siteseer Posted May 31, 2011 Share Posted May 31, 2011 (edited) I thought I would start a thread about an unusual shark species. I haven't seen anyone else write about it. Back in the 90's I knew a few collectors in New Zealand and traded fossils with them. From them I received a few rostral teeth of a sawshark genus (and species) I had not seen before. Sawsharks are true sharks (Order Pristiophoriformes). This distinguishes them from sawfishes, which are classified as rays. Today's sawsharks (Family Pristiophoridae) belong to the genera Pristiophorus (five species) and Pliotrema (one species). One other genus is known only as a fossil, Ikamauius, and only from sites in New Zealand ranging in age from Late Eocene to Early Pleistocene. There is only one named species, Ikamauius ensifer (name means "Maui's sword-bearing fish" - the author did not specify the Polynesian language in the etymology, possibly Maori). The rostral teeth of I. ensifer are very similar to those of Pliotrema but in Ikamauius the rostral teeth are barbed (serrated) on both the anterior and posterior edges. In Pliotrema they are barbed only on the posterior edge and only on longer specimens. The rostral teeth appear to be somewhat common at one locality (Campbell's Beach, Kakanui, Gee Greensand - age considered Late Oligocene to Early Miocene). When they are found, the root (peduncle) is usually missing so the specimens tend to be crowns broken somewhere toward the root. As far as I know, its oral teeth remain unknown but if the matrix breaks down, someone will likely find them in the 1-2mm size range. The pictured specimens are one well-preserved crown with part of the root (about 25mm long) and one apparent pathologic specimen (ripples in the enameloid). For more information: Keyes, I.W. 1979. Ikamauius, a new genus of fossil sawshark (Order Selachii: Family Pristiophoridae) from the Cenozoic of New Zealand. N.Z. Journal of Geology and Geophysics. Vol. 22(1): 125-129. Edited May 31, 2011 by siteseer 1 Link to comment Share on other sites More sharing options...
Northern Sharks Posted May 31, 2011 Share Posted May 31, 2011 Jess: This is a new one for me, thanks for the introduction and the great pic. For comparison, here is a Pliotrema from South Africa. 1 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...
jpc Posted May 31, 2011 Share Posted May 31, 2011 Cool fossil... cool story... excellent photo... thanks to share. Link to comment Share on other sites More sharing options...
alopias Posted May 31, 2011 Share Posted May 31, 2011 interesting teeth , Jess thanks for the comments ; Kevin other nice teeth in your collection Link to comment Share on other sites More sharing options...
Coco Posted May 31, 2011 Share Posted May 31, 2011 Today's sawsharks (Family Pristiophoridae) belong to the genera Pristiophorus (five species) and Pliotrema (one species). I know : Pristiophorus cirratus, P. japonicus, P. nudipinnis and P. schroederi. What is the last species ? It is a nice post, I think I never seen these species of teeth before. Thanks. Coco ---------------------- OUTIL POUR MESURER VOS FOSSILES : ici Ma bibliothèque PDF 1 (Poissons et sélaciens récents & fossiles) : ici Ma bibliothèque PDF 2 (Animaux vivants - sans poissons ni sélaciens) : ici Mâchoires sélaciennes récentes : ici Hétérodontiques et sélaciens : ici Oeufs sélaciens récents : ici Otolithes de poissons récents ! ici Un Greg... Link to comment Share on other sites More sharing options...
siteseer Posted May 31, 2011 Author Share Posted May 31, 2011 NS, That's a nice one. I have one as well (maybe we traded with a mutual friend). The ones I've seen have all come from Milnerton. Pliotrema is also known from a Mid-Late Paleocene of California. I've been to the site but didn't find anything. I heard you need to do a lot of screening. Jess Jess: This is a new one for me, thanks for the introduction and the great pic. For comparison, here is a Pliotrema from South Africa. Link to comment Share on other sites More sharing options...
siteseer Posted May 31, 2011 Author Share Posted May 31, 2011 Coco, A species was named in 2008, P. delicatus. I'd like to find that description. There is a mention of the species here: http://en.wikipedia.org/wiki/Sawshark Jess I know : Pristiophorus cirratus, P. japonicus, P. nudipinnis and P. schroederi. What is the last species ? It is a nice post, I think I never seen these species of teeth before. Thanks. Coco Link to comment Share on other sites More sharing options...
Coco Posted May 31, 2011 Share Posted May 31, 2011 Ah OK, I didn't know that. Thanks ! Coco ---------------------- OUTIL POUR MESURER VOS FOSSILES : ici Ma bibliothèque PDF 1 (Poissons et sélaciens récents & fossiles) : ici Ma bibliothèque PDF 2 (Animaux vivants - sans poissons ni sélaciens) : ici Mâchoires sélaciennes récentes : ici Hétérodontiques et sélaciens : ici Oeufs sélaciens récents : ici Otolithes de poissons récents ! ici Un Greg... Link to comment Share on other sites More sharing options...
xonenine Posted May 31, 2011 Share Posted May 31, 2011 (edited) here is a paper describing this (P.delicatus) and several other species...PDF Edited May 31, 2011 by xonenine "Your serpent of Egypt is bred now of your mud by the operation of your sun; so is your crocodile." Lepidus Link to comment Share on other sites More sharing options...
Roz Posted June 1, 2011 Share Posted June 1, 2011 What a beautiful tooth! So good to see one I have never seen before.. Welcome to the forum! Link to comment Share on other sites More sharing options...
sseth Posted June 1, 2011 Share Posted June 1, 2011 Those are incredible rostrum spines. I have never seen any quite like that. Seth _____________________________________ Seth www.fossilshack.com www.americanfossil.com www.fishdig.com Link to comment Share on other sites More sharing options...
fossilselachian Posted June 1, 2011 Share Posted June 1, 2011 Nice spines J-man. I think I've got a few also from NZ (have to check when I get home). However, they can't be as nice as the ones you have shown. Also, nice write-up on the subject. FS Link to comment Share on other sites More sharing options...
fossilselachian Posted June 6, 2011 Share Posted June 6, 2011 Nice spines J-man. I think I've got a few also from NZ (have to check when I get home). However, they can't be as nice as the ones you have shown. Also, nice write-up on the subject. FS Yes, I do indeed have a few - they came from YOU! Link to comment Share on other sites More sharing options...
sixgill pete Posted June 6, 2011 Share Posted June 6, 2011 Very good and interesting post siteseer ...... great looking rostrum and it is always great to learn of a species you have not heard of before 1 Bulldozers and dirt Bulldozers and dirt behind the trailer, my desert Them red clay piles are heaven on earth I get my rocks off, bulldozers and dirt Patterson Hood; Drive-By Truckers May 2016 May 2012 Aug 2013, May 2016, Apr 2020 Oct 2022 Link to comment Share on other sites More sharing options...
Dave pom Allen Posted June 6, 2011 Share Posted June 6, 2011 (edited) I have found these spikes before here in New Zealand and was always of the opinion that they were fish dorsal spines as they have been found in association with fish vertebrate inside concretions so always thought them to be fish. tangahoe formation pliocene - late miocene, 2 locations taranaki nz. Edited June 6, 2011 by Dave pom Allen 2 Link to comment Share on other sites More sharing options...
siteseer Posted June 7, 2011 Author Share Posted June 7, 2011 You would have to read the description by Keyes (1979). He did a histological study and concluded they were sawshark spines. I have found these spikes before here in New Zealand and was always of the opinion that they were fish dorsal spines as they have been found in association with fish vertebrate inside concretions so always thought them to be fish. tangahoe formation pliocene - late miocene, 2 locations taranaki nz. 1 Link to comment Share on other sites More sharing options...
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