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Re: New in CJES
Aren't haramiyid postcanines supposed to look more or less like this?
Er... Trevor? :-]
Reply to David M:
I repeat the entire text because many people probably didn't get it -- it
was in HTML, and the version that I got via the list is "plain" text without
I only read papers, and don't claim to understand the words! 'Haramiyid'
postcanines are something like elongated bowls surrounded by cusps. A
'dentine-lacking posterior shelf' isn't something I've heard of.
Neither have I. That is clearly odd.
As it happens, I do have a couple of paragraphs which might contain
something or other. The first is my breif, generalised overview of
'haramiyids'. I think I'll add the sources as one block below.
"The general picture (by Self, MY ie. me!)
Kemp, 2005 (p.140-141) provides a concise overview of the postcanines.
Harami molars are larger than many of their equivalents from contemporary
mammals, but not by much. These are blessed with lots of cusps and are
The crowns are wide and have a line of three large cusps on one edge, with
five smaller ones on the opposing side. As there's a connecting ridge at
one end and a basin in between, the general idea is a crater surrounded by
a number of hills.
Originally, it was thought that upper and lower molars were pretty much
mirror images of each other, and minor details lead to the establishment
of two genera: /Thomasia/ and /Haramiya/. The suggestion was subsequently
made that these could also represent uppers and lowers of only one genus,
and the discovery of /Haramiyavia/ provided confirmation for that."
(The word order could be confusing. /T./ contributed the lowers and /H./
the uppers. I'd better do a quick edit to the directory.)
(And the "best" thing is that *T.* has priority...)
A slightly more intimate account of a lower molar is provided by
/Eleutherodon oxfordensis/ from the Middle Jurassic of southern England.
These notes are based on the paper by Butler & Hooker.
A pair of the new specimens are incomplete lowers. A Dorset one, BMNH
46851, spent some time rolling around after the death of the owner. This
playful behaviour was presumably at the behest of moving water, and it
cost most of its enamel. However, the decorative fluting in the basin is
preserved and wear was light during life. Seen from the occlusal
perspective, the crown is a longish oval with maximum measurements of 2.2
and 1.55mm, (length and width respectively, p.189). The highest cusp is on
a prominence at the front. This is termed b2. A line of (probably) six
cusps runs along a ridge on the buccal side, and there are traces of a
broadly similar number on the lingual aspect. Both lines carried on until
the back of the tooth. The central basin was surrounded."
Sources and so on
Dykes TD aka Self MY (amateur webpage): 'Haramiyida' - an internet
Butler PM & Hooker JJ (2005), New teeth of allotherian mammals from the
English Bathonian, including the earliest multituberculates, Acta
Palaeontologica Polonica, 50(2), p.185-207.
Kemp TS (2005), The Origin and Evolution of Mammals, Oxford University