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Posted by richardwells on May 13, 2003 at 02:30:52:
On the Validity of the Name Oxyuranus scutellatus barringeri Hoser, 2002
In 2002 Raymond Hoser formally described a new subspecies of Taipan as Oxyuranus scutellatus barringeri [see Crocodilian, 3 (1):43-50]. His original description was included within an article that briefly mentioned various aspects of Taipan biology. This article provided no new ecological or biological data on Oxyuranus scutellatus, indicating that he appears to have little direct experience with Oxyuranus himself. Nevertheless, the article included one very important piece of information - Hoser offered his opinion that, by inference, Oxyuranus scutellatus in Australia is a polytypic species. In effect, he claimed that there are two taxonomically distinct populations of scutellatus in Australia - the eastern (nominal) form and a northwestern-northern form, which he identifies for the first time. Further, Hoser actually strengthened this opinion by formally fixing a new scientific name Oxyuranus scutellatus barringeri to this northwestern 'population' of O. scutellatus.
His article raises a number of questions, not the least being - Is this description technically valid under the International Code of Zoological Nomenclature? More importantly, does the description provide a convincing argument to adopt the new taxon, whatever it is called, as a distinct entity of the Australian Elapidae? On both questions the matter is anything but clearcut. Some critics have already argued that from their reading of the International Code of Zoological Nomenclature and Hoser’s article, Oxyuranus scutellatus barringeri is nomen nudum, and such an interpretation of the Code is indeed also possible given the nature of the original description. With what has been made available to date, this is also my opinion. However, I believe that such a determination could be subject to complex argument in the Commission, and a contrary view might also emerge. From my reading of Hoser's article, outside of the issue of its questionable validity under the Code, the new Taipan description isn't at all convincing at this stage - at least not to the point where I can confidently accept it as a distinct entity of the Australian Elapidae. The reason I hold these views follows.
Firstly my own knowledge on the population under question is so meagre that as yet I am pretty much in the dark on any morphological distinctness that northwestern material may possess. The only material that I have examined that may be considered as possibly representing Oxyuranus scutellatus barringeri was a single specimen in the Northern Territory Museum. The specimen that I examined in the NTM in Darwin was from the Reynolds River country west-south-west of Darwin and actually it had such morphological similarities to Taipans from around Cairns that at first I thought its locality data might have been erroneous! The original collector who had killed the snake with a shot-gun blast, described its colouration in life to me. The purplish-brown of the body sounded more like that of a canni than a scutellatus, but the colouration was somewhat different and inconclusive as a preserved specimen in the museum when I examined the specimen in 1977. The body of the specimen appeared to be slightly more angular in shape in places, but Taipans can change so much in body shape with diet as well as both ontogenetically and sexually during their life that I felt it fell well within the range of body shapes of Taipans from eastern Queensland in my opinion. Similarly, the descriptions provided by Butler in 1979 (see Western Australian Naturalist, 14:134) and that in Storr, Smith and Johnstone in 1986 and 2002 (see Snakes of Western Australia, p.196-197) do not appear to contain information that states or even indicates any morphological distinctiveness of such material from that of eastern Australia. So Hoser’s description is all I have to rely upon for guidance here.
The original description of Oxyuranus scutellatus barringeri by Hoser essentially amounts to a description of the holotype but the morphological characters noted are not directly compared with the nominal form. As the description of the Holotype completely overlaps the known morphological variation even within what Hoser himself regards as Oxyuranus scutellatus scutellatus, one is forced to ask how does it differ from the nominal form ? It is clear that he believes that the taxon is distinct but little is offered to support his contention. Hoser’s use of ‘Oxyuranus scutellatus Peters, 1867’ may give us a clue as to a possible basis for the perceived distinctiveness of barringeri. By implication, the use of ‘Oxyuranus scutellatus (Peters, 1867)’ could be interpreted as conforming to a description that purports to show differences between the new taxon and its closest relative - O. s. scutellatus - and this could make the name Oxyuranus scutellatus barringeri technically available under the Code. I think that ordinarily the use of the Authority and Publication Date following a scientific name represents an explicit reference to the data on which a taxon is based. Consequently, it might be argued that Hoser's use of '(Peters, 1867)' following the binomen Oxyuranus scutellatus effectively establishes a reference to that species that contains data that may be compared with his diagnosis of Oxyuranus scutellatus barringeri. If one was to give Hoser the benefit of the doubt and assume that this is what he intended, then an argument could be had that the requirements of Article 13.1.1. are satisfied. However, Hoser has failed to include a bibliographic citation or even a direct reference to such a citation to Peters' 1867 original description of Oxyuranus scutellatus and I believe that this has the effect of negating any protection afforded by such an interpretation of Article 13.1.1. All you see, is all you get I’m afraid. In consideration of the above, I believe that Hoser's own additional statement that the characteristics of barringeri - "fit within the known parameters of other Oxyuranus scutellatus" in the absence of any other supporting data, effectively and unambiguously invalidated his description morphologically. But there is more, because in his original description, Hoser also noted that his new taxon Oxyuranus scutellatus barringeri was isolated distributionally and reproductively from O. s. scutellatus and O. s. canni, and that the new taxon's distinctiveness had been determined by DNA analysis. Perhaps these aspects can save the paper.
On Hoser's justification of a reproductive and DNA distinctiveness for recognising Oxyuranus scutellatus barringeri, well this has more of a ring of prediction to it than fact. I know of no reproductive data that has been published that demonstrates the distinctiveness of different populations of Oxyuranus scutellatus. Further, Hoser's evidence of DNA differences between these populations was unspecified and unreferenced. I ask, what really did Hoser's statement mean when he said that ''the three forms are separated by DNA analysis''? DNA differences can be easily demonstrated even within individuals of a single population, so I really have to know more about this piece of insight. Hoser's bland statement that "The three forms are further separated by DNA analysis." is simply argument by authority - akin to something like "The three forms are further separated by having different souls", tantalising...but of no substance from an evidentiary point of view.
Hoser’s reliance upon distributional evidence has also bee considered. Dr Wolfgang Wuster has communicated his opinion to me on the matter of the status of Oxyuranus scutellatus barringeri and among other aspects, believes Hoser's description fails because 'locality is not an intrinsic character of the taxon'. However, I would tend to disagree because it is not merely 'locality' that Hoser uses as a justification for the recognition of the new taxon, it is 'distribution', and this is what is clearly and repeatedly stated in the original description of Oxyuranus scutellatus barringeri. Nowhere in the Articles of the International Code of Zoological Nomenclature does a consideration of distribution either directly or indirectly invalidate an original description. I believe that 'Intrinsic characters of a taxon' are not just confined to morphological characters in the Code or in the minds of taxonomists. Behaviour for instance (or a worker's interpretation of it) has been used in numerous instances as being a valid consideration in the description of new taxa. I consider that 'behaviour' must be regarded as a character state because it has gained wide acceptance as a valid component of numerous original descriptions. Now this is an important point, because WHERE an animal lives is as relevant as to HOW it lives. Not only has distribution been considered almost continually in original descriptions of taxa since 1758, its omission has in actuality resulted in great confusion at times.
But of this distributional evidence I can only conclude that Hoser's assertion that the taxa are geographically isolated is speculative at best in the absence of more intensive surveys of the northern region of Australia. He might very well be correct but I am not yet convinced. I say this, not because I don't like distributional boundaries as taxonomic characters, but because when it comes to the Taipan, it has been a very difficult species to survey for this kind of data. If distributional patterns are a serious consideration in taxonomy then this aspect demands that it be based upon very solid ground indeed. If such data are included as an effective justification for the erection of new taxa then, like any other character, it should be included as a statement that is unambiguous in its content and clear in its intent. A wishy-washy statement that indicates or states that the overall distribution between related taxa is uncertain not only undermines the value of the distributional data that is used, it also likely fails to meet the requirements Article 3.1.1. of the Code. Hoser is anything but clear in his consideration of distributional differences between the taxa, and I can well understand why. Not only have I been actively mapping the distribution patterns and habitat preferences of reptiles for over 30 years, I have actually lived and collected across the range of the Taipan itself. I can say with certainty that this snake is unlike any other species in Australia when it comes to trying to work out its natural behaviour and ecology. Captive specimens are only a shadow of this animal in the field, and inadequate numbers of museum specimens is problematic also. So I don't really think anyone can confidently state the natural distribution pattern of this species as yet. For instance, Hoser categorically stated that Oxyuranus scutellatus does not occur in northern New South Wales, but it actually does. I am aware of Glenn Shea's article which pointed out the lack of any voucher specimens in existence to support a range extension into NSW but I have seen three specimens from the vicinity of Grafton and I have no doubt as to their identity and provenance. When I first heard that Taipans were in the Top End of the NT and north-western WA back in 1977 I must admit that I suspected that they may have been distinct from those in Queensland - perhaps even closer to canni. Indeed, it was no surprise at all for Graeme Gow or I when we heard in 1978 that Harry Butler had finally secured a specimen in the Kimberley region. After all, Eric Worrell had long predicted that it would be found in north-western Australia and we just assumed that it would be there because of the presence of its known habitat. Its presence in the Top End of the Northern Territory had been known even from the 1930s, when anthropologists working with Arnhem Land aboriginals realised that the species was so well known there that the natives had their own name for this much feared species. Similarly its discovery on Melville Island off Darwin wasn't all that surprising either. Having previously lived in Darwin, I travelled extensively across the Top End searching for reptiles - in particular snakes - and it wasn't too hard to understand why Taipans hadn't been recorded in open savanna woodland near populated areas. Outside of the fact that this species' activity patterns are highly seasonal, it is, as most experienced field herpetologists know, a very shy and alert species which can evade all but the best collectors. In fact, contrary to the view of some that this is a rare species, I would contend that it may be far more abundant in some areas than people realise. But snakes generally don't do well in areas that are subject to fires. In the Northern Territory and the Kimberley region for that matter, the habitats are regularly devastated by fires, both man-induced as well as naturally from the thousands of lightning strikes every Wet Season. Darwin for instance may have up to 18,000 lightning ground strikes within a period of a few weeks at the onset of the Wet, and in parts of the Kimberley, over 20,000 strikes can occur within the same period. When this occurs vast out-of-control fires can burn thousands of square kilometres of habitat and are only extinguished briefly during the rainstorms. Following the Wet Season a second wave of firestorms may rage over the region as a result of the deliberate burning by pastoralists of the luxuriant growth of vegetation that immediately follows the Wet. Thus, the habitat conditions of the region favour the persistence of species of snakes that have access to refuges from the impact of fire, such as rock outcrops. And it just so happens that most sightings of Taipans have been in areas where rock outcroppings are also a feature of the landscape. I actually travelled to the exact place where the NTM Reynolds River specimen had been collected along with the original collector and the traditional aboriginal owners to examine its habitat – it was taken around a rock outcrop on a slightly elevated stony hill (now known locally as Taipan Point) adjacent to an extensive wetland. The dominant surrounding vegetation was savanna woodland, but scattered remnants of monsoon forest also grew along a nearby watercourse. Interestingly, remnants of monsoon forest were also noted in three other sites in the Northern Territory where Taipans have been observed. When I visited the Reynold’s River site, I was stunned how similar its habitat was to other places of savanna woodland in the NT where I had surveyed without finding Taipans. My first impression upon seeing the site was that Taipans could be anywhere in the Top End - even Darwin! I have no doubt that Taipans will be found to be a species that occurs right across the Kimberley Region of WA and over the Top End of the NT to at least the Gulf of Carpentaria. However, this distribution pattern may already have become significantly altered, fragmented by agriculturally-induced change to the vegetation. Hoser also provided a very interesting theory to explain the apparent rarity of Taipans in some areas as well as the apparent fragmented nature of its distribution. He believes that competitive exclusion of Taipans by Cannia australis and members of Pseudonaja may be occurring. Very interesting, but I have kept a Taipan in the same enclosure with a King Brown Snake and if you ask me I would say that the King Brown wasn't all that pleased by the experience! Hoser might be correct, but in the natural conditions of their habitats Cannia, Pseudonaja and Oxyuranus separate quite nicely ecologically. If anything would be doing the excluding I should say that it would be more likely man and climate above all else.
Now I should say that although it is hard to convince me that the north-western 'population' is distinct by the data offered in Hoser's paper, he may in fact be correct. This snake might indeed be a distinct entity of the Australian Elapidae. I just haven't seen enough evidence to believe it yet. In the case of canni however, I am completely convinced that it is a full species in its own right, with its own population variations, and I was quite surprised that Hoser chose to treat it merely as subspecies of scutellatus in the face of even the data in Slater's original description of it.
As Dr Wuster and some others contend, the name Oxyuranus scutellatus barringeri is therefore a nomen nudum, ‘a name that does not exist as far as the scientific nomenclature is concerned’. However, to be fair to Ray Hoser and of course poor Mr Barringer, the name Oxyuranus scutellatus barringeri may be made available simply by publishing another formal description that does satisfy the relevant Articles of the Code. I have already requested Ray Hoser urgently redescribe the taxon with additional data so as to unambiguously establish the validity of the name under the International Code of Zoological Nomenclature. It is pretty clear that anyone COULD publish a description of the taxon should evidence become available that it is distinct from nominal scutellatus. In so doing, they may give it whatever name that they feel is appropriate. Personally, however, if this snake should prove to be a distinct entity, I would prefer that the name Oxyuranus scutellatus berringeri be again used in any such redescription by whoever does it. Perhaps Ray Hoser may like to whip off a quick note on the diagnostic DNA data that he alluded to in his original article and the problem would be solved. I would be interested in hearing from anyone that can support or refute the validity of Oxyuranus scutellatus barringeri.
Richard Wells
