9 replies to this topic

[Foogoo]

As the title says, any obvious signs? I'm assuming a dead giveaway would be the presence of majors in the Pheidole colony.

[drtrmiller]

Well yes, the big-headed majors.  But also you're comparing myrmicine ants to (most) non-myrmicine ants, which is about like comparing an apple to an orange.

 

Without going into the depth of detail with which others may care to elaborate, myrmicines (Pheidole) will have the petiole and postpetiole, whereas non-myrmicines (Linepithema) will have a single petiole.

 

Notice how the waist of the ant narrows and becomes two distinct segments in this Pheidole megacephala:

 

 

Whereas this Linepithema humile only has one small notch connecting the alitrunk to the gaster, which is probably not visible to the naked eye:

 

Edited by drtrmiller, November 7 2014 - 3:51 PM.

[Foogoo]

Let me rephrase my question: when I come home and see a trail of punk ants in my kitchen or in my garden, is there a quick way of telling whether they're Pheidole or Linepithema?

[drtrmiller]

You can differentiate them with the naked eye if you get one on your finger and examine it for a second.  Linepithema are notorious for trails indoors.  I'm not sure about Pheidole.

[dspdrew]

Pretty much what drtrmiller said is it. You don't really have to look for the nodes, but you will notice on myrmicines, the petiole is usually skinnier and longer, and bends upward slightly most of the time, so it will look like a much more noticeable waste on them. That's how I know right away when I look down at an ant whether it's a myrmicine, or one of the single-node subfamilies.

[Gregory2455]

HAHAHA! Comparing an apple to an orange! I though the subfamily that Linepithema are in have no petiole at all. Ant identification is the major thing I need to improve in. Also, @Foogoo even though Pheidole megacephala have recently been introduced to California, the area where you are in would probably not have them yet, as they are only existent around Costa Mesa, and those areas. Of course, I do not know much about the facts of P.megacephala in California.

[Foogoo]

HAHAHA! Comparing an apple to an orange! I though the subfamily that Linepithema are in have no petiole at all. Ant identification is the major thing I need to improve in. Also, @Foogoo even though Pheidole megacephala have recently been introduced to California, the area where you are in would probably not have them yet, as they are only existent around Costa Mesa, and those areas. Of course, I do not know much about the facts of P.megacephala in California.

 

Hm, interesting. I'm guessing Crematogaster can be differentiated by their heart-butts? Seems like most of the random small black ants I see around here are Linepithema, but I want to make sure I'm not mistaking them for any other species before I heartlessly flick them away or blast them with the hose.

[dspdrew]

If you start going "anting" outside the city a lot, you will pretty quickly learn to tell the difference between Argentine ants and other ants.

[Crystals]

Take a magnifying glass with you next time and see if it helps.  If you don't want to touch the ants, use a piece of kleenex.

It takes a bit, but honest, a year from now it will be no problem to tell a Pheidole from a Linepithema. 

[James C. Trager]

Minor P. megacephala workers are the same size as Argentine ant​ workers, but much shinier, and more yellowish brown than gray or blackish-brown. See them once side by side, and you'll never confuse them again (as long as you have your glasses on ).

See numerous P. megacephala pictures, including minors, here http://itp.lucidcent...egacephala.html

Edited by James C. Trager, November 8 2014 - 9:51 AM.