It looks like T's have more than 2 mouth appendages

Gingerfish

Arachnopeon
Joined
Feb 1, 2010
Messages
15
I've been having fun on my uni microscopes, and decided to take a closer look at a tarantula molt. So I take a look at the mouth part and found that there are actually what looks like 'grinding appendages'' under each set of fangs that must help with the grinding and mashing up of their food or it could be stridulating organs but I've never known Golden knees to do that , that must be that weird movement when they move their fangs in and out. I don't know if any one has seen this before, I surely haven't, I don't think its as visible on a living tarantula. Would love to hear your feedback! :confused:
 

Attachments

Fran

Arachnoprince
Old Timer
Joined
Nov 8, 2007
Messages
1,533
REALLY NICE pictures. :worship:

I remmember seen those markings years ago.
 

jebbewocky

Arachnoangel
Old Timer
Joined
Oct 1, 2009
Messages
909
I kind of doubt those are for stridulating, since they don't seem to have anything to rub against. I'm with the secondary jaw idea.
 

Arakatac

Arachnopeon
Joined
Jul 19, 2009
Messages
17
Fascinating! Just an idea, but perhaps those teeth act as grips, like the ridges on a wrench, to hold the food item in place as the fangs pressure it inward against the actual mouth-parts.
 

Salamanderhead

Arachnobaron
Old Timer
Joined
Aug 30, 2009
Messages
410
Wow! Those almost look like teeth. That's amazing, I had no idea those were there. I'd be interested in what exactly they're for.
 

KnightinGale

Arachnoknight
Old Timer
Joined
Sep 16, 2009
Messages
170
Hey, very cool! Thanks for sharing these with us. I agree that they would most likely be for the grip-and-squeeze since they are on the underside of the chelichera. When a tarantula stridulates with its mouth parts it looks like it is rubbing the insides together more than anything on the underside. They don't look to be made for really grinding and mashing up food to me, and tarantulas don't completely mash up their meals like a scorpion does anyway, but I imagine they would rather help keep that struggling cricket in their grip...especially when they are turning them, webbing them and moving them around.
Ok, next quest, check another species and see if they look the same!

Alright, my Ts, which one of you wants to show me your moutharts up close? :D
 

Silberrücken

Arachnoangel
Joined
Feb 17, 2010
Messages
875
:eek: ... this is the most fascinating thing I have seen in YEARS! :eek:

AWESOME pics!!!! Thank you for sharing this with us! :clap::clap::clap:
 

Balkastalkman

Arachnosquire
Joined
Feb 19, 2010
Messages
96
WOW. Thats really cool, I never knew Ts had those. I wonder if they are for gripping prey, or just eating.

Ill have to take a close look at all of my molts. I would like to see if all Ts posses these or just new worlds. Thanks for the pic man.
 

dannyboypede

Arachnosquire
Joined
Aug 22, 2010
Messages
142
Those jaws are for cleaning their legs. Most people have probably seen their T's moving their legs through their fangs. They are combing their hairs, literally. When we have a stuffy nose and can't smell, we blow our nose. One of the only way T's, and any other spider, can sense things, is with their hairs. So, there is your answer. I read it in the Golden Guide: Spiders and their Kin, in case anyone is wondering.

--Dan
 

AphonopelmaTX

Moderator
Staff member
Joined
May 7, 2004
Messages
1,816
They are indeed called cheliceral teeth and all tarantulas (if not all taxa in the mygalomorphae) have them. Only on the largest tarantulas are they visible to the unaided eye but obviously you'll have to move the fangs and setae out of the way to see them. The primary use for them is to grip and masticate prey items in combination with the labial cuspules (the numerous mounds located on the labia). Search Google for "chelicerae teeth" or reference The Biology of Spiders by Rainer Foelix for more info.

The stidulating organs are a type of stiffened bristles/setae and depending on the taxa are located on various locations including (but not limited to) or a combination of the inside or outside faces of the chelicera, pedipalps, trochanter, coxa, and femur.
 

Travis K

TravIsGinger
Old Timer
Joined
Jan 6, 2007
Messages
2,518
They are Chelicerae Teeth and they use them much the same way you and I would use ours. Their main mechanical function is to masticate the prey items to maximize the amount of fluids they can suck out. These teeth are the main reason bolus look like they went through a blender.
 

Lorum

Arachnosquire
Joined
Jun 10, 2010
Messages
111
They are indeed called cheliceral teeth
Yes. They are different in form, size and number depending on the group of spiders who possess them, and they're of taxonomical significance. They can occur on the prolateral, retrolateral or both faces of the chelicerae.

I really thought everybody knew what they are and what they are for. It is a little strange, like if a scorpion keeper would not know that most scorpions have 8 eyes. No offense, it is honestly weird for me.
 
Last edited:

AphonopelmaTX

Moderator
Staff member
Joined
May 7, 2004
Messages
1,816
Yes. They are different in form, size and number depending on the group of spiders, and are of taxonomical significance. They can occur on the prolateral, retrolateral or both sides of the chelicerae.
Which taxa has chelicerae teeth on the pro and retrolateral faces? I've only known them to be on the dorsal side of the chelicera.

I really thought everybody knew what they are and what they are for. It is a little strange, like if a scorpion keeper would not know that most scorpions have 8 eyes. No offense, it is honestly weird for me.
Me too as a matter of fact.
 

Lorum

Arachnosquire
Joined
Jun 10, 2010
Messages
111
Which taxa has chelicerae teeth on the pro and retrolateral faces? I've only known them to be on the dorsal side of the chelicera
Sorry. My mistake. I meant, they can be on both margins of the cheliceral furrow. That is not pro- or retrolateral, but ventral in one side or the other of the cheliceral furrow (so, promargin or retromargin).

Having cheliceral teeth in both margins of the cheliceral furrow is a synapomorphy for Domiothelina, i.e. Idiopidae+[Ctenizidae+(Migidae+Actinopodidae)].
 
Top