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Tylototriton ID Needed

Azhael

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I see what you mean, thank you for taking the time to answer :)
Although i understand your commentary about the criteria for species status being the same as for subspecies i´m not sure i can invalidate the concept of subspecies altogether. I´m thinking about something like some of the subspecies of I.alpestris. If there is geographical isolation (which there is) and there are minor morphological differences which are specific of each group, i can understand why that meets the criteria to consider them independent species, yet the differences seem so utterly insignificant (even though at a genetic level there may be more significant variations, despite the fact that they are not reproductively incompatible) that to consider them distinctive species sounds very tricky to me.
Take I.a.apuanus and I.a.cyreni, for example. They are geographically isolated, there is no gene flow whatsoever. They are distinctive from each other, both morphologically and genetically. Would you say these should be considered independent species? Again, i do understand why the criteria is the same, but i´m curious as to why you invalidate the concept of subspecies altogether (if that´s the case). I´d be interested to see what your reasoning is..let´s face it, i want to learn xDD
Sorry for deviating the topic and thank you for taking the time to satisfy my curiosity n_n I´m fascinated by taxonomy but i´m very green, so i really apreciate your input on the subject.
 

frogman

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Those look just like mine!!! Mine are mainly aquatic, how about yours?
 

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FrogEyes

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I am not prepared to totally discard the subspecies concept, though that has in essence been done already by others. It is problematic because the dividing line between species and "subspecies" [and semispecies, superspecies, species groups, species complexes] is entirely arbitrary. The concept is applied when it is difficult to draw a dividing line between the ranges of two species because of the degree to which they merge. Each has a separate and distinct ancestry and set of traits, but identifying where one ends and another begins is hard because of the amount they overlap and interbreed.

The concepts of semispecies and superspecies seem to be applied when the amount of interbreeding or overlap is very small, but so are distinguishing features. Such is the case in the Plethodon glutinosus superspecies [or species complex, as you prefer] and Plethodon jordani superspecies, which together with a couple other taxa can be considered a species group. Each of these superspecies is made up of a number of allopatric or parapatric populations which rarely interbreed, have fairly long histories of reproductive isolation, and which in many cases are very hard to distinguish from one another. In these superspecies, the divergence between groups is also at the lower limits of genetic and chronological differences for species in general, meaning that they went their separate ways a bit more recently than what is usually used as a standard in other species. To deal with these conflicting points, many of these populations were originally described as semispecies - formally somewhere between interbreeding subspecies and non-interbreeding species. In practice though, they have all been widely accepted as full species because people are uncomfortable with using additional intermediate categories, and the requirements of species status have been established anyway.

It is fairly easy to accept as new species those populations which are both isolated and distinct in appearance, not so easy for the others. However, both are equal. Species are biological entities and are "real". They are groups of organisms with a shared evolutionary and reproductive history. All of the various 'species concepts' are not definitions per se, but are means by which WE identify them. The animals don't care. They normally recognize their own species just fine and it's doubtful they count costal grooves or dorsal spots to do so. Among other things, the proof is in the genes they do or do not share, since that establishes whether or not they form an interbreeding population.

I don't have much familiarity with Ichthyosaura [they're illegal here, and I try to focus on Asiatic species anyway], so my opinions on its systematics are few at the moment. From what I recall off the top of my head, some of the forms are less distinctive and isolated than people believe, while there may also be others which are unrecognized but distinctive. Some of the apparent isolation may actually be very recent and human-caused. While in evolutionary terms, that doesn't really matter, it does mean there's a question of what would happen if human disturbance were removed from the equation. Would distinctive animals now at the end points of a broken range, reconnect smoothly and lose their distinctiveness, or would they maintain their independant evolution? We don't really like to recognize a new species now only to have it disappear thoroughly into another in a few decades. Like it or not though, if isolated and distinctive, species status is appropriate. From what I remember, I think it would be appropriate to recognize more than one species in this genus. A compromise might be to treat the adjoining and interbreeding forms as a single species [or more than one], and the isolated forms east of the Adriatic as another species [or multiple species].

My expectation would be for three species, though I question the value of recognizing subspecies east of the Adriatic for every trivial difference between montane lakes. Neoteny, for example, is probably not an important or reliable feature at this point, since it seems to be facultative in a great many salamanders. Surround them by a harsh environment, and neoteny appears. Improve the environment, and it more or less disappears. It can take a long time in a stable environment for a feature to become genetically fixed, and alpine lakes in Europe can't be considered old or stable, since they were buried in ice only hundreds or thousands of years ago. Obviously the newts moved in since then, but became trapped as warming and drying continued, giving an advantage to neoteny.

Another factor at work is human cultural differences. Europeans seem to have a love for subspecies and subgenera and may be reluctant to accept generic or specific splits. That's mostly not the case elsewhere, where fewer subspecies are named, and existing ones are readily raised to species level or discarded altogether. I would admit though, that the diverse topography and environments of Europe could well lead to a large number of valid taxa. I think those attitudes may be changing though, given the increasing number of species splits in Europe - in Hyla, Salamandra, Pseudepidalea [toad subgenera don't work, despite some people clinging to anything toad-like being "Bufo"], Lyciasalamandra, Triturus, Pelophylax, etc. Lacertid lizards are notorious for the number of subspecies named over the years, but I don't know what the current status or trends are for these.
 

Azhael

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You are absolutely right, there is a clear trend (at least i think it´s clear) here in europe of raising subspecies to species status. The case of lacertids, which you mentioned, is perhaps the best example, since the number of species has multiplied in recent years, specially since more serious work has been done with insular populations in the mediterranean.
You make an excellent point when you point out that taxonomy is after all a tool WE use.
As you say, if a population is isolated and distinctive, species status is legitimate, but i still find it useful to use the subspecific level when the genetic distance is small. If we were to give species status to every genetically isolated population in europe we would run out of names (because of the man made isolation you pointed out which is very real).
The arbitrariness of the different taxonomic "boxes" is very clear in the cases of superspecies, like you mentioned. This is perhaps the main reason why i give locality data an increasing importance.
Nevertheless, we have to use some kind of system, and it is indeed an enormously useful one.
Thank you for indulging me :)
 
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FrogEyes

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Those look just like mine!!! Mine are mainly aquatic, how about yours?

It is my experience and that of others I know, that this species does well in a very dry environment. Certainly they take to water, at least seasonally, but I found they did best in deep leaf litter outdoors. Rainfall brought them to the surface. I lost a bunch very quickly when their indoor enclosure was watered, yet they had done very well for a long time when it was almost bone dry. Conversely, they obviously can't survive dessication. I guess the balance is low humidity with access to moist retreats and open water.
 

Viv

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Yeah. Mine don't seem to like water that much. They will go in the water bowl but they spend a lot of time hiding. Either behind plants or under the hide where its dry.
 

FrogEyes

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And it's unlikely that yours is T.kweichowensis either. The vast majority of these animals do not match the diagnosis of that species, one critical point of which is the presence of fused dorsolateral warts which normally form solid orange stripes. Safer to consider these uncertain and most likely undescribed, rather than lump them into a species they don't match just because it's the most similar. That just leads, in the long run, to interbreeding of animals of different species, because people assume them all to be the same.
 

Griffin8891

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Is it possible for there to be variation amongst populations of the same species with this sort of animal?
 

Azhael

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Sure, there is variation in every population (at least any that reproduces sexually, that´s for sure).
The point FrogEyes makes is that it´s too soon to know wether these animals represent a separate species, a subspecies, variation inside the same species, or whatever, so the prudent and cautious thing to do is to consider them as uncertain and don´t go about mixing them with kweichowensis. If people do that, and they interbreed and then we find out that these are a separate species, then that would be a loss because we would have created hybrids that are worthless for either species and that could spread the genetic introgression into other bloodlines. That would be catastrophic in the eyes of many of us.
 

FrogEyes

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Exactly!

I would emphasize though; that when two variants are of the same species, you won't see 99% of one identifiable form identical to the species diagnosis, and then suddenly see [in the pet trade, wild-caught] animals that are 99% NOT consistant with the species definition.

If a species varies, to some degree you should see all variants within a given population. In oriental ribbed newts (Echinotriton and Tylototriton), the number, size, shape, position, and color of the dorsolateral warts is very consistant and diagnostic of each species [see the description of T.notialis for details]. In T.kweichowensis, those warts are red-orange, flat, squarish, and mostly fused together to form red-orange glandular stripes. That's part of the original species diagnosis, and these animals were known to be relatively numerous and widespread even then. In nearly a century, that hasn't changed, and has been almost universally true of animals in the pet trade as well. Fused, red-orange warts. Then suddenly in the last few years, animals in the trade [sold variously as shanjing, verrucosus, or kweichowensis] have nearly universally been intermediate between shanjing and kweichowensis, having discrete, separate lateral warts, but otherwise being colored like kweichowensis. That contradicts both the description of T.kweichowensis, AND the trend within the subfamily for consistant wart morphology within each species. That argues strongly against the two being the same species. It also suggests that the new form is not a hybrid [hybrids are not so consistant in form, nor so numerous usually], and that the two forms come from separate and isolated populations [each has been available in large numbers at one time, separate from the other]. Both of these factors also suggest separate species. What remains to be determined is both place of origin and genetic data to compare with other species. For the purpose of the latter, I have set aside some frozen specimens which I will eventually submit to researchers I know. Perhaps they are already in possession of animals from known locality, and simply haven't published yet.

The bottom line is, there is NO good reason so far to consider these to be T.kweichowensis, and many reasons to avoid calling them such.
 

Griffin8891

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I understand. I was gonna ask if someone has looked at the genetics yet. Keep us posted on what happens with your frozen specimens.
 
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