Tapinauchenius gigas

[ornithoctonus]

Hi everyone here is a pic of T.gigas my favoret South American arboreal sp. So I hope you like this sp. thanks.

[Ray Gabriel]

Nice pics,

Ok lets try to get some debate going.

I DO NOT think T. gigas and T. eleanae are "true" Tapinauchinus.

I think they are more closely related to either Psalmopoeus or Avicularia.

What do others think?

Ray

[Michael Negrini]

Ok lets try to get some debate going.

I DO NOT think T. gigas and T. eleanae are "true" Tapinauchinus.

I think they are more closely related to either Psalmopoeus or Avicularia.

What do others think?

Ray

Hello,

I think you're right Ray, if you look at the juvenile pattern of T. gigas it's so close to young Avicularia (or later in A. minatrix) that we can think they are related. I think T. gigas is "canopy Avicularia", but maybe we don't have all the pieces of the Aviculariinae subfamily puzzle to understand it all

Michael

[Adam Smith]

They have Avicularia characteristics but I think think they are true Tapinauchinus

[ornithoctonus]

Hi

Hi Guys thanks for responding to my thread and I'm glad you like this sp. Now Ray I am up for debate but as some of you will know nearly all of my spiders are old world and I'm fine with debates on the old worlds but you will have to help me out on the new worlds, as I have never looked in to the Toxinology of many new worlds. The only time I had a look was when I wanted to know more about the family Psalmopoeus and that was only becouse its subfamily is Selenocosmiinae, but any imfo I could learn about Tapinauchinus on the Toxinology side of thinks would be cool thanks. :P

[Chris Sainsbury]

looks wise I would tend to lean towards Psalmopoeus especialy in regards to the abdomens as they seem to lack the 4 little indentations that the other Tapinauchinus sp. have.
I think that not having urticating hairs placeses them further from Avicularia than it does from Psalmopoeus.
I know that in some Tapinauchinus sp. you can find rudimentary stridulating organs so are these found to be larger or anything like what are found on Psalmopoeus sp. in the the two species in question?

I don't believe that the genus Tapinauchinus even belongs in the Aviculariinae subfamily due to the lack of urticating hair etc and from what I have been told by people who have knowlage in these things.
With this in mind could they be a kind of `link´ species that bridges the gap between Psalmopoeus and Tapinauchinus? A couple of those gray area spiders that are on the outskirts of a genus where one genus ends and another begins (in a taxonomy way)?
I this was true would not their location in the world, in regards to other species and genuses back this up or play it down?

Anyway I havn't got a clue!
What was the question again?

[ornithoctonus]

Hi

Hi Tescos so dose this mean we might see the end up in the subfamily Selenocosmiinae like Psalmopoeus or am I geting it rong please tell as I think this needs to be looked in to more but if this is right then its quite weard how one can be so closely linked to one another anyway speek to you later thanks.

[Chris Sainsbury]

Not for me to say either way.

[Oderus]

Like Ray and others i feel T.gigas and T.eleanae are not to close to the other Tapinauchinus due to there juvenile markings, however other then that i don't think there are huge differences between the two tap species groups (bare in mind tho im not a taxo and iv only looked at the bits of one species from each tap "species group"), but we can also say that about Psalmopoeus vs Tapinauchinus too with both seeming very close to each other .

Which if you look back at the juv markings of T.gigas and eleanae would make sense, if we take the lyra on Psalmopoeus to be a fairly recent thing (i believe it is compared to that of the old world Selenocosmiinae) and most of the Psalmopoeus have markings vs most of Tapinauchinus that do not we could see T. gigas and T. eleanae as possible relations to the ancestors of the modern day Psalmopoeus, only prob there being iv never seen anything that looks close to Psalmopoeus lyra on T. gigas only some setae that is a bit darker and thicker looking then some of what surrounds it (could be iv just missed it or have had odd one's next time i have a moult il look again), however if T. eleanae has something more hidden on it's maxilla then the link with the abdominal markings could be right.

Or im talking out my arse again .

Cheers Bill.

[Chris Sainsbury]

Interesting Bill
Looking at the countries of origin of the different species of Psalmopoeus, Tapinauchenius and Avicularia it seems almost as if Psalmopoeus starts of in the West Indies and Central America then almost stops around the north of South America and turns into Tapinauchenius, Then they in turn go on into the main land South America to turn into Avicularia.

Off course this is only a very very broad ruff look at this as there are species of each genus that are found in the same countries as each other etc, but this kind of makes sence of what (I think Volker) said to me about how species of Selenocosmiinae (Psalmopoeus) got to the West Indies and Central America through contential drift.
If you look at it in this broad way its as if maybe Aviculariinae evolved from Selenocosmiinae with Tapinauchenius as maybe one of the cross over species?
Any thoughts on this anyone? (thats if you can understand any of what I have writen, because I'm having problems understanding it myself! )
Cheers
Chris

[Oderus]

Interesting Bill
Looking at the countries of origin of the different species of Psalmopoeus, Tapinauchenius and Avicularia it seems almost as if Psalmopoeus starts of in the West Indies and Central America then almost stops around the north of South America and turns into Tapinauchenius, Then they in turn go on into the main land South America to turn into Avicularia.

Off course this is only a very very broad ruff look at this as there are species of each genus that are found in the same countries as each other etc, but this kind of makes sence of what (I think Volker) said to me about how species of Selenocosmiinae (Psalmopoeus) got to the West Indies and Central America through contential drift.
If you look at it in this broad way its as if maybe Aviculariinae evolved from Selenocosmiinae with Tapinauchenius as maybe one of the cross over species?
Any thoughts on this anyone? (thats if you can understand any of what I have writen, because I'm having problems understanding it myself! )
Cheers
Chris

No sounds like it could be a good idea to me Chris (ok i did think the same thing myself in the past ) but that would indicate reversal had taken place with Tapinauchenius losing there stridulating organ in the same way the Stromatopelminae may well have lost there's compared to the Harpactirinae, how early in development these simple stridulation organs in Tapinauchenius appear in there development may be a clue, if it can be detected very early then maybe it was more developed in common ancestor and simply became redundant over time .

But things are rarely as clear cut or simple as they seem, but the fact that many Psalmopoeus will take to a more terrestal life style (even noted in the wild) might indicate stridulation could be more handy if stuck a half burrow in a tree stump then living high in a tree, again pointing the other way.

I have to agree with Steve's views over the placement of the lyra themselves in Psalmopoeus (oringating as they do from the maxilla fringe and not above it in the Asian Selenocosmiinae) i don't know why i never spotted this myself maybe because my lights are only half on most of the time , however i do also find it interesting that the two Psalmopoeus species i keep both show what appear to be normal setae at the tips of some of there lyra were as Asian Selenocosmiinae have a spine at the apex or nothing, of course Pocock also noted this sometime ago but i don't think he read anything into it, but im thinking of men and monkeys here with possable resent changes from normal setae to thicker spines.

But it is also possible for young Selenocosmiinae when developing to grow setae in the place were a lyra will later grow (from the same visable growth point in the exo) iv seen this two times once in a Chilobrachys and right now a Selenocosmiinae gen "andsti" (il try to get a picture later if anyone is interested but the moult is a very bad way) but as some Selenocosmiinae also have setae on the maxilla were Psalmopoeus do not (slap over the lyra themselves that is) i don't think this can really be viewed the other way round as a possible link.

I think the fact the male genital's of both Psalmopoeus and Tapinauchenius are both simple and without keels like those of the Aviculariinae which is there geographic bed fellows can't be totally discarded also tho i still don't think they should be placed there (Aviculariinae having type II urticating setae and are also said to lack any leg spination) were on the other hand we can see quite complex male and female genitals in the Selenocosmiinae (in fact very complex in Poecilotheria and at least one Indian Chilobrachys that's common in the hobby).

All in all i don't really have any answer to even after all that typing .

Cheers Bill.

[Chris Sainsbury]

Cheers Bill
Really nice information there about something I wouldn't (proberly couldn't) even begin to look at. After reading what you have writen about 20 times I am now understanding (with the help of a few books lol) what you are getting at.
Although you say you don't really have the answer it does I think make for interesting reading even if it is rather confuseing. I suppose at the end of the day much of this topic can only really amount to guess work all be it educated guesses where much of evolultion is involved.
Theres not really much that I can add to this now though as it is going way way beyond my knowledge of spiders and into the relms of taxonomy (you and me both know what I think on that ). I hope that someone who does have an idea about this kind of thing can reply to this thread, as even though it takes me a while to understand what is writen it is I think really interesting.
Cheers
Chris

[Oderus]

Well i would not read to much into everything i write as you well know Chris , apart from the lyra differences which are not my ideas anyway i may have been talking a load of bo'locks really .

I have seen one more thing of interest in these two genera myself (if im not very mistaken) but be they Selenocosmiinae or not it could be viewed as reversal to a state found in a older group due to it's usefulness in an aboreal life style (pretty sure Richard will know what i mean) and therefore not very helpful in telling who's closer to whom.