Unknown Ornithoctonus from asia

[Crotalus]

The concept of species is not written in stone, there are examples of different species of snakes that breed fertile offspring.
Have anyone breed CB hybrid spiderlings to see if they are fertile or not?

/Lelle

 

[Skuromis]

Hi!

The problem is, that then names for the different Chilobrachys Species, you've used, are only given by Pettrade dealers.

Yes I know and I'm looking for the real identity. One is an adult female and the other a juv. male. So should I try to mate them (later)?

In most cases there are only two different Species of Chilobrachys available in the european Pettrade.
The large lighter brownish one and the dark one with the noticeable stouter and hairier front legs in comparison to the rear legs.

That makes me feel to try ;O) But I cannot be sure.

I know the real identity of both Species, but - as I've told above - at the moment I have to be very careful in telling such results in the forums, because I get the impression that Grandpa steals my results!

And this makes me angry :O/ How to say, erm, evil Granpa.
But maybe I can send you a molt of both (when they are going to molt again) and you tell me, if I should or not ;O)

 

[Theraphosid Research Team]

Hi Sukromis,

if you like, you can send me an exuviae and I can try to identify it (use the adress which is given in the ARACHNE Magazine - I think you are a member of the DeArGe!).

@Michael & Lelle:

If you breed two organisms, which were formely described by subjective morphological characters (it doesn't matter whether they are known as different Species or genera, in both cases the taxonomically rank was defined by morphological characters), and they will produce fertile offprings, should we better think again about the Species/generic (based on a morhological point of view) definitions of he organisms, or should we change the Species concept, so that the old opinions concerning the Species/generic rank of the organisms will be carry on?
In other words: should we interpret the result of the crossbeeding experiment in the backround of the Biological Species concept, or should we change the BSC in the backround of the stability of the former opinion/classification of the crossbred Taxa?????

Good evening, Voker

 

[phormingochilus]

Hi Volker

This Ornithoctonus sp. "Asia", is this the one from Carl Portman? (the one that made trapdoors?) Or some alltogether other one?

AND - we need to finish the last drawings! ;-)

Lelle and Jacobi
It is not so much the cases were different forms creates offspring (viable or not), that are indicative of speciation (as there may be no need for biological mating barriers when geography in effect does this) but the cases were mating and/or breeding is impossible, in particular where two assumed species are sympatric. Here it can clearly show if the differences of the forms are due to colour/morphological variation (interbreedable) or speciation (nonbreedable).

Regards
Søren

 

[Steve Nunn]

the cases were mating and/or breeding is impossible, in particular where two assumed species are sympatric. Here it can clearly show if the differences of the forms are due to colour/morphological variation (interbreedable) or speciation (nonbreedable).

Hi Søren,
I agree, but in a situation where the entities are sympatric, then there is good evidence in place for complete speciation, or else the two forms would not exist in sympatry. It's those allopatric and particularly parapatric colour/size forms that can raise the most difficult questions.

Look at Brachypelma, whether we like it or not we may need to look at the majority of this group as one or two superspecies groups in future, particularly when looking at recent DNA research (Longhorn, yadda yadda). I believe the colour forms are most likely stable, but doesn't mean they are different species (as you know)....

Steve

 

[Crotalus]

Lelle and Jacobi
It is not so much the cases were different forms creates offspring (viable or not), that are indicative of speciation (as there may be no need for biological mating barriers when geography in effect does this) but the cases were mating and/or breeding is impossible, in particular where two assumed species are sympatric. Here it can clearly show if the differences of the forms are due to colour/morphological variation (interbreedable) or speciation (nonbreedable).

Regards
Søren

I dont agree that it clearly shows here.
If it was 100 separate breeding couples then you might get a valid result of the mating attempts but not from one or a few.

 

[Crotalus]

In other words: should we interpret the result of the crossbeeding experiment in the backround of the Biological Species concept, or should we change the BSC in the backround of the stability of the former opinion/classification of the crossbred Taxa?????

Good evening, Voker

There will allways be different opinions on what a species are and there are several concepts and not only one.
Either the concept that two species cant breed fertile offspring is wrong or the species that did that is not two species at all.

 

[phormingochilus]

So what is your opinion Lelle ? ;-) What hypothesis do you reckon is the most useful if any - and why?

Regards
Søren

There will allways be different opinions on what a species are and there are several concepts and not only one.
Either the concept that two species cant breed fertile offspring is wrong or the species that did that is not two species at all.

 

[Theraphosid Research Team]

Hi Volker

This Ornithoctonus sp. "Asia", is this the one from Carl Portman? (the one that made trapdoors?) Or some alltogether other one?

AND - we need to finish the last drawings! ;-)


Regards
Søren

Hi,

yes, I know. I'll do my very best!
I only possess pictures from that Ornithoctonus from Carl, never saw the female. But from the pictures, I would say that it isn't conspecific to that one.

Cheers, Volker

 

[Steve Nunn]

Either the concept that two species cant breed fertile offspring is wrong or the species that did that is not two species at all.

Hi Lelle,
This is not totally accurate. With snakes in particular the crossbreeding has been performed in captivity, in which case there is every argument to say the mechanism that prevented these species from crossing in the wild was removed in captivity. That said, there is no support to doubt the BSC based on your point

I'm aware that certain species will cross in the wild via convergence, but there are exceptions to every rule in biology. This science is not so black and white as everyone would like, this is not chemistry after all!!

With all the species defintions we have in our day and age, you will not find one that applies to each and every species on the planet, the concept just does not exist, due to anomilies that will always arise in nature.

Cheers,
Steve

 

[Crotalus]

Hi Lelle,
This is not totally accurate. With snakes in particular the crossbreeding has been performed in captivity, in which case there is every argument to say the mechanism that prevented these species from crossing in the wild was removed in captivity. That said, there is no support to doubt the BSC based on your point

I'm aware that certain species will cross in the wild via convergence, but there are exceptions to every rule in biology. This science is not so black and white as everyone would like, this is not chemistry after all!!

With all the species defintions we have in our day and age, you will not find one that applies to each and every species on the planet, the concept just does not exist, due to anomilies that will always arise in nature.

Cheers,
Steve

The mechanism would be a mountain range etc in the wild but that solely doesnt make them different species.
What im saying with the snake example is the difficulties of define a species.
Crosses in the wild are quite common esp. among some genera of snakes but this doesnt automatically say they producing fertile offspring.

Soren,
offcourse there are several key factors such as isolation, changes in morphology, capability of breeding and im sure a whole lot more. Even with as many factors as possible there will allays be exceptions. What Im saying is a single case or a few cases wont prove much.

 

[Theraphosid Research Team]

Hi,

however, if I have the choice to make a Species description which based only on the morphological analysis of the Specimen, or which based on the morphological analysis AND some indications about their reproductive behavior, I would prefer the last one!

Cheers, Volker

 

[Bearo]

Hi,

however, if I have the choice to make a Species description which based only on the morphological analysis of the Specimen, or which based on the morphological analysis AND some indications about their reproductive behavior, I would prefer the last one!

Cheers, Volker

Short and simple hehehe

 

[M.F.Bagaturov]

Sorry messiers...

I know the situation is not so clear that's why Lelle try to emphatically told You his point on the subject discuss.

Maybe some of You knows my point on this also about the difference I believe in speciation of the different theraphosid fauna of the World. Thus gives me some clues that this for sure works with asian and possibly african species, but not unfortunately with americans, since so I have at least two evidences of fertile B. albogans cases here in Russia.
But I do not believe B. albopilosa and B. vagans is the same species, only differenet color forms.
That is a question...

 

[Steve Nunn]

Hi Mikhail,
There is some evidence that the spiders from the NW around central America are undergoing explosive speciation, the mechanisms are most likely not quite in place, so crossing of forms/species happens regularly, even in the wild.

This example doesn't really argue the BSC either, in explosive speciation many new forms arise, some interbreed back with other populations, others develop further, into biospecies within their own right. There are numerous genera in the area most likely in the process, such as the Avicularia, etc..

This is why there is some debate about the Brachypelma at the moment, the genus is not defined enough we can be postive the classification of them is right, if anything it gets more interesting with Stuart Longhorn's work, which clearly shows the close relationship between several members of the genus.

Steve

 

[M.F.Bagaturov]

Yep, Steve.
That's exactly what I also told and this is I suppose why Lelle arguing on this subject.
Just to show that all this taxonomy not so simple even for Volker , but indeed for him some easier than for Stuart, i suppose... including recent A. Locht synonymization of B. ruhnaui (really doubt one to me taken into account of the mess with types of B. "pallidum" and albiceps and also obviousely do not quite well studied both genera features).

 

[Crotalus]

Yep, Steve.
That's exactly what I also told and this is I suppose why Lelle arguing on this subject.
Just to show that all this taxonomy not so simple even for Volker , but indeed for him some easier than for Stuart, i suppose... including recent A. Locht synonymization of B. ruhnaui (really doubt one to me taken into account of the mess with types of B. "pallidum" and albiceps and also obviousely do not quite well studied both genera features).

No thats not the reason. My arguments can be applied for any taxa not only theraphosidae.
But Id like to hear more about the spiders from the NW around central America are undergoing explosive speciation (yes I copy & pasted that long part from your post Steve

/Lelle