Where to find Diplodactylus Galeatus

[GeckPhotographer]

Ok, so yesterday a friend in Australia put up some pictures of captives he'd just gotten (this friend is Sam who's posted in this thread, perhaps he'll put the pics up here???), which I initially ID'd as calci, but after some discussion bent toward furcosus. This discussion brought up some things that would strongly influence that post I made the other day, but only in the area of ID between furcosus and calcicolus.

Specifically furcosus represented in the paper and those individuals I have seen personally are indeed much less patterned than they can get.
This picture by Jordan de Jong show's how patterned they can get. (I am hoping that since I'm directly linking to his picture, not actually using it this doesn't break copyright?)

IMG_1862.jpg by Jordan de Jong, on Flickr

Furthermore it appears that D.calcicolus do not have bifurcation at the nape but that the appearance of this shown in some pictures is caused by extreme broken pattern, not 'real' bifurcation.

Pictures at these links showing just how messy this is.
http://members.iinet.net.au/~bush/cascades.html
Diplodactylus calcicolus photo - Ray Lloyd photos at pbase.com

Based on these changes to my understanding of their morphology. (Please keep in mind I've never seen calcicolus in the flesh, it is a strong weak point in my understanding unfortunately). I would most likely change my mind of those I ID'd the other day as calci to furcosus, based on them having true nape bifurcation, and the base colour of their dorsal and lateral surface is fairly constant, not messily flecked like calci are supposed to be.


Now onto Sacha's geckos.

I would ID that as D.furcosus. Why?

Bifurcation of the nape is very strong and distinctly part of the vertebral line not due to pattern 'break up'. This occurs to my (current) knowledge in only D.granariensis and D.furcosus and ALWAYS occurs in furcosus while only occasionally in granariensis.

White spots on the flanks are strongly circular, distinct and darkly edged. This is extremely similar to the WT furcosus shown in Jordan's picture, which is possibly typical of the population captives were established from.
In D.granariensis the pattern on the lateral zones expected would be dull white spots not particularly formed into circles more like what I call "ghost spots" (non circular but strongly white spots would be indicative of ornatus, but it clearly isn't that.)

Because I saw that they should have n=36 while the other species are n=38

D.furcosus are 34, D.calcicolus are 38, and D.granariensis 36 according to the paper. (Interestingly vittatus and wiru are both also 38 and are quite morphologically similar, possibly a direct geographical isolation???)

Now onto a different point you made, the species karyotype. You're right that the chromosomal number is different between the species, and that this could be used to ID between furcosus and calcicolus (which I personally believe are the two confusing species, I think granariensis is quite obviously morphologically different). This however is probably going to end up fairly expensive if you want to do it for every individual coming into your collection, that's your problem of course .

Something interesting to consider is that when this paper published there was some skepticism among certain people believing that furcosus, calcicolus, wiru and granariensis could probably hybridise in captivity.
Obviously the karyotypic differences between some indicate it unlikely but I would definitely like to see the experiment done. (I'm not particularly a geneticist, but even more interesting would be to look at what chromosomes those with lower 2n counts are missing, perhaps through clever analysis this could be a good example of speciation due to "spontaneous" (I obviously assume some natural condition, cold, chemicals, whatever caused this) chromosome addition (this can cause due to problems occurring in meiosis, although it's assumed to be rare). Since stone geckos are clearly a monophyletic group (Look up studies on Diplodactylus, Lucasium split if you want to research this), this could be very interesting if it could determine whether speciation occurred followed by karyotype mutation or karyotype mutation caused speciation. (Much like the polyploidy speciation model supported by Neobatrachus frogs.)


Sorry, I realize most of what I just said was questions, not answers, and I know my understanding of such concepts aren't particularly advanced, but once I started thinking I had to write it.

 

[SHzac]

D.furcosus are 34, D.calcicolus are 38, and D.granariensis 36 according to the paper. (Interestingly vittatus and wiru are both also 38 and are quite morphologically similar, possibly a direct geographical isolation???)

Now onto a different point you made, the species karyotype. You're right that the chromosomal number is different between the species, and that this could be used to ID between furcosus and calcicolus (which I personally believe are the two confusing species, I think granariensis is quite obviously morphologically different). This however is probably going to end up fairly expensive if you want to do it for every individual coming into your collection, that's your problem of course .

Oh I know that this would be expensive, but in the lab course of a colleague they karyotype Drosophila & Co. Thus, some other tissue would not bother I think. I am going to ask him if it is possible to involve it in the practical course. If not I would find another way. If you are right about the species the karyotype 2n=34 would be the final prove.
I'll see...

Something interesting to consider is that when this paper published there was some skepticism among certain people believing that furcosus, calcicolus, wiru and granariensis could probably hybridise in captivity.
Obviously the karyotypic differences between some indicate it unlikely but I would definitely like to see the experiment done. (I'm not particularly a geneticist, but even more interesting would be to look at what chromosomes those with lower 2n counts are missing, perhaps through clever analysis this could be a good example of speciation due to "spontaneous" (I obviously assume some natural condition, cold, chemicals, whatever caused this) chromosome addition (this can cause due to problems occurring in meiosis, although it's assumed to be rare). Since stone geckos are clearly a monophyletic group (Look up studies on Diplodactylus, Lucasium split if you want to research this), this could be very interesting if it could determine whether speciation occurred followed by karyotype mutation or karyotype mutation caused speciation. (Much like the polyploidy speciation model supported by Neobatrachus frogs.)

Sorry, I realize most of what I just said was questions, not answers, and I know my understanding of such concepts aren't particularly advanced, but once I started thinking I had to write it.

I would say, this is pretty advanced for most of the people reading a gecko Forum
Anyway... I agree about the speciation hypothesis. Furthermore I would say that the different chromosome amounts are preventing sympatric species according hybridisation events.
This could be part of a sympatric speciation.
Do you (or anybody else here in the forum) know about other markers? I could perform a (or some) PCRs on them to get some evidence... but up to now I couldn't find published primers or species specific DNA sequences.

Okay. Very interesting topic.
Cheers and thanks for the input!
Sacha

 

[SamNabz]

Great posts, Stephen, and definitely a subject that needed to be touched on.

Here are the pics of the 1.2 D. furcosus I purchased recently which were sold as D. g. granariensis.

The pattern on the male in the second pic definitely resembles that of calcicolus; however, the nape bifurcation is what veered our decision back to furcosus. Also, the breeder of these geckos has been selectively line-breeding his stock for the 'spotted' patterning.

Single Female

Male (left) Female (right)

And here is another female D. furcosus purchased elsewhere which is from WC parents: