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Cicindelid higher classification

Another consequence of the recent Treatise of Western Hemisphere Tiger Beetles (Erwin and Pearson 2008) was a change in the group's higher classification. I made brief reference to this in my previous topic discussing the book's subgeneric elevations without giving more detail. With regards to the North American fauna, the new classification is as follows:
  • Family Carabidae
    • Subfamily Carabinae
      • Supertribe Cicindelitae
        • Tribe Cicindelini
          • Subtribe Megacephalina
            • Genus Amblycheila
            • Genus Omus
            • Genus Tetracha
          • Subtribe Cicindelina
            • Genus Brasiella
            • Genus Cicindela
            • Genus Cylindera
            • Genus Dromochorus
            • Genus Ellipsoptera
            • Genus Eunota
            • Genus Habroscelimorpha
            • Genus Microthylax
            • Genus Opilidia
The main impacts from this new classification (aside from the now addressed subgeneric elevations) are:
  1. The genera Amblycheila, Omus, and Tetracha are now all placed within a single tribal-group taxon (currently the first two genera are placed in the tribe Omini, while the last is place in the Megacephalini).
  2. The tribes Megacephalini and Cicindelini are reduced to subtribes within an expanded tribe Cicindelini.
  3. Tiger beetles as a whole are considered a supertribe within the subfamily Carabinae rather than a subfamily within the Carabidae.
As far as I can tell, combining the three genera formerly included in the tribes Omini and Megacephalini into a single higher taxon is relatively easy. However, reducing the tribes to subtribes and the subfamily to supertribe seems to present a challenge in terms of the current BugGuide structure. I therefore propose a blended approach in which we combine the Omini and Megacephalini into a single taxon but maintain it at the tribal level (Tribe Megacephalini). Likewise, tribe Cicindelini and subfamily Cicindelinae would also be maintained at their current ranks. Thus, the BugGuide higher classification would be:
  • Family Carabidae
    • Subfamily Cicindelinae
      • Tribe Megacephalini (includes Amblycheila, Omus, and Tetracha)
      • Tribe Cicindelini (includes Cicindela and its former subgenera)
My main goal here is to make the higher classification reflective of current opinion without unnecessarily complicating the taxon heirarchy with seldom-used secondary ranks. All points of view on whether my proposal accomplishes that are welcome.

infraspecific taxa
please see discussion here
to avoid perpetuating the problem, i suggest that the tiger beetle experts start a thread to discuss the matter on this forum and take action to make sure that forms without well-established taxonomic status are not treated as taxa in the guide. those numerous subspecies pages we have now are misleading, and at the very least some language explaining the current situation must be added to every such page, although i personally wouldn't be satisfied with that solution.

 
Having BugGuide follow *current* published nomenclature
has always been our policy I thought, regardless of how much work now or future undoing this might entail. Why should the policy be any different for the tiger beetles? Simply don't specify subspecies level when a particular specimen shows sufficient hybrid featues, but certainly preserve subspecies names for the classic ones morphologically & geographically. The "current" most comprehensive authoritative references which BugGuide needs to follow are the familar Field Guide by Pearson et al. (2006), Nomina Carabidarum by Lorenz (2005), and the Treatise of Western Hemisphere Caraboidea II by Erwin & Pearson (2008). I don't believe there is any significant disagreement among these three works. My approach is stubbornly simplistic and it works! Forget about the so-called "DNA approach" which can fly in the face of obvious and constant morphological differences.

 
What about the ICZN?
Peter,
I agree with what you are saying. It also must be remembered that regardless if one agrees with the use of the trinominal system or not, the ICZN recognizes them. My request is for consistency, currently, bugguide has pages for some tiger beetle subspecies, so it seems to me that you're all in or all out.

A more important issue I see on Bugguide is people trying to put subspecific names, and sometimes specific names based on photos.

In the case of images I uploaded yesterday, and which brought me to this discussion, is my request for subspecific pages.
Here is the thread
http://bugguide.net/node/view/630934

I am the author/co-author of some of subspecies I uploaded yesterday, so I have a sense of what I'm doing.

Thanks
Mike

 
I have nothing more to say and
I'm getting confused by the different threads on these matters. Hopefully one of our experienced editors with plenty of free time and passion for tiger beetles will come forth to create the needed subspecies pages. Then we can all move on.

 
I've chewed over this for awhile...
...and can't escape the feeling I've had all along that BugGuide should strive to reflect the current state of taxonomy in any given group as best it can without attempting to judge the merits of a particular classification (i.e., assuming the goal of BG is to be informative in such a manner - others may have different opinions about the purpose of BG, easy ID being the most frequently voiced one, although I still fail to see how multiple goals are necessarily incompatible).

As a result (and regardless of my own personal feelings about the validity of this or that subspecies), if it is a currently recognized taxon then I see nothing wrong with creating a subspecies page for it. Some here have made blanket statements that the current trend in taxonomy is to subsume historical subspecies. This may or may not be the case depending on the taxon, but there are enough examples of subspecies being elevated to species status as more detailed information becomes available about behavioral/ecological differences despite only subtle differences in outward appearance. Charismatic examples include Cicindela albissima (formerly a subspecies of C. limbata), C. scabrosa (formerly a subspecies of C. abdominalis), and the recently rediscovered and soon to be elevated C. floridana (formerly a synonym of C. scabrosa). The trend is entirely opposite in Buprestidae, most of whose former 'host-based' subspecies have been elevated to species rank in recent years - these species are difficult to separate by morphology alone but are nevertheless reproductively isolated due to the high fidelity they show regarding preferred host plants.

It is much easier to sink records of a subspecies into a species if the former is later deemed invalid than to tease apart pooled records for a subspecies that is later deemed worthy of species status.

 
thanks a lot for this well-reasoned opinion
definitely a good food for thought.
the "current state of taxonomy" may also be subject to interpretation (i'm thinking how exactly this test would work if applied, say, to Podabrini [Cantharidae]... but that's a topic for a separate thread.)

A question
In your post on subgeneric elevations, you said:

"On the other hand, it should be noted that Erwin and Pearson's treatment of the entire group as a supertribe of the subfamily Carabinae rather than according it subfamilial status is not only more contentious. . ."

Can you elaborate? Is this a less widely accepted change than are the subgeneric elevations? And if we go ahead with this change, are there other supertribes that should be created within Carabinae?

 
The debate...
...centers not on whether the cicindelines are a subgroup of carabids - recent molecular evidence is making that clear, but rather how deeply it is embedded within that clade. I don't consider myself anything more than a reasonably versed amateur regarding molecular phylogenetics, but my general impression of the molecular data is that they indicate a very recent divergence of cicindelines from carabids. Carabidologists appear to be more objective in assigning whatever ranks fits the molecular data, while cicindelologists - especially in North America - are often inclined to argue for the highest level of distinction. Terry Erwin is a carabid specialist, thus his placement of the group as a supertribe within the Carabinae is in line with the molecular data. Ron Huber and other cicindelologists will argue that the tiger beetles are just too distinctive to be sunk to that level, but I think it is a case where passion is clouding objectivity - the molecular data really have been quite convincing (it was probably only a year ago that I was still arguing for family status!).

Erwin's word is not the last or only word on ranking. But, for now, it is the word in terms of New World classification. That alone makes it a good standard for BG to follow, as adherence to recent, comprehensive classifications is, I think, the most objective and efficient way for BG to stay current. I don't think it benefits BG and its user community to dismiss the peer-reviewed, published views of recognized experts just because a user of this site personally disagrees with those published views. Inasmuch as BG can accomodate recent classifications, we should do it (my statement that you quote was made when I thought BG did not provide the structure for supertribal classification - in which case I felt it was better to stick with the conventional classification, since BG could accomodate that classification). Since BG does provide a structure for utilizing all possible ranks in a higher classification, I favor taking advantage of them whenever possible.

I don't know carabid higher classification well enough to answer your last question, but Erwin's work is one part of a multi-volume set treating the entire family. I would suggest it could be the basis for BG's classification of the family as a whole.

 
Carabidae
I'm curious what the most recent phylogenetic papers are for the Carabidae. I've read Maddison et al.'s (1999) paper using 18S, which suggested cicindelines were closer to harpalines, but had difficulties resolving their true position due to long branch attraction. Have there been more recent papers you can recommend that suggest a placement within the Carabinae?

 
The recent paper...
...by Beutel et al. 2008 presented a genus-level phylogeny for Adephaga based on multiple cladistic analyses of morphological and molecular data. Cicindelinae were recovered as a monophyletic clade within the Carabidae but were not placed within any of the traditional carabid subfamilies. However, they admit that resolution of the carabid portion of the tree was very low, with some relationships suggested by the branching pattern appearing very unlikely.

I wish I could say more about the higher classification that Erwin has adopted for the Carabidae as a whole, but I don't have volume 1 of his Western Hemisphere treatise. For what it's worth, the Carabidae page of Tree of Life website is also listing tiger beetles as the supertribe Cicindelitae, and I suspect the rest of their arrangment is following Erwin.

 
Carabidae
Thanks, Ted. I don't have any strong feelings on the matter, but I think it may be prudent to leave the classification as is until you or someone else figures out what Erwin's complete classification of the family is. From what I've seen so far it looks like things are pretty unstable right now and more work is needed to resolve the phylogeny.

 
As I mentioned above...
...it appears the Tree of Life website has adopted Erwin's classification for the family. Nevertheless, I didn't propose an overhaul of carabid higher classification, just tiger beetles (for which I have figured out Erwin's classification).

From a more general perspective, are you really suggesting that we should ignore classifications (especially comprehensive treatises such as Erwin's) unless we feel assured they will never change? The only groups in which classifications don't change are groups that nobody is studying. Active study brings refinements as new knowledge is gained, and the more popular a group is the more frequently its classification will be refined. It seems nonsensical to me to arbitrarily 'freeze' classification schemes in popular, actively studied groups.

 
Phylogeny
That's not at all what I suggested. However, your suggestion as I read it seems to address only part of the revised classification and could conflict with whatever we're following for the rest of the carabids. If we move cincindelines into a supertribe in the Carabinae without understanding the rest of Irwin's classification we may be confusing things unnecessarily. What other groups does he place in the Carabinae? What would the other supertribes be? Tree of Life doesn't help here, as they have Cicindelitae sitting in a massive unresolved polytomy below Carabidae. I suppose we could follow their classification and move various tribes and supertribes to sit below the family - I would be more in favour of this move as we would at least know how to move things in the entire family.

The lack of information on what data supports Erwin's classification also gives me pause. If we were following a phylogenetic paper that presented solid data, came up with a phylogeny, and proposed a classification based on that phylogeny I would have no objection. Here we seem to operating in the dark to some extent. However, as I said I don't have strong feelings as this isn't my group, so if you and the other beetle experts come to a consensus on following Erwin, go ahead.

On the larger issue of classification, I don't think it necessarily benefits Bugguide to slavishly follow the latest classification, especially if we know it's going to be controversial. In my view, this site isn't focussed on phylogenetics, and there are many areas where our classification is completely unphylogenetic in the interest of easy navigation - see the higher classification of Hymenoptera (paraphyletic Apocrita, paraphyletic non-bee "Apoidea") and Diptera (4 of the 5 "No Taxon" groups below the order are paraphyletic). I know this is controversial with some contributors, so if you have an issue with this it may be something to bring up in a separate thread and try to achieve consensus.

(I should note that my earlier comment was only on moving Cicindelitae under Carabinae. Getting rid of Omini is a pretty minor change, and that isn't what I was objecting to).

 
I don't understand...
...how changing the category of tiger beetles from subfamily under Carabidae to supertribe under Carabinae causes confusion in the rest of the carabids. I also don't understand how this makes tiger beetles harder to find or navigate - typing "tiger beetle" in the search box brings up a bazillion images and guides that drill down through the entire classification to species level. The whole results page can be scanned in a matter of seconds, and the user is free to select any taxon at any level for a closer look. Nothing about this proposal breaks them up into disparate groups (monophyly of tiger beetles is rather universally accepted), and in fact, the opposite occurs with everything going into one tribe with two subtribes rather than the current three tribes.

There is and always will be a diversity of opinion here about whether to follow current classifications. The debate re-emerges every time anyone proposes any change to any higher classification, and the more popular the group, the more vociferous is the opposition. It is unlikely that we will ever acheive consensus on that core issue regardless of how much we banter it about, but to characterize as "slavish" the desires of those who do want current classifications is a trivialization and not reflective of the value of their contributions to BG. Until BG comes out with a "white paper" policy, the impacts will have to be considered on a case-by-case basis, and in this particular case, the risks to easy navigation seem rather non-existent.

Frankly, I'm losing the motivation to worry about it anymore. Writing papers and navigating peer review seem to be more productive (and easier) uses of my time.

 
Sorry
Some of my comments weren't as clear as they should have been. I didn't mean that this change in particular would make navigation more difficult, or that this was an example of slavishly following the latest classification; I just think those are things we should be cautious of in general. I hope my comments here don't deter you from continuing to try to improve the classification in Bugguide, because there certainly are many areas that could be improved.

In this case following Erwin's classification is easily justified as it is the basis for the definitive treatment of the fauna; my primary objection is that it makes little sense to move a single clade when the classification involves more extensive changes. A subfamily Carabinae containing the three tribes currently in there and the supertribe Cicindelitae would have rather different implications for the relationships of the tiger beetles than one containing Carabitae, Cicindelitae, Nebriitae, and Omophronitae, as seems the classification on the INBIO page I linked. If you don't have the interest to redo the entire Carabidae, would a suitable compromise be to adopt this 4 supertribe classification within the Carabinae and leave the rest of the family as is for now?

 
Phylogeny
After writing the above I googled "Erwin classification Carabidae" and came up with this page from INBIO. It's restricted to the Costa Rican fauna, but it does have Cincindelitae under Carabidae, along with Carabitae, Nebriitae, and Omophronitae. I assume this is Erwin's classification (although Google only found it because he's the author of some of the included genera). Any thoughts on following this classification (assuming it includes enough of the Nearctic groups to be usable)?

Modifying higher taxonomy
Changing the structure so that it perfectly matches Erwin and Pearson would be pretty straightforward. We would just use the "no taxon" rank to create the supertribe and subtribes, as we do for ranks such as subgenus (e.g. here). I would hope that when BugGuide 2.0 comes around we will be able to give such ranks their proper names. The "no taxon" rank also gives us the option of omitting the names of ranks if they are still being worked out, as is done with the parasitic lice here.

I'm not well-informed enough to have an opinion on your proposal at this point, but I would say that we shouldn't let BugGuide's structure affect the ranks we assign if there is consensus among specialists for a certain scheme.

 
Actually...
BugGuide has those categories. If you do "add guide" under a Subfamily-level node, the pop-up menu may default to genus, but includes:

No Taxon
Supertribe
Tribe
Subtribe
Infratribe
Genus

I know, because I just tried it (as long as you don't click "add", it won't hurt anything).

 
How 'bout that...
I wonder why we have those and not subgenus, which is a much more commonly used rank than supertribe/subtribe/infratribe?

 
That's a good question...
...and one that hopefully BG2 will address.

 
Very cool...
By all means, then, we should utilize them.

 
Apparently...
...BG has more functionality than I realized. That being the case, I am all for aligning the BG higher classification with Erwin and Pearson.

I think one huge functionality that people forget about is the "view all" link at the bottom of the taxon heirarchy that allows one to see all nested taxa on a single page. Such functionality would seem to negate the argument by some that "excessive splitting" of taxa makes their subordinate taxa difficult to find.

 
All or nothing
With speciose groups like beetles, the problem is that "view all" shows you all the subordinate taxa, which can run to pages and pages. It would be nice if one could control the number of levels (it's been suggested), but that's the way it is for now.

 
Every search option...
...has its advantages and disadvantages. I mention this one here because it would seem to be a good option for this particular taxon. In other, more speciose groups, one of the many alternative methods may be better. Your suggestion to have some control over the number of levels would be nice.

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