang it at your windowns. Even when dry, it keeps mozzies away. :) In the case of Tabbard, have you ever noticed how they bit you just in the spot where you forgot to put some on? LOL!! So no, it is not the smell in this case which puts them off. So in conclusion, those little things you plug in your wall socket and khakibos are best by far. LOL!!

SAPhotographs (Joan) said...

Only the bottom pic was taken with the macro lens Jonker, the rest with my P&S so dont "want" a DSLR too much. :) A lot depends on the P&S you have but the trick with all these cameras is holding it steady. A macro lens is MUCH more sensitive to the slightest movement and I actually hate taking pictures with it. LOL!!

SAPhotographs (Joan) said...

Thanks so much Lynda but dont feel guilty. Until I started taking macro pictures, insects were just annoying things which buzzed around me. :)