Identification Challenge #9 Reveal

March 2nd, 2011 - 8:06 PM | Filed under Identification Challenges | 5 Comments

Kudos to all commenters on Identification Challenge #9. They all correctly determined that this was a closeup of an Onychophoran, commonly called a velvet worm.

January 18, 2011 | Gandoca-Manzanillo NWR, Limon Province, Costa Rica

These strange creatures have their own phylum, Onychophora, the name of which literally means “claw bearers”. You should be able to see those claws above, at the tips of their stubby little legs.

Wikipedia tells us there are only two surviving families, Peripatidae and Peripatopsidae, geographically separate. The range for Peripatidae includes Central America and tropical South America, making this a member of that family.

One of my main goals for this trip was to find one of these. I read up on them ahead of time, learning about where I might expect to find them. I succeeded on my second day, but sadly I only found this one.

Here’s a shot of how I found it, after turning over a small log.

Velvet worm, as found beneath a rotting log.

I’ll have more information and photos of this interesting critter in a separate post. For now though, check out its unusual hunting style in this brief clip from BBC’s Life in the Undergrowth.

Identification Challenge #9

February 27th, 2011 - 10:54 AM | Filed under Identification Challenges | 14 Comments

This challenge will be more like one of Ted MacRae’s Super Crop Challenges.

January 18, 2011 | Gandoca-Manzanillo NWR, Limon Province, Costa Rica

Can you figure out what this might be? Can anyone explain the relationship between what’s shown here and its name? You should be able to get to family here.

I’ll hold all comments in moderation for a while this time.

Identification Challenge #8 Reveal

February 5th, 2011 - 5:42 PM | Filed under Identification Challenges | 1 Comment

15mm | January 17, 2011 | Cahuita National Park, Limon Province, Costa Rica

I knew the photo above would be difficult to identify, but I was happy that everyone at least figured out it was a spider. As a side note, I hope everyone realizes you can click on the photo to see a larger version.

One commenter, biozcw, ventured that it might be an Argyrodes species. That’s close, because the species I believe I have here, Ariamnes attenuatus, was formerly placed in that genus.

This spider was hiding beneath a large leaf. At only 15mm as shown in the initial photograph, it’s small and virtually disappears when assuming that cryptic position. Here’s a decidedly more spider-like pose. You can just barely see a strand of silk stretching from the spinnerets towards the upper right corner of the image.

That looks more like a spider

The abdomen is somewhat bendable, as shown here. One has to wonder if that lighter colored abdominal tip isn’t perhaps wiggled to attract prey.

Showing bendable abdomen

Sara Rall ventured that it might be an ogre-faced spider (Deinopis sp.)? That’s a good guess, given the elongate body. What’s interesting is that this species might share the same prey capture strategy. As noted here, some Ariamnes species catch other spiders with a net.

I arrived at the identification by first determining it was an Ariamnes species and then checking the World Spider Catalog. There, I saw that A. attenuatus is the only species in Costa Rica.

Here’s a few more images.

Dorsolateral view

Another view

Finally, here’s a video of a different Ariamnes species.

Watching the spider, I’m even more inclined to imagine the tip of the abdomen being used as bait. You can see how the abdomen is long enough to actually bend over and dangle in front of the spider. Given that it may prey on other spiders, perhaps it’s used to teasingly pluck the thread’s of another spider’s web! Towards the end, the spider assumes a linear pose.

Too bad they don’t occur where I live. I’d love to keep one for awhile to see how it behaves.

Identification Challenge #8

February 3rd, 2011 - 7:07 PM | Filed under Identification Challenges | 9 Comments

15mm | January 17, 2011 | Cahuita National Park, Limon Province, Costa Rica

How specific can you get with an identification for what’s shown above?

Identification Challenge #7 Reveal

January 8th, 2011 - 1:31 PM | Filed under Identification Challenges | 2 Comments

All commenters correctly determined that this was a moth:

January 26, 2010 | Caraça Natural Park, Minas Gerais, Brazil

At the time I took the picture, I assumed this was a butterfly. It acted like a butterfly, being active during the day and the way it held its wings (not folded over the back like many moths).

It was only when reviewing the photo later that I noticed it looked a bit odd for a butterfly. Like many commenters, I noted the lack of clubbed antennae. I didn’t try to identify it, but I remembered it when I read an interesting short article in a recent issue of Natural History magazine. The article was all about day flying moths in the subfamily Dioptinae (family Notodontidae). I emailed the author, James S. Miller, asking if he thought this might be one. Here’s his response:

That moth is either a Geometrid in the subfamily Sterrhinae, or a Noctuid
in the subfamily Agaristinae. I wouldn’t be able to tell without looking
at its wing venations and tympanum. Sadly, not a dioptine. It looks
exactly like several species in the dioptine genus Erbessa however, so you
were not far off. Mimicry in these taxa is phenomenal.

Thanks to Mr. Miller for responding.

Identification Challenge #7

January 5th, 2011 - 8:24 PM | Filed under Identification Challenges | 8 Comments

January 26, 2010 | Caraça Natural Park, Minas Gerais, Brazil

This challenge will be straightforward. Is this a butterfly or a moth? Why?

Here’s a habitat shot, showing the shot above was taken during the day. The subject above is the yellow speck near the bottom, center right.

Subject above is just barely visible here

Identification Challenge #6 Reveal

December 11th, 2010 - 2:17 PM | Filed under Identification Challenges | No comments

As I suspected, this challenge was easily met by all commenters.

October 8, 2009 | Twelvestones, Roswell, GA, USA

It is of course Arilus cristatus, commonly known as the wheel bug for the very structure shown above. I didn’t get a full body shot of this specimen, but here’s a wider view.

Facing opposite direction from the previous image

Among the largest assassin bugs in North America, they can deliver a painful stab with that beak. I foolishly held one when I was a kid, and I’ll not be making that mistake twice.

For more info, see the species info page at BugGuide.

Identification Challenge #6

December 7th, 2010 - 5:50 PM | Filed under Identification Challenges | 3 Comments

Now that Alex Wild has posted about my identification challenges (among others), I feel obligated to do another one.

October 8, 2009 | Twelvestones, Roswell, GA, USA

Here’s a closeup of a rather distinctive part of an easily recognized critter. Can you name it?

Identification Challenge #5 Reveal

November 28th, 2010 - 8:43 AM | Filed under Identification Challenges | No comments

As usual, Ted C. MacRae was right on all counts for this challenge:

January 28, 2010 | Caraça Natural Park, Minas Gerais, Brazil

I thought perhaps the swept-back antenna across the bottom third of the photo might throw people off. Not so.

Here’s a better shot of the katydid which was cooperative enough to allow some good closeups. This should put all the body parts shown above in context.

Katydid

My sister guessed a dragonfly via a Facebook comment. I can see the resemblance so not a bad guess.

Identification Challenge #5

November 21st, 2010 - 8:27 AM | Filed under Identification Challenges | 2 Comments

January 28, 2010 | Caraça Natural Park, Minas Gerais, Brazil

Here’s a closeup of an unidentified insect. Can you identify the family to which it belongs and the body parts shown?