A question about mosasaurs

[The Jersey Devil]

Hello everyone,

I just wanted to ask, is Mosasaurus maximus the same species as Mosasaurus hoffmani?

 

Thanks

[Fruitbat]

The original genus Mosasaurus is poorly-defined and is sometimes considered a 'catch-all' genus, so it all depends on who you listen to!  Most students of these beasties currently recognize M. maximus as a junior synonym of M. hoffmani. Unfortunately, one of the possibly most applicable articles to your question, T.L. Harrell and J.E. Martin (2015), is securely walled-off from general access by a pay-per-view ($35) wall.

 

-Joe

[piranha]

1 hour ago, Fruitbat said:

...Unfortunately, one of the possibly most applicable articles to your question, T.L. Harrell and J.E. Martin (2015), is securely walled-off from general access by a pay-per-view ($35) wall.

 

 

I have a copy, so it's not that secure!   Please send me a PM if you want a pdf. 

 

Harrell, T.L., & Martin, J.E. (2015)
A mosasaur from the Maastrichtian Fox Hills Formation of the northern Western Interior Seaway of the United States and the synonymy of Mosasaurus maximus with Mosasaurus hoffmanni (Reptilia: Mosasauridae).
Netherlands Journal of Geosciences, 94(1):23-37

 

[LordTrilobite]

I definitely wouldn't consider Mosasaurus hoffmanni a waste bin species. As far as I know M. maximus is indeed a junior synonym of M. hoffmanni.

 

It also wouldn't really be strange to have the same species over a very large area as they are sea going animals that can cover vast distances.

[abyssunder]

" Of the 13 species considered potentially valid at the beginning of this investigation, only three (M. hoffmannii, M. missouriensis, and M. lemonnieri ) were retained in the systematic revision of the genus, with a fourth new species M. glycys added. Two species, ‘M. gracilis’ and ‘M.‘ ivoensis were recognized to not be mosasaurines; three species (‘M. dekayi,’ ‘M. maximus,’ and ‘M. beaugei’ ) were determined to be junior synonyms of M. hoffmannii. The remaining five species (‘M. conodon, ‘M. mokoroa, ‘M. hobetsuensis, ‘M.’ flemingi, and 'M.’ prismaticus) have been reassigned to either existing or new genera in order to maintain the monophyly of the genus. " - as stated in H. P. Sreet. 2016. A re-assessment of the genus Mosasaurus (Squamata: Mosasauridae). A thesis submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy in Systematics and Evolution.

 

pdf document in my library (see below)

[Fruitbat]

Thanks pirahna and abyssunder...I should have said that the article is walled off from NORMAL people ...those of us who do not have access via an institutional account or deep pockets!  abyssunder has already given us the most salient quote for this discussion.

 

-Joe

[piranha]

1 hour ago, Fruitbat said:

...abyssunder has already given us the most salient quote for this discussion.

 

 

Sorry I didn't post the salient quote from Harrell & Martin.  I thought the offer of the paper you recommended would suffice!

 

Synonymy of Mosasaurus maximus with Mosasaurus hoffmanni

No distinguishing characteristic can be used to differentiate M. hoffmanni and M. maximus, supporting the synonomy of these two taxa (e.g. Mulder, 1999).  Although the arguments made by Mulder for synonymy were convincing, many of his morphological descriptions of M. hoffmanni versus M. maximus were lacking in detail.  The present examination of the morphology of M. hoffmanni and M. maximus provided no reasonable evidence to support their separate species designation.  Differences observed between individual specimens were minor and could be attributed to individual variation, ontogeny and / or diagenetic deformation.  The differences that were noted occurred in specimens on both sides of the Atlantic Ocean and were not endemic to one region.  M. maximus Cope, 1869 should be synonymized with M. hoffmanni Mantell, 1829 with the latter having senior priority.  This conclusion supports the suggestion of Mulder (1999).

 

[Fruitbat]

piranha...your offer of the paper was MORE than generous!  I was simply pointing out that the quote that abyssunder posted was sufficient to at least partially answer the original question in this topic.  As always, I greatly appreciate ALL of your invaluable contributions to The Fossil Forum!

 

-Joe

[piranha]

8 hours ago, Fruitbat said:

...I was simply pointing out that the quote that abyssunder posted was sufficient to at least partially answer the original question in this topic.

 

 

That quote was not an answer, only stating it was a synonym, without any explanation.  
Ironically, the paper you recommended has exactly the same info included in the title.  
The paper goes into great detail on this, so I was puzzled you didn't PM me for a pdf?
At least the excerpt I posted above provides an explanation why they are synonymous.

 

[abyssunder]

Question:
"...is Mosasaurus maximus the same species as Mosasaurus hoffmani ?
Answer:
 " Most students of these beasties currently recognize M. maximus as a junior synonym of M. hoffmani ."
"... three species ( ‘M. dekayi,’ ‘M. maximus,’ and ‘M. beaugei’ ) were determined to be junior synonyms of M. hoffmannii . "

 

The explanation was not requested.

[piranha]

42 minutes ago, abyssunder said:

...The explanation was not requested...

 

 

Seriously, are you are criticizing me for posting an unrequested explanation?
The answer was a simple 'yes', do you mean to imply that would be sufficient?  
Does that mean we should not provide a thorough and informative response? 
 
As you always post copious amounts of detailed info at TFF, I find this comment to be quite astounding!

 

[Fossildude19]

43 minutes ago, piranha said:

 

 

Seriously, are you are criticizing me for posting an unrequested explanation?
The answer was a simple 'yes', do you mean to imply that would be sufficient?  
Does that mean we should not provide a thorough and informative response? 
 
As you always post copious amounts of detailed info at TFF, I find this comment to be quite astounding!

 

 

Scott, 

I think Abyssunder was saying that Josephstrizhak asked the specific question "...is Mosasaurus maximus the same species as Mosasaurus hoffmani? ", and didn't request an explanation of why. 

 

Therefore, he only posted what he felt was relevant.  (Please keep in mind a language difference may be a factor here.) 

I don't think it was meant as a slight at you, Scott. Providing supporting data is always the best way to answer questions.  

 

As always, you went above and beyond, by  supplying not only the why to substantiate the answer, but also the more than generous offering of access to an interesting, ellusive (for some) and salient paper.  I can't believe anyone is faulting you for giving too good of an answer.  

 

Thank you, Scott, for not only your meaningful posting contributions - but for the generous spirit with which you share these papers with the Forum at large. 

 

 

 

 

 

[ynot]

1 hour ago, piranha said:

 

 

Seriously, are you are criticizing me for posting an unrequested explanation?
The answer was a simple 'yes', do you mean to imply that would be sufficient?  
Does that mean we should not provide a thorough and informative response? 
 
As you always post copious amounts of detailed info at TFF, I find this comment to be quite astounding!

 

Yeah, what Tim said!

for all Your efforts Sir!

[piranha]

26 minutes ago, Fossildude19 said:

I think Abyssunder was saying that Josephstrizhak asked the specific question "...is Mosasaurus maximus the same species as Mosasaurus hoffmani? ", and didn't request an explanation of why. 

 

Therefore, he only posted what he felt was relevant.  (Please keep in mind a language difference may be a factor here.) 

I don't think it was meant as a slight at you, Scott. Providing supporting data is always the best way to answer questions. 

 

 

This flawed logic does not pass the giggle test.  If that were true, simple 'yes' or 'no' answers would always suffice.  Discussions are dynamic because they are always evolving.  Extra information only adds to the dialogue, it never diminishes.  If someone pointed out each time he posted information or an explanation that was not requested, I imagine he would not be very pleased.  Considering the source of this comment, it strikes me as an unfair double-standard, to say the least. 

 

[abyssunder]

To answer your questions with the fewest possible words:
NO
NO
NO

With respect