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Hello,

I hope this question does not prompt such a "heated" discussion as the one concerning screen lids and total heat (are these forums moderated?). So, without much more delay, can anyone tell me the taxonomic status of V. albigularis? It seems to me that most people (at least private breeders and hobbyists) disagree on the issue, but my question focuses on the official status of the "complex" among the respective authorities of nomenclature. What is the most current study involving this question, and what are the methods used to answer it (morphology, squamation, phylogenetics, coloration)?

I look forward to hearing from you, and I thank you all in advance.

Kind regards,

Fabian

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Fabián Aguirre
Zookeeper/ Freshwater Aquarist
Department of Herpetology and Freshwater Biology
The Dallas World Aquarium
(214) 720-2224
fabian@dwazoo.com
www.dwazoo.com

Hi Fabian,

According the most recent publication: Varanoid Lizards of the World (Edited) By Eric Painka, Dennis King and Ruth King, the chapter on V. albigularis written by Andy Phillips states there are three subspecies: V. albigularis albigularis, V.a. microstictus and V.a. angolensis. He does not say why V.a. ionidesi was omitted, or provides data on the aforementioned systematics....in 2000, I and Robert Sprackland wrote a 2-part article in June-July Reptiles magazine on how all 'races' (= subspecies) were the same with respect to osteological morphometrics (= skull shape/structure) regardless where they come from across Africa (Eygypt to Cape Town). We therefore said all forms of V. albigularis were 1 species with variations on the theme - Andy either over-looked this, as well as my distribution papers (J. of Ecology 1997, 37:354-357; J. of Biogeography 2002, 29:1643-1701) which provided a detailed distribution of the afore-mentioned V. albigularis types - and other African types as well. I am working on a formal academic treatise of this now....and it is very technical and full of old/new data...so according to academics = a complex group consisting of 3 subspecies, related to V. exanthematicus and V. niloticus, with V. yemenesis its closest relative, also found on African Continent in Djibouti. According to me it is a monotypic group, consisting of 1 species.

There are the 'clumpers' and 'splitters' in studies of evolution, I tend to be more conservative, a 'clumper' but with all the hemipenal studies, the Genus Varanus is being split into several super-complexes - and one I disagree with as it does not allow for behavior, distribution, etc, only 1 form of morphological key examined, and I do not think hemipenes entirely designate a species as such = does it for homo sapien and other primates? I think not, other factors contribute to speciation in my book.

cheers,
mbayless

Thank you for your quick reply. Is the study involving the three subspecies accepted by international authorities? Has it, for example, been submitted to the ICZN for review? It seems that naming multiple subspecies on the basis of "insignificant" factors (such as color) is becoming a more frequent occurrence. This also happens to collared lizards, where a comprehensive phylogenetic study of systematics is replaced by other studies where the different "subspecies" do not even appear to be in different phylogenetic trajectories.

I congratulate you on your future project and, again, I thank you for your input.

Truly,

Fabian

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Fabián Aguirre
Zookeeper/ Freshwater Aquarist
Department of Herpetology and Freshwater Biology
The Dallas World Aquarium
(214) 720-2224
fabian@dwazoo.com
www.dwazoo.com

Hi Fabian,
Thank you for your kind words - Yes, the ICZN has acknowledged the 3 subspecies as accurate....but that may change in the future....if not by me, then others will follow this up sooner or later I am sure of that.

Cheers Fabian,
mbayless

Fabian,
Pianka and King's "Varanoid Lizards of the World" is not intended to be a new contribution to monitor classification -- instead, the classification used there (mostly) follows the most recent formal taxonomic treatment of the family. That reference is W. Boehme, 2003, Checklist of the living monitor lizards of the world (family Varanidae), Zoologische Verhandelingen (Leiden) 341: 3-43. Boehme recognizes the three subspecies of V. albigularis mentioned by Mark, with ionidesi (from Tanzania) being considered part of V. a. microstictus.

Unfortunately (and inexplicably), Jennifer Ast did not include any V. albigularis in her DNA-sequencing analyses (2001, Cladistics, vol. 17) of the phylogeny of varanids.

Hi Sam,
Thanks for the clarification on this - Bohme's 2003 paper had completely slipped my mind, which slips often~

Too bad (late) Dennis King had not examined V. albigularis more thorougly when he could have - He and I had discussed it in many of our lengthy correspondences between us in the 1980's- 1990's.

Cheers Sam,
markb

This question and the one below, is asked, just about on a weekly basis.

Personally, I could careless what they are officially known as. Officially, the scientific names seem to change faster then the common names. Yet, the animals do not change. I get the feeling they train taxonomist on a yearly basis and they "need" something to classify or reclassify.

The truth is, there are many many regional types of "albigs" and thats what is of interest to me. Whether they want to call them morphs, races, regional types, or subspecies, is all fine with me. But they really should recognize them as something. Thanks and I hope you find what your looking for. FR

When you make comments such as "Officially, the scientific names seem to change faster then the common names" you aren't saying much. But when you diss taxonomists, you're showing how little you care to know, while having no reservations about commenting.

The currently-recognized subspecies here were established in a paper by Robert Mertens in 1963, but Mertens was cautious and regarded exanthematicus and albigularis as regional representatives of a single, wide-ranging species. Where their ranges approach one another in Sudan and (maybe) Ethiopia, you have big 'exanthematicus' and small 'albigularis' that are also very similar in other features. They aren't common there -- look at Mark Bayless's very comprehensive paper (2002) on the distributions of all Varanus species in Africa (J. Biogeography 29: 1643-1701) and see how many specimens have ever made their way into museums from Sudan and Ethiopia.

It was Boehme (1988) who next took a hard look at the exanthematicus-group monitors in NE Africa while trying to decide if the specimens from Yemen should be described as a new species, or as another regional variant in the exanthematicus group. Boehme decided that albigularis and exanthematicus were in fact different species (as was V. yemenensis), and that's been accepted for the last 15 years.

All of this is based on morphology, scale counts, hemipeneal features and so forth, and it would be very nice to see some DNA sequencing work done on the exanthematicus group. It's a large job -- are you offering to go to Mauritania, Burkina Faso, Nigeria, Zaire, Chad, Sudan, Ethiopia, Somalia, Uganda, Zimbabwe, Mozambique, Angola, and other garden-spots to collect monitor DNA? No? Stand up, Frank, why not?

Before you take cheap shots, show us that you know what you're talking about.

While Frank does seem to say some off the wall things (as we all do) this is not one of them.

Frank hit the nail on the head. It doesn't matter what you call it... just call it something and stay with it.

I'm under the impression that taxonomy was created to facilitate communication. It doesn't seem to be working or the main point has been lost.

Ironically, those that do this as a profession can't seem to come up with a single answer.

If you're ever bored, ask for a (notice i didn't say 'the') definition of a species on a Taxonomy listserv and then sit back. I did this once about 3 or 4 years ago and it wasn't pretty.
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Ed
Tortoise_Keepers-subscribe@yahoogroups.com
Trying to keep the fun in Chelonian care

....and defining what 'species' is is confusing. We have only had since 1766 or so to discuss this concept and its various applications with technology to figure it out, and I suspect we will not define it for a few more....as Charles Darwin and Alfred Wallace said, (paraphrasing) 'Variety within a race (= species) is normal', and that variety is what we are having trouble with - where does a variety become a species, and under what scenarios has it become so? A Wonderful book on evolution and its complixities written for anyone who like Science is, "The Beak of the Finch".

Back to varanids: Today the Order of the Day is how their hemipene structures are designed and shaped determines who is related to whom, and so on....personally I believe this to be only 1 aspect of their speciation, and not the total absolute determining factor of this Genera.

cheers,
mbayless

In studying the structures of various varanid hemipenes, does the difference in structure at all (other than very obvious incompatibilities) suggest the ability or preclusion from copulating with another varanid species? If the answer here is "yes, there are species that have structures that present significant incompatibility with the opposite sex of another species, precluding the ability to mate" (god that's long winded) I would expect this to be definetive support for separation of sub-species. I think this would be most applicable between species that are currently consedered related.

I do not at all have enough knowledge of hemipene structures, or toxonomy for that matter, to offer any accurate examples, but in ignorance I'll offer this;

prior to v. albigarius being separated from exanthematicus, a study of sexual organs shows physical impossibility of fertilization or mating = different species, argument over.

Hopefully you see the question/point through the ignorance.

Hi,
No ignorence at all in your question, and as for long winded, I know the type! ....

Yes, there are differences in hemipenal morphology and even morphometrics among closely related species; take the V. prasinus complex: V. macraei has larger structurally very different hemipenes from either V. prasinus or V. beccari; V. beccari hemipenes are smaller than either V. prasinus or V. macraei and are very similar to shape to V. prasinus, hence the viable offspring Mike Stafani got when he crossed green x black morphs. But simply because a species can breed across species' lines does not mean it is 'closely' related to it - only hemipene structures and female acceptance allow it to happen - if fertile offspring are borne, then maybe this hemipene idea needs to be re-evaluated as I said post above it is the Order of the Day, and one I do not entirely accept at entirely correct, based only on 1 feature of morphology.

Like the V. gouldii complex, they are clearly related to one another, but their hemipene morphologies are abit different when you look at V. rosenbergi and V. gouldii forms; as for V. flavirufus and V. rubidus, I believe these to be merely eco-morphs of V. gouldii, and just junior synonym names for V. gouldii. The V. panoptes issue is more complicated as distribution is conflicting somewhat...and that subject is still under review by the Australians, chiefly by Graham Thompson, a damn nice guy who knows his goannas.

Did I answer your question? Im not sure....?? The v. albigularis complex was initially based on snout-shape and grouped with V. exanthematicus in 1905. Mertens established this in 1942, 1963. In 1981 Bill Branch noted differences in hemipenes among the 'Platynotan' varanus - between V. exanthematicus and V. albigularis group - hence they were split, and assigned their own complex. I conclude the albigularis group is a single complex as there is no (= -0-, zero) geographical separation between the complex anywhere across Africa (Bayless, 2002), or in climate (Bayless, 1997), (but may be for V. yemenensis) and is a single species, with V. yemeneensis as its closest out group; I believe V. yemenensis is the relict group and common V. albigularis is its outgroup or sister species. I try to stick with the Scientific Methodology to the letter, and it is a very sound formula for finding facts....and also a great deal of fun!

Cheers,
mbayless

Nice post Mark, and I only disagree on one small part, todays choice is not hemipene structure, its DNA relationships and it will also be tomorrows. So Mark, sit back, buckle your setbelt and get ready for a bumpy ride, scientific naming is going to go thru some huge changes. Thanks FR

Well all this is just facinating, but for an old country bumpkin like myself, I'll stick with calling Fluffy a blackthroat and Baby and Sassy my savannahs. I don't need fancy names like V. Exanthematicus or V. Albigularis to recognize my lizards.
Ya'll try too hard with all the big words. I am so glad I am me and can understand simpler things like watching my animals to see what they do,what they like and dislike.
They will tell me more than any book ever written. Nobody knows a monitor quite like a monitor
It's really not that hard.

Scott
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Do not meddle in the affairs of dragons, for you are crunchy and taste good with ketchup.

That's all fine, Scott, and I can understand where you are coming from, but there are very good reasons behind using scientific names rather than common names.

Australia was colonised by Brits a couple of hundred years ago. Many of them were clearly homesick and so decided to name all of the animals after familiar English animals. Consequently we have robins, bream, minnows, 'oaks', tortoises and magpies, yet don't really have any true robins, bream, minnows, oaks, tortoises or magpies. What we have are entirely different, unrelated animals that bear some vague resemblance to these other species.

Let's have a look at some examples using fish names between the US and Oz.

Take a deep breath... here we go...

Our bream is what you in the US would call a porgy. Another of our porgies is called a snapper but it bears no resemblance to what you would call a snapper, which is what we call red emperor, unless it is one of the smaller species of that group, which we might also call snapper. Our grey nurse shark looks nothing like your nurse shark, but is what you would call a sand tiger, your bluefish is our tailor, our gar are your half beaks but your gars aren't found here, our cod is your grouper, your cod is our beardie (or ling), our groper is your wrasse, unless it is a Queensland groper, in which case it really is a grouper -although some might call it a giant sea bass - but our small wrasses are still wrasses. We don't have your freshwater bass, you don't have our freshwater bass and the same goes for your/our minnows, but our minnows aren't really minnows and belong to a family that is only found here and in South America and are distantly, vaguely, related to your pike - which, of course, bear no relation to our pike.

Confused, yet? Let's look at monitors.

What you call a tree monitor is skinny and either green, black or black with yellow or blue spotting and comes from PNG or Indonesia. What locals here call a tree monitor is what you or I would call a lace monitor. What you would call a racehorse goanna is a small monitor sometimes known as a freckled monitor, but for many people in Australia it's another name for the sand goanna. what you call a sand goanna is what most Australians would call a sand goanna, except for those living up north which would be looking at what you would call an argus monitor but call it a sand goanna, anyway.

All of this can be rectified by using scientific name. Regardless of whether or not the subspecific names get changed periodically, for the most part the scientific name of a species is fairly stable and is consistent from one country to the next (we'll ignore the Varanus gouldii/panoptes fiasco of a few years ago for now )

forgot I threw the 'oak' example in there

Hi Scott,

Yes they can tell us many wonderful things, like when they are in estrus and stink up the house like roasted almonds, or tick grooming, removing and killing the ticks upon themselves (Williams and Bayless, 2000) - many things we can see them do in captivity we will never see in the wild, and if you something you have never seen them do before, write it down, check with others and publish it = its great to share this kind of stuff with others whenever possible = it also gives the 'academics' more things to think about sometimes...some of us academic types do/have keep varanids you know! We just don't watch them in the wild/on animal planet or from forums like this!

cheers Scott,
mbayless

What I end with is much what you will get unanswered questions and some great references from some good people and sources, as well a partial understanding of what status they are but always in change from month to month. I still dont understand the actual differences completely between V.Albigularis and V.A.Microstictus, the Ionidesi is considered a different color version etc of the Albigularis, or at least used to be, who knows, I wish someone could answer that question and show picture examples of each as well detailed descriptions of what the differences are. Angolensis I dont remember if Ive ever seen a picture yet.

Hi Shvar,
It is complicated, as the animals themselves have such tremendous variety in color, size, head-size, scale size and so on...across an enormous Continent that averages 3000 feet above-sea-level, and yet has regions below sea level across the Continent....all where V. albigularis can be found. In some places, like the Ruzizi Plains, you can find morphs of V. albigularis, V. exanthematicus, V. ocellatus; in South Africa are populations of V. ornatus, a rainforest dweller of equatorial Africa.

And then there are the 'other' Varanus reports, and 2 of them are proof of the pudding of their existence, with 6 x 6 photos I have in my possession...Africa is a terribly old ancient Continent, and I am certain she still has many secrets she is keeping close to her heart, and some of those are Varanus.

Cheers,
mbayless

This thread has been moved from the Monitors forum.
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PHWyvern