Lynette,

Thanks for the very useful tip! This, only with two other Zygiella species, is now Parazygiella. And I realize now that the best-match ventral drawing from Levy that I was looking at, which is indeed a better match than that of Z. x-notata, is from this species. Levy describes the distribution as including "a few records ... from the coast of California [Pacific Grove - Gertsch, 1964]" and the female holotype comes from Monterey Co.

I downloaded Gertsch, 1964, and the very first thing that caught my eye was: "Zygiella carpenteri of the far western United States seems to spin only complete orbwebs, but reinvestigation of this conclusion is desirable".

Hmmm, a few things are beginning to come together. Looking at Gertsch's distribution map for P. carpenteri, I see one flag on the central CA coast and several that I would describe as being in "inland northern California" -- Alameda County is more or less between these two regions.

Gertsch's description doesn't entirely fit our specimen here -- he describes the legs as being "quite uniform in color, without distinct darker marking except on femora where indistinct dusky rings or spots are present". With respect to habitat, he writes: "This interesting species lives in cracks on rock walls and especially on the trunks of yellow pines and other large coniferous trees of the California Sierras." Therefore more information about where the specimen was found might be helpful.

So, this is a specimen that would be worth collecting and examining more closely.

-K

what's the difference between the webs or P. carpenteri, P. dispar, and Z. x-notata?

this opens up a whole new can-o-wormies. We'll have to do some moving...

Sector or not I would tend to agree. The ventral aspect as well as the
shape of the abdomen (oval, widest in the middle and dorsoventrally flattened [Levy, 1974]) and the folium all say Zygiella.

-K

She stayed in the center of the web, and it wasn't particularly near water. I don't think the web was missing any sectors.

One observation: when I approached, the plane of the spider's body was at an angle to the plane of the web, maybe 25 or 30 degrees, not flat on, as they usually are.

Today I reexamined the web. It was about half collapsed, but enough of it remained to show its original structure, and I'll be darned if there weren't two adjacent sectors without cross threads. These were at the top of the web. I followed the spoke between them to its upper end and found the spider hiding near the end of a twig. Yes, the tree is a small conifer. I'll add a photo.

Yesterday, though, she really did occupy the center of the web.

Today the spider had a new web. One sector, with an angle of about 30 degrees, was mostly missing. Three threads crossed this sector in random directions, all in its lowest third (i.e., the third nearest the hub), as if the spider had some idea of missing-sector webs but hadn't quite got with the program.

The web is attached to the tree at many points. I counted 16, and there may be others. It measures about 13 inches from the highest anchor point to the lowest. The multiple anchor points and strands between them make this web, exclusive of the central orb, somewhat three-dimensional, there being about 2 inches between the front and the back.

Above the web proper, near the spider's hiding place, is an auxiliary structure containing dead prey. I don't know whether this is a pantry or a trash heap. It's about an inch in diameter, with a chaotic shape, and is made of coarse white silk, easier to see than the web proper.

At least three other spiders of the same kind have webs on this tree. I made further observations of their webs and photographed the auxiliary, chaotic structure of one of them. Where should I post these? They don't show the same specimen.

These webs are on the north, northeast, and east sides of the tree, where foliage is less dense than on the sunny side. The more widely spaced branches on the shady side allow space for large webs.

Is anyone else subscribing to this node? I can write up my notes about these variable webs and observations on behavior when I know where to post the material.

A Web search didn't turn up much about this genus. I didn't find pictures of carpenteri. It seems that lifestyle descriptions for Parazygiella are scarce. This seems odd because these spiders must be common if there are four of them in a six-foot tree in my yard.

Dear G.,

It was Wunderlich (a one-man publishing house in Germany) who reassigned these to a new genus in 2004, I believe; previously it was known as Zygiella carpenteri. Perhaps that will help with your search. But it is not unusual not to find images of Nearctic species. Except for a few common species that are readily identified by appearance, most spiders require a genital inspection and even then can be sometimes rather difficult to identify. So, if any images at all are to be found, it's not uncommon to see only "Zygiella sp.".

The Holarctic species are better represented; that is perhaps because Europe is a much smaller, but more densely settled region. In Germany I think we have perhaps 1,000 species of spiders (as opposed to how many in N.A.? 3,000+?) Germany also seems to have a more active (relative to size) group of "intermediates" -- non-professionals with a serious interest in spiders, and this is the group, I think, that is most interested in disseminating easily accessible information (including images) about the various species.

Finally, if you are interested in writing a BG article and recording extensive notes (both a good thing) that are to be taken seriously, I can only encourage you to sign your real name. (Imagine the citation: "in his/her notes on the species, 'G. Whiz' reports that...") It also wouldn't hurt to collect one or two of these specimens (male and female is always helpful) so that you can be sure about your species -- otherwise such notes have much less relevance.

[Sorry, John I see now I've repeated some of your advice.]

-K.

No question, "G Whiz" would not be taken seriously as a source. However, I use the same screen name here as on a discussion forum that includes heated arguments over religious questions. The forum attracts its share of nutcases. I'd rather not have my real name findable from there. At a forum on another subject, I'm an administrator, and we get our share of nutcases, too. My screen name on that forum is different, but information there might lead a skilled searcher here. Because of something that happened a few years ago, my name and my city are connected on the Web. There is such a thing as Web stalking. I'm being cautious.

I like your meticulous observations.

The post I'm replying to was much longer. On the page for replying, however, it says only "I like your meticulous observations." You must have edited it, or else there's a tech glitch.

The purpose of reporting more is to add information. Identifying the species would certainly be one goal. Maybe enough is known about how webs and behavior differ in this genus that details would place these specimens in a species--just not known at this moment by the few who have visited this page so far. Spider scholars, I suppose, have many books and monographs, and the facts might be around somewhere.

Then, there seems to be an information gap generally about this kind of spider. I can't find much from Google. I might be able to add to the knowledge base. (I might not, too. Not everything is on the Web.)

As your phantom comment pointed out, I can't add to a species page that doesn't exist. If I could add to the present page, though, the additions could be moved to a species page when one is created. But comments are supposed to pertain only to the specimen in the photo. My problem is, I have notes about this specimen and others nearby. In fact, one of the observations is that the webs differ in shape although all these spiders look alike and are presumably the same species--an observation that intrinsically requires multiple specimens.

Let me put it differently. Is it permitted to use a page to report observations about other individuals than the one in the photo on that page?

> The post I'm replying to was much longer

My fault. I went to add to my comments and accidentally lost them in the process! Let me try again.

First, the life cycles and habits of most spiders just haven't been studied all that closely. No matter what has been written about these spiders, I'm sure there is still much to learn about them. So, your observations are important, even if they confirm what has already been noted. Science is partly about identifying trends, so if you can confirm what someone else has already noted that's very important.

If you plan to make a study of these spiders, beyond a casual interest, then try and locate and read every peer-reviewed paper about them that you can find, so you'll know what is or isn't known to this point. For many spiders that turns out to be surprisngly little! There aren't that many arachnologists out there writing papers on the life cycles and habits of spiders - because, there just aren't that many arachnologists to begin with. With many thousands of species, not many have been studied in detail to date, as far as I know.

In your search for information, have you looked under Zygiella dispar and Z. carpenteri? Until just recently both spiders were in that genus. The older papers will use that name.

If your notes are to add to what we know about these spiders, then it is essential that you collect the individuals you've been observing and get them identified to species by an expert. Without that the notes will have little scientific value, because no one will know just what spiders they refer to. Also, you'll need to keep the identified spiders as "voucher specimens" to back up your notes. This is especially important if you ever wish to publish them.

You say there are several different spiders you've been watching. If your hypothesis is that webs differ between different individuals of the same species, then before you can test this you absolutely must be able to say whether the spiders are, in fact, the same species. Make sure you collect the exact individual spiders referred to in your notes and have them identified.

> Is it permitted to use a page to report observations about other individuals than the one in the photo on that page?

I don't know what's permitted in BugGuide, but if you have identified a number of spiders as the same species then I'd say it's okay to write notes about them on the same page. The key is a positive identification of the spiders as being the same species. Perhaps the writeup of your notes (Lynette suggested an article) could go on the species info page, rather than the species image page?

Hope this helps. :)

I did search for images under both genus names. None of the images matched these specimens. For example, the white dorsal markings on P. dispar are too big and too rounded. P. montana (on a European site) has an almost circular abdomen in dorsal view and not enough black in the markings. No images for carpenteri with either genus name.

I haven't the training or the resources to produce a professional-quality report of the kind you suggest. Lack of access to reference materials is one obstacle. I'd also need a crash course in terminology. As just one example, there may already be a name for the small supplementary web that contains dead prey. If there is, describing the thing instead of using the accepted word would look bad and keep the report from being taken seriously, even if I were to throw privacy concerns aside and use my real name. I also prefer not to kill the spiders, which I'm afraid is entailed in the word "collect."

Of course the species would have to be identified. But all these specimens look alike. Bugguide old-timers identified my Enoplognatha ovata from its appearance without harming the specimen. Can't the current specimen be identified the same way? Perhaps it's P. carpenteri, but no one seems to have a picture. Since P. carpenteri has a species name, someone somewhere must know what it looks like.

If a photo of a female P. carpenteri is found and the current specimen matches it, would that be good enough for an ID? If the current specimen doesn't match the photo, then what? Would the observations about webs and habits go on the genus page, with an explicit reservation that the specimens appear to be one species but this hasn't been verified?

If your hypothesis is that webs differ between different individuals of the same species, then before you can test this you absolutely must be able to say whether the spiders are, in fact, the same species.

Well, that isn't exactly a hypothesis at this point. It's more like a finding. The same specimen had two varieties of web on successive days. If one individual's web can vary when she rebuilds it, then the webs in this species, whatever it is, can vary.

> If a photo of a female P. carpenteri is found and the current specimen matches it, would that be good enough for an ID?

I wouldn't say so. Some spiders can appear to match each other and not even be the same genus:



A lot of different spider species look very much alike. So, generally, comparing your spiders with photos of other spiders is not the most reliable way to identify a spider to species. With only a few exceptions, you should consider any ID of a spider that was made by comparing it to pictures of other spiders as "tentative," but not definite - especially if that ID was made by non-experts. Rod Crawford has a written a good overview of how to properly ID spiders. It's tougher than you might think:

http://www.washington.edu/burkemuseum/spidermyth/myths/easy.html#markings

> Well, that isn't exactly a hypothesis at this point. It's more like a finding. The same specimen had two varieties of web on successive days. If one individual's web can vary when she rebuilds it, then the webs in this species, whatever it is, can vary.

That's different from what you said in your previous post. I was refering to these comments:

> My problem is, I have notes about this specimen and others nearby. [your emphasis] In fact, one of the observations is that the webs differ in shape although all these spiders look alike and are presumably the same species--an observation that intrinsically requires multiple specimens.

Okay, I'll try to construe IDs from photos as tentative no matter how confident they sound. These specimens may not even be Parazygiella.

That's different from what you said in your previous post. I was refering to these comments:

> My problem is, I have notes about this specimen and others nearby.

The information about Specimen 1's two webs was spread out over two posts. That Specimen 1 made two designs shows that webs in this species do vary. Descriptions of the other specimens' webs would show that they vary more, assuming that these are conspecifics. Just wait till you get to Specimen 4!

In what I've said about webs, I was addressing this quotation: "Zygiella carpenteri of the far western United States seems to spin only complete orbwebs, but reinvestigation of this conclusion is desirable." If I've got carpenteri, then here's some reinvestigation from the far West. None of these webs were complete orbs. One or two sectors were all or partly missing.

The only thing that remains to be done is a positive ID of these spiders. You mentioned not wanting to kill the spiders, and maybe you can get around that. An arachnologist (probably at a university or museum) who is familiar with these spiders might be able to recognize them on sight. I'm sorry I don't know who to recommend from your area (maybe someone reading this knows who to contact), but if you took some of the spiders to them then perhaps you could get an ID and then later release the spiders back where you found them, unharmed. You won't have voucher specimens in that case, but since your studies are of a more casual nature you probably won't need them. Saying the spiders were identified for you by such and such arachnologist would be good enough for an article in BugGuide.

Hope this helps, and I look forward to reading your findings once you get them together in an article. :)

Pictures of the different webs and structures would be great for this, BTW.

I have photos of at least one of the prey-storage webs. I tried misting one of the main webs, and it still didn't photograph "legibly."

Does anyone know of an arachnologist at the California Academy of Sciences who could get a start on an ID from photos? Then our membership dues would indeed be money well spent, and I might not have to figure out how to capture and transport these elusive spiders.

Try Darrell Ubick: dubick@calacademy.org (that email address is in the public domain, so I think it's okay to post it here).

There are some other spider people at the Academy as well, I think.

Let us know what you find out!

for that lead. Probably okay to post the address, but inserting extra characters to disguise it from spambots would be a good idea.

I e-mailed:

> > Subject: Help with orb weaver ID?
> >
> > Dr. Ubick,
> >
> > Your name was mentioned at bugguide.net as someone who might be able to
> > help identify a spider. Several individuals are living in a tree in my
> > yard in [city]. At bugguide, we think they're /Parazygiella /sp. They
> > might be /P. carpenteri, /and no one there has a picture of that
> > species. /P. carpenteri /is recorded in California, although not
> > specifically in the Bay Area. My specimens spin missing-sector webs,
> > but
> > not perfect ones. Their webs vary quite a lot, even webs made by the
> > same specimen.
> >
> > Dorsal and ventral photos and the discussion are here:
> >
> > http://bugguide.net/node/view/297726
> >
> > (On that site, I'm "G Whiz.")
> >
> > Thank you for any help.
> >
> > Regards,
> > [name] (Ms.)

He replied:

Hi,

You may be correct about it being P. carpenteri. Unfortunately, I would need to examine specimens to be sure. If you send me a pair of specimens, a male and female, I'll get them id'd.

Cheers,

Darrell Ubick
Department of Entomology
California Academy of Sciences
[etc.--address]
_______________

It's back to square one. How would I even find a male, let alone know it was the same species as these females?

Males of orb weaver species can sometimes be found at the outer edge of the female's web. That's the first place I'd look. The males come to the females, so go to the females to look for the males.

Is this seasonal? That is, when would I look? I check those webs often and haven't seen males near them, except a male of a smaller species (I guess) who was walking on the outside of a different kind of web, not an orb. By the time I returned with the camera, the female whose web it was had killed him.

Some of these specimens have now enclosed themselves in small webby "rooms" around the top of the signal line. Would Parazygiella be the kind to die in its nest when cold weather comes? Then I could collect the females easily and humanely.

If you choose not to take Lynette's suggestion of writing an article to post in the forums, then I would recommend that you post each individual spider (or web) as a separate post and then link them together using thumbnails. For examples of what I mean, please see my post of these stiletto flies which I presumed were all the same species. As another example, see Ron H.'s post where he links several posts of different species together to form an overview of a small insect community he observed. For technical help on how to include thumbnail links, see the last item on this page.

This looks like a practical way, thanks, only I don't yet know what species to call it or even what genus, really.

The posts by yourself and Ron make great examples (and good reading!).

I think an article would be a good place to compile this information.

but I'm not sure what to do with the information yet.