because the red on this one was much brighter than any color on the numerous A. diadematus (what's the plural?) in the yard. They don't have red at all. And the eyes seem wrong; I can see only two in an upper row. The abdomen is an unusual shape, with indentations on the sides. Would that be a postpartum effect?

Two years running, A. diadematus hatchlings have appeared overnight in a nest web in the same place, built between one particular corner of a plastic dishpan that we use in the garden and the potting bench it rests on, and the web wasn't there the previous day. This year, it happened in February. So if this species lays eggs in November here, and if the mother guards the eggs, it's news to me.

The colors of the cross spider vary hugely. They range from every color between yellow to black, including reds and even dark purples. There is a very neat collage of them that I saw in an arachnology forum. I wanted to show you it but the web site is unavailable right now for some reason. I'll try again later. What identifies the species is the white cross on the back that is made of cells filled with guanine (hence the name Cross Spider). That cross, the epigynum with scape, and the eyes are what identifies this spider. You can only see two eyes in the posterior row because the focus is blurry where the other eyes are. The color of the carapace is a little darker there, too, making the lateral eyes hard to see in this particular specimen. The lateral eyes are really far to the left and right. See their eye pattern here:

Yes, the strange shape is a postpartum effect. The exoskeleton 'stretches' to the size of a marble while the eggs increase in volume in her ovaries. Once she deposits the eggs, the abdomen obviously needs to deflate since there's no volume there anymore...which creates a wrinkly, shriveled, lumpy abdomen. Imagine a 400 lb person who suddenly loses 300 lbs. There will for sure be lots of wrinkles and droopy areas. Here is a good demonstration of this effect:


And if you still have the spider around, check out her scape and epigynum and compare it to this one if you want to be sure about the ID:

The spiders hatched in April this year, not February. Here they are: In any event, April is pretty far from November. I wonder whether this species can produce two generations a year.

I don't want to manipulate a spider enough to photograph the epigynum, and my camera doesn't do well with such small structures anyway.

These spiders are a year-round species but are abundant in the fall. Quite often the females only mate once and will usually die at some point after the egg deposition. I'm not sure I'm understanding...are you saying that you don't think the SAME spider can produce two generations? Unless you've always witnessed the depositions, I don't think it's very safe to assume the same female laid the eggs.

It's not a big deal about getting an epigyne photo for BugGuide to use since there are already some in the guide...I just thought that you wanted to know the species (isn't that why you put it in Araneae?)...so if you want to indefinitely figure out the species, you need to look at the epigyne and see if it matches the photos I thumblinked to. You said something about using a jar to maneuver the spider for photos, so you can use the same technique to get the spider in the jar and then look thru the glass. Araneus diadematus epigynes are VERY easy to distinguish. The scape is quite big and you won't need any sort of 'viewing' contraption to be able to see it. But if you'd rather not look (or if the spider is gone), you might just have to take my word on it that it's a diadematus. Oh, and that site I mentioned last night is workling now. Kevin Pfeiffer included this link in the arachnologist's forum. You will be able to see a piece of the rainbow that is made by diadematus' (scroll down just a tad when you get there): Araneus diadematus collage

To clarify: No, I don't think one female would produce two sets of offspring in a year. My uncertainty concerns, among other things, the time of year when these spiders deposit eggs. The conventional story is that they mature in the fall, lay eggs, and die shortly thereafter. But I twice found new hatchlings in spring, and unless the eggs wintered over, the conventional story is wrong. If the eggs wintered over, the nest web where I found them should have shown up much earlier. The web appeared overnight.

Another source of puzzlement: you spoke of an egg sac and implied that the mother should have been guarding it. What we had this April and a year earlier weren't egg sacs. They were webs a few inches long. They would have been impossibe to guard like round egg sacs.

I found it interesting that a species would lay eggs in exactly the same spot two years running. Maybe a female returns to her birthplace, as salmon return to their spawning ground? I assumed it was a different female each time because A. diadematus doesn't live long enough for it to be the same one in two successive years.

I submitted photos because I'd never seen a spider that looked like this before, with the bright color and the unusual shape. The dorsal markings did look like that well-known cross, but the other features didn't match. I thought this must be a different species. I'll take your word on the ID. It's surprising, that's all.

Viewing the epigyne through glass would require a jar with a more uniform, nondistorting thickness of glass than I own. I also don't like to disturb animals more than I have to. See, I thought the strange abdomen might be enough for an ID.

Yes, you can find spiderlings of this species in Spring. That's actually the most common time to find them since they were deposited in the Fall and then, yes, overwintered in order to emerge in the Spring. Like I mentioned earlier, they are a year-round species, but often more commonly seen in the Fall when they are adults. You can find diadematus spiderlings at many different times of the year (I'm pretty sure), although Spring is truly the most common time to witness their emergence.

In order: April, May, June, July


Quote: "If the eggs wintered over, the nest web where I found them should have shown up much earlier. The web appeared overnight."

Hmm...I am getting lost in all of our comments. lol. Are you talking about the spiderlings that you submitted a photo of from April? If it really was a diademtus egg cocoon, and those spiderlings showed up in April, then the cocoon had to have been there, perhaps out of sight. Like under the lip of that Tupperware tub that they are dangling from. If you are sure, absolutely sure, that the cocoon wasn't under the rim or under the bench or...any other place...then I'm not sure what to say. I will say that the web they are on was made by the spiderlings themselves. It is likely more than one day old, as spiderlings stay huddled together (really close, like a ball) for sometimes up to a week (but usually less, depending on the air temperature) before they start to disperse from each other. In my opinion, that web looks like a few days work at least.

Quote: "Another source of puzzlement: you spoke of an egg sac and implied that the mother should have been guarding it. What we had this April and a year earlier weren't egg sacs. They were webs a few inches long. They would have been impossibe to guard like round egg sacs."

I'm not sure what you saw there. It's hard for me to imagine what you saw as 'webs a few inches long'. Have a photo by any chance? If the egg sac/cocoon doesn't look like these...



...then it's not a diadematus. Keep in mind that they will deposit their eggs on the underside of a leaf, or under the eave of a house, or...etc. There are many places. But they need a flat type surface because they don't make round, hanging type egg sacs...they are plastered to a flat surface, more like a cocoon I guess. The way the female makes them is really amazing! I've watched a few do it, plus I've read about it. She makes the 'roof' of the cocoon out of silk and then she craws under it! From there she makes the walls and such by turning round and round. It's really cool. And then she will wait, perched over the cocoon, and make sure it's safe and well-built...until she leaves to die (which won't be far off).

I don't think a diadematus female would return to the same spot it was 'born' in. Orb weavers are very opportunistic beings and they will live wherever they end up. After ballooning away as a spiderling, their entire future is in the hands of the wind. Wherever they land will become home. That is neat that you had spiderlings in the same spot two years running. There are SO many spiders and I think that it's an interesting coincidence...but if one spider can find a good spot to lay eggs, then of course another spider can do the same. There are other spiders that live longer lives and can mate more than once and lay multiple egg sacs...and they tend to stay in the same spot for a lifetime as long as they're never disturbed and forced to move.

I have to admit, I'm never quite sure if you are looking for answers to the questions that you pose, or if they are just rhetorical. I have horrible internet communication social skills. lol. So I apologize if I've become annoying.

And your spider is odd looking enough, I can understand why you'd be reluctant to call it a diadematus.

"Are you talking about the spiderlings that you submitted a photo of from April? If it really was a diademtus egg cocoon, and those spiderlings showed up in April, then the cocoon had to have been there, perhaps out of sight. Like under the lip of that Tupperware tub that they are dangling from."

Yes, that photo. It really was diadematus. Many of those spiders set up webs nearby. I got photos of them at various ages. The egg sac could have been under the lip. Now that I know the eggs overwinter, I bet that's where it was.

"I will say that the web they are on was made by the spiderlings themselves. It is likely more than one day old, as spiderlings stay huddled together (really close, like a ball) for sometimes up to a week (but usually less, depending on the air temperature) before they start to disperse from each other."

The web couldn't have been more than a day old. I see that area every day, usually using the tub for collecting dropped leaves, and I would have noticed earlier if the tub had been stuck to the bench.

The spiderlings may have stayed under the rim for the first few days. Once the web was there, they spread out during the day, and the crowd contracted in early evening when it got cooler. Each day, the spiderlings were bigger and fewer. They could walk away from the web. There may have been some cannibalism. Ants took some of them.

"It's hard for me to imagine what you saw as 'webs a few inches long'. Have a photo by any chance?"

Sure, the April photo. That web goes from the top of the tub to the corner of the bench, and not straight down, so it's a little longer than the height of the tub.

"And then she will wait, perched over the cocoon, and make sure it's safe and well-built...until she leaves to die (which won't be far off)."

So she guards it for a small fraction of the interval between deposition and hatching. I assumed the purpose of egg guarding was readiness to fight off egg predators. They might arrive in winter, too.

"I'm never quite sure if you are looking for answers to the questions that you pose, or if they are just rhetorical."

If I don't understand something, if it contradicts what I've read before, I'll ask. The questions aren't rhetorical.