Northern Sharks Posted November 19, 2010 Share Posted November 19, 2010 Since I just purchased a nice I.desori from Bakersfield, can any of you local collectors give me an idea as to how common they are compared to I.hastalis or I.planus. Elasmo says they are relatively uncommon, but does that mean 1 for every 20 planus, every 50, more? Also, I've seen one dealer say there's a very narrow form of I. hastalis from Bakersfield as well. Any truth to this, or is it just desori+hype? I'll post a pic of the tooth in my gallery this weekend. Thanks in advance There's no limit to what you can accomplish when you're supposed to be doing something else Link to comment Share on other sites More sharing options...
isurus90064 Posted November 19, 2010 Share Posted November 19, 2010 Already in the Middle Miocene dental characteristics (tooth function) for desori are decidedly different if compared to hastalis. The "narrow" form of hastalis seems to generally occur in relatively smaller teeth and could very well be a ontogenetic tooth character rather than evidence of yet another shark at STH. Also if it weren't ontogeny, then it would still seem like it would fit within the morphological 'range' of hastalis. Btw, this narrrow/wide variation is not the same juxtaposition you see in Lee Creek Isurus (Cosmopolitodus). As far as # of true desori teeth, that too is a little hard to say without having access to collections that have no or little collecting bias. I do think it is safe to say though that for each desori you will have to find dozens if not more of planus and hastalis. 1 Fossil shark teeth from all over: http://www.thefossilforum.com/index.php?/topic/2380-extraordinary-common-teeth/ Link to comment Share on other sites More sharing options...
siteseer Posted November 20, 2010 Share Posted November 20, 2010 Northern Sharks, I can tell you that one day I found 49 hastalis, 24 planus and 5 oxyrinchus. On another day I found 43 hastalis, 24 planus, and 5 oxyrinchus. There was also a day when I found 57 hastalis, 30 planus, and no oxyrinchus. I pick up every tooth that is more than 50% complete because I have been interested in narrowing down the rarity/abundance of the STH animals for a while. Yeah, some dealers try to push a not-so-odd variation as a different species. As noted by isurus90064, there appears to be only one form of STH hastalis and you can find juveniles to adults. Jess Since I just purchased a nice I.desori from Bakersfield, can any of you local collectors give me an idea as to how common they are compared to I.hastalis or I.planus. Elasmo says they are relatively uncommon, but does that mean 1 for every 20 planus, every 50, more? Also, I've seen one dealer say there's a very narrow form of I. hastalis from Bakersfield as well. Any truth to this, or is it just desori+hype? I'll post a pic of the tooth in my gallery this weekend. Thanks in advance Link to comment Share on other sites More sharing options...
isurus90064 Posted November 22, 2010 Share Posted November 22, 2010 Nice to have some solid stats from siteseer. I did something similar and need to find my notebook on that. To add one other comment, the 4th Isurus that occurs at STH as well is retroflexus. This is the rarest of Isurus from here. Fossil shark teeth from all over: http://www.thefossilforum.com/index.php?/topic/2380-extraordinary-common-teeth/ Link to comment Share on other sites More sharing options...
FossilForKids Posted November 22, 2010 Share Posted November 22, 2010 There was a spot on the back side of hanglider where I was finding them at about a 1 per every 5 planus. John If only my teeth are so prized a million years from now! Link to comment Share on other sites More sharing options...
Northern Sharks Posted November 22, 2010 Author Share Posted November 22, 2010 Thanks for the input guys. Here's the tooth There's no limit to what you can accomplish when you're supposed to be doing something else Link to comment Share on other sites More sharing options...
FossilForKids Posted November 22, 2010 Share Posted November 22, 2010 That's a very nice speciman. Because of their smallish size I use to give them away during my Kids programs. Here's a nice little guy. John If only my teeth are so prized a million years from now! Link to comment Share on other sites More sharing options...
isurus90064 Posted November 23, 2010 Share Posted November 23, 2010 Both very nice examples! Fossil shark teeth from all over: http://www.thefossilforum.com/index.php?/topic/2380-extraordinary-common-teeth/ Link to comment Share on other sites More sharing options...
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