Archive for the 'Arthropods' category

Where's Waldo - the invertebrate version

Jul 30 2011 Published by under Animals, Arthropods

I took a couple of pictures at the beach recently, of an extremely well-camouflaged invert. Can you see it in this first picture? (Clicking on any of the images will take you to flickr, where you can inspect the full size to your heart's content.)

Ocypode pallidula 1

Not sure what I was looking at yet? Let's zoom in a little.

Continue Reading »

One response so far

How many blue lobsters does it take to start a business?

Uncommon Descent, for some reason, just posted a link to an article about a blue lobster. This isn't the first time that a blue lobster has been found, and there are even rarer yellow and albino variants that are known. Since there is, as the UD article points out, a trade in blue crayfish, it's reasonable to assume that the blue coloration in lobsters is a heritable. All that leaves me wondering something: exactly why did the folks at Uncommon Descent decide to highlight this example?

The UD article contains the following gem:

Apparently, there is a trade in blue crayfish for aquariums, but any similar trade on blue lobsters depends on finding another one, of the opposite sex.

Does it really?

I didn't take a lot of time to research the genetic mechanisms underpinning lobster coloration (frankly, it's not a topic that fascinates me). I did find, however, that there's reason to suspect that the blue coloration is the result of a recessive trait (a paper I found noted that a prior study had found that blue offspring only occur when two blue lobsters mate). If that's the case, does a would-be purveyor of blue lobsters really need two blue lobsters to get the business off the ground?
Continue Reading »

18 responses so far

Friday Arthropod - a fly from Hawaii

Oct 05 2007 Published by under Animals, Arthropods, Biology, Picture Posts, Science

Last week, I had a picture of a live spider for you to identify. Most of the guesses came quickly, and were absolutely correct - the spider in the picture was a Spiny-Backed Orbweaver. This week's arthropod might be a little more challenging.

The picture below features a pinned museum specimen, and was taken through a light microscope at about 40x magnification. The edge of a quarter appears in the photo for scale. The species in question is unique to the island of Hawaii, and is found on the wetter slopes of the younger volcanoes.

Continue Reading »

4 responses so far

Friday Arthropod - Can You Identify This Spider?

Sep 28 2007 Published by under Animals, Arthropods, Picture Posts

A couple of weeks ago, I posted some pictures of some large spiders and asked for help in identifying one of them. Jerry Cates of Bugs In The News got back to me quite quickly, and identified the mystery spider as Nephila clavipes - the same species as the other ones shown in that post.

I took some more spider pictures this week. I've identified the species. Can you? The pictures are below the fold, along with some information about the size and where it was spotted. I'll post my identification on Monday.

Continue Reading »

10 responses so far

They Grow Them Big In Texas

Sep 11 2007 Published by under Animals, Arthropods, Biology, Picture Posts, Science

I was out walking yesterday morning when I saw several very large spiders sitting on webs. I had my camera with me, so I shot a bunch of pictures, and got a couple of really nice ones. I think I've managed to identify the species for a couple of the spiders, but there's one that I'm not quite sure of.

I'm pretty sure that three of the spiders are golden orb spiders (Nephila clavipes). The body shape is right, the markings are right, the site (League City, TX) is within the known range of the species, the habitat (marshy scrub along the bank of Clear Creek) is right, and the behavior (head down in the web) matches the descriptions I've read. The only thing that doesn't match is the size. According to the descriptions in the field guides I've looked at, the females typically have a body length of about 1". I was able to get a tape measure near enough the smallest of the three to get an estimate, and that one looked to be slightly over 2". The largest of the three was also the most distant - about 30' from my best vantage point - and it was hard to get a good estimate, but it looked to be at least 3".

The fourth spider looks a great deal like the other three, but there are just enough differences to make me wonder if it's the same species. There are some slight differences in the markings, and there seemed to be some differences in the web as well, although part of that might well have been due to the web being located in an area more easily disturbed by humans. The other spider was also a bit smaller than the others, but at a bit under 1.5" it would still be on the large side for N. clavipes.

Of course, I'm not a spider expert, so it's also possible that I've managed to misidentify every single one of these spiders. The best of the pictures are below the fold. I'm emailing the link to a couple of folks who might be able to help check my tentative IDs. The comments are, of course, open as always.

Continue Reading »

8 responses so far