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Post by brunni on May 24, 2011 20:10:00 GMT
Around mount Cameroon there is a large indigenous population of various Achatinidae species. With so much "meat on the hoof" roaming around, it is not surprising that a predator situation develops. There are birds, animals, reptiles, humans.............and other snails preying on these herbivorous snails. The family Streptaxidae is widespread throughout the region. A family of snails preying on others of their kind. They are minute to small in size; shells are white and translucent so that the color of the inhabitant animal colors the whole shell. Lime green is a popular color for these predators ( camouflage in the grass ? ). The largest species in this family would probably be Edentulina affinis Boettger, 1913, up to 30mm, rather broad in shape. Internet images are to be found. POLYPED ( forum member) obtained a slightly smaller Streptaxidae sp. from the area with a lime-green animal. I was fortunate to receive some specimens from him recently which are illustrated in attachment. Would any member have a name for this carnivore/cannibal ? Attachments:
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coyote
Archachatina papyracea
Cochleas ego amo
Posts: 2,955
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Post by coyote on May 24, 2011 20:30:46 GMT
I agree that their color is probably a very good camouflage. Those are really beautiful snails!  |
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Post by brunni on May 25, 2011 6:36:47 GMT
Here's another image of the Edentulina sp. s-t-r-e-t-c-h-i-n-g. The animals are amazing flexible and "elastic". Perhaps this helps them in hunting and killing other snails ? Attachments:
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Post by wolf on May 25, 2011 16:56:46 GMT
Hi, brunni,
"Would any member have a name for this carnivore/cannibal ?"
Sorry, me not....... . I´m lookin´ for an intact empty specimen. Then I should scan the new, old and very old literature. Hell of a job........ .
Can we be sure about the origin ("Mount Cameroon")? It´s extremely helpful to know the exact place of origin.
Kind regards: wolf
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coyote
Archachatina papyracea
Cochleas ego amo
Posts: 2,955
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Post by coyote on May 25, 2011 22:37:08 GMT
Here's another image of the Edentulina sp. s-t-r-e-t-c-h-i-n-g. The animals are amazing flexible and "elastic". Perhaps this helps them in hunting and killing other snails ? I've found that many of the carnivorous snails are long and thin, to reach inside other snail shells far enough to find something to eat. |
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Post by polyped on May 26, 2011 13:51:14 GMT
...... Can we be sure about the origin ("Mount Cameroon")? It´s extremely helpful to know the exact place of origin.Kind regards: wolf yes! the orgin is MBONGE, C U Peter |
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Post by wolf on May 26, 2011 17:37:02 GMT
Thank you, Peter, for the details! Good to know........ . "Danke"....... : wolf |
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Post by brunni on May 27, 2011 7:36:41 GMT
Length of the shell is around 21 - 23 mm and it is probably not too uncommon in the area where it is found.
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Post by wolf on May 27, 2011 7:58:45 GMT
Thanks, brunni! The more we know, the better....... . Kind regards: wolf |
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Post by brunni on May 27, 2011 14:31:03 GMT
.. . I´m lookin´ for an intact empty specimen. ------------------------------------------------------------------- Hi Wolf...............where are you looking  ?......you got this species alive? ........or me & POLYPED should look to see what we can find to send you ::)javascript:add("%20: ") |
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Post by wolf on May 27, 2011 14:59:11 GMT
I never held a specimen of this species in my hands  , so far, I´ve only seen some pictures in the www......... . Nevertheless, I´m very interested to find out the name, just for fun....... . Got a PN. Kind regards: wolf |
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Post by brunni on May 30, 2011 17:24:11 GMT
Hi Wolf Specimens are on their way to you so you can give us a feedback in due course. Meantime I'm posting an image of the "big brother" of this cannibal snail which is also found in the same region : Edentulina affinis Boettger, 1913. Naturally it also feeds on Achatina. This shell is 41.2mm ( more than double the length of the Edentulina sp. ) and it has been found at the base of mount Cameroon. It would be interesting to see the animal of E. affinis to see if it resembles the smaller species. I do not know if images or a description of the live animal are available ? Attachments:
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Post by wolf on May 30, 2011 17:59:29 GMT
Juhuuuu, brunni, thanks a lot . See PN....... . " I do not know if images or a description of the live animal are available ?" I´ll have a look. Kind regards: wolf |
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Post by brunni on May 31, 2011 6:20:54 GMT
Well Wolf I think you are going to have a tough job.
I looked in a book last night ( Compendium of Landsnails R. TUCKER ABBOT, 1989 ) and found an image of Eustreptaxis monrovius (Rang, 1831), 3cms from Liberia. Listed as synonyms are E. nobilis Gray, 1837 and E. rimatus Pfeiffer, 1847. This species looks pretty close to E. affinis Boettger, 1913 though it is smaller. The image is of the shell and not of the animal.
Good luck ! Brunni
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Post by wolf on May 31, 2011 17:49:24 GMT
brunni wrote: " you are going to have a tough job". True enough........  . Might take some time, too. Japs, one should look for one or another close related genus, too. We´ll see......... . Regards: wolf |
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Post by brunni on Jun 1, 2011 6:36:31 GMT
Hey Wolf !
Been reading up some more on African Streptaxidae, this time in "Tropical Landsnails of the world" by Parkinson, Hemmen & Groh, 1987.............and bingo ! ..........There is an image of Gonaxis kibweziensis (E.A. Smith, 1894) described from Kenya : the animal is a custard yellow with the extremities tending to orange-brown ( quite a contrast in color to the lime green of the Cameroon sp.) But the shell, also around 22mm, translucent white with delicate ribbing, in fact pretty similar to some of the shells mentioned in my previous messages.
I would like to scan and paste the image of this beautiful animal but I will infringe copyright regulations.
So as you say, species of this family living African have a number of similar looking shells, but assigned to different genera.
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Post by wolf on Jun 1, 2011 15:28:39 GMT
brunni: Thanks......... . I´ve just seen Gonaxis kibweziensis in my Parkinson, Hemmen & Groh, p. 154. Yes, the shell is pretty close to some Edentulina species. A lot of work has to be done, I suppose....... . Regards: wolf
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Post by brunni on Jun 1, 2011 17:32:06 GMT
o.k. Wolf, good we got same books. Did you see pic of live animal on p. 34 ? Very pretty. I think most forum readers know that Achatina fulica has been spread world-wide in tropical areas through the intervention of humans, where is remains an agricultural pest and competitor with with indigenous herbivorous snails for food. To "rectify" the situation, humans then introduced some of these native African cannibal species ( e.g. Gonaxis kibwenziensis from Kenya ) to some areas (e.g. Indo-Australian region ) to hunt down the aberrant fulicas and bring them under control. Trouble is it did not quite work like that. These cannibals instead preyed on the natural local species.........and the fulicas continued with their invasion !  |
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Post by wolf on Jun 1, 2011 19:54:33 GMT
"Did you see pic of live animal on p. 34 ?" Japs. Beautiful........ .
Now I´ve learned, that not only Euglandina was introduced to reduce Achatina fulica populations (without any effect on this species), but also Gonaxis. Thanks for pointing that out.
Sincerely yours: wolf
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Post by brunni on Jun 6, 2011 14:14:26 GMT
Good to hear the specimens reached you Wolf !
We discussed now so many genera of African Streptaxidae :
Edentulina
Euglandina
Eustreptaxis
Gonaxis...........................you are going to have a lot of head scratching sorting them out.
Good luck ( you're going to need it ) - Brunni
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Post by wolf on Jun 6, 2011 19:00:28 GMT
Hi Brunni, thanks again for the two specimens. Beautiful and mysterious. That makes me glad and busy ;D........... . On the other hand: hell of a job. True enough, it may take some time to solve the problem. First of all, I will have to enlarge my library . Some papers I need have 300 pages and more, ups, and they are not available via internet, obviously. Thank you for your help, kind regards: wolf |
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Post by brunni on Jun 9, 2011 15:38:21 GMT
I am wondering if any Forum members can help us out here. It concerns the coloring of the living animals of Streptaxidae species. This tab started off with :
Edentulina sp. ex Mbonge, Mene division, south-west Cameroon : animal YELLOW-GREEN with distinct BLACKISH micordots along the dorsal exposed portion.
We then noted :
Gonaxis kibweziensis (E.A. Smith, 1894) described from Kenya : animal CUSTARD YELLOW with the extremities tending to ORANGE-BROWNustard yellow with the extremities tending to orange-brown
Now I red about another Streptaxidae from the Island of Mauritius : Gonidomus pagoda (Ferrusac) and the animal is BRIGHT RED.
It seems that animals of this family are amongst the most colorful around !
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coyote
Archachatina papyracea
Cochleas ego amo
Posts: 2,955
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Post by coyote on Jun 9, 2011 19:15:14 GMT
I have never even heard of those species before. I hope there are others who can respond better to this while i go off to google these snails.
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Post by brunni on Oct 27, 2011 12:27:05 GMT
@ Wolf  Did you get anywhere to identify these little green cannibals ? |
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Post by wolf on Oct 27, 2011 18:06:04 GMT
Hi, brunni! Not yet......... Unfortunately I'm involved in a project analyzing nearly 30 thousand specimens (besides my normal work, of course). So since several weeks my nights are short . But I'll keep the "cannibals in mind"....... . Kind regards: wolf |
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?......you got this species alive?
, so far, I´ve only seen some pictures in the www......... .
. Might take some time, too. 
