Friday 1 August 2014

Mantidflies

A couple weeks ago when I went to check my black light (for moths) first thing in the morning I noticed a Mantidfly on my trap (that's just a fancy word for a cotton sheet). I got pretty excited because I had only seen two previously, so I carefully moved it onto a more natural background to get some pictures:


I even remembered to take a video of it (seemed to be preening, possibly trying to rid itself of the piece of spider web). The video is nice because it gives a better sense of its true colours, as it was taken without the use of a flash:

As you can tell, I was pretty excited to find this Mantidfly. In my experience they are a rarely seen insect, but very cool to see. Not only are they bizarre-looking and generally rare or uncommon, they've got a pretty cool life history as well. I didn't know much about them before so did some research and came across this excellent paper by Rob and Syd Cannings. All of the following information comes from this paper and should be credited to the authors, not me.

Like many insects, Mantidflies (Order: Neuroptera; Family: Mantispidae) are at the northern edge of their range in Canada with only four species in all of the country (all of which are found in Ontario). Only one species, Climaciella brunnea (the "Wasp Mantidfly"), is relatively widespread. The Wasp Mantidfly is, you guessed it, a wasp mimic and is the only species I had seen (twice) before in Ontario:
Wasp Mantidfly at Deloro, Hastings on 15 June 2008
Wasp Mantidfly at Backus Woods, Norfolk on 3 July 2010
The Wasp Mantidfly is not only the most widespread species but the easiest to identify. It's fairly large and its body is striped brown and yellow similar to that of many species of wasp. The other three Canadian species are quite similar and require very good photos, preferably showing close-ups of the pronotum and the wings. My most recent observation is clearly one of the remaining three and judging from my photos, it looks to me like the pronotum is mostly smooth (lacks "numerous short setae over its entire length") which means it is one of the two Dicromantispa species.

The separation of those two species is done by the presence/absence of dark spots on the "wing tips and some crossveins of radial cells", which my specimen appears to lack. That puts the ID tentatively as Dicromantispa sayi. This is exciting because, according to the paper referenced above, this would be a (known) range extension for the species in Ontario, which, based on examined specimens, was restricted to the north shore of Lake Erie. I'm waiting to hear back from some folks who know more than I do to see if I can get that confirmed or find out more.

As I mentioned earlier, Mantidflies have a pretty cool life history. Their raptorial forearms give them away as predators as adults (feeding on a variety of other insects). As larvae, most develop in spider egg sacs where they feed busily on the individual spider eggs. In some species the larvae actively search out spider eggs sacs, but in others they board adult spiders and enter the egg sac during the construction phase. The eggs are stalked, similar to these Green Lacewing (Chrysopidae) eggs:
Green Lacewing eggs at Heidelberg, Waterloo, 12 August 2005

References:

Cannings, R.A. and S.G. Cannings. 2006. The Mantispidae (Insecta: Neuroptera) of Canada, with notes on morphology, ecology, and distribution. Canadian Entomologist 138: 531-544.

Bug guide Mantidfly (Mantispidae) page

Update: I received confirmation from Rob Cannings that my identification was correct. Apparently there was also a record of this species near Tweed, Hastings County last summer, so it is probably worth looking for south of the shield in southeastern Ontario.

6 comments:

  1. Hi! I was doing some research on mantidflies today after my boyfriend found one outside his work! We live in Vancouver. I assume from your blurb this means it is of the Climaciella brunnea variety (based on location) ?

    ReplyDelete
    Replies
    1. According to Cannings and Cannings (2006) only that species would be expected in Vancouver. The only other species known from British Columbia is Leptomantispa pulchella which is known from the Okanagan Valley

      Delete
  2. IMG_0579.mov I just found one of these unique bugs in northwestern Ontario near Minnesota border

    ReplyDelete
  3. My son found a Wasp Mantidfly on my kitchen window today. I'm in Ottawa, Ontario. Very interesting to watch and is bazaar to try and sort out if you've never seen or heard of one before.

    ReplyDelete
  4. We have found two in as many weeks, here in the Niagara Region in Ontario - don't recall seeing them before. Are they common?

    ReplyDelete
    Replies
    1. None of them are what I'd call "common" but in the right place you might get them regularly. Check out iNaturalist to see how many other reports of a given species there are and consider adding your observation there.

      Delete