Always Check For Trace Fossils .....

[Synechodus]

Already some time ago, I came across a peculiar deformation on the test of an Echinocorys gr. conoidea echinoid, that I had found in a local quarry. Intrigued, I showed this to the echinoid-specialist in the local Museum of Natural History in Maastricht, who has a fondness for ichnofossils.

And sure enough: he was intrigued too as he had never seen this type of trace fossil before.

To cut along story short: I donated this specimen to the museum and an article on this trace was written by two echinoid ichnofossil xperts who were kind enough to include my name.

Ichnology of Late Cretaceous echinoids from the Maastrichtian type area (The Netherlands, Belgium)－2. A pentagonal attachment scar on

Echinocorys gr. conoidea (Goldfuss)

Stephen K. Donovan*, John W. M. Jagt+, and Paul P. M. A. Dols#

Bulletin of the Mizunami Fossil Museum, no. 36 (2010), p. 51–53,

For me the next best thing to having one's name assigned to a new species....

Cheers,

Paul

pentagonal attachment scar.pdf

[Smaug]

Very cool, but maybe you should post the link to the PDF-file in your post on fossiel.net.

[Synechodus]

Very cool, but maybe you should post the link to the PDF-file in your post on fossiel.net.

Now there's the snag: it is not (yet) available on the internet and on fossiel.net I can't add attachments other than pictures ....

[earthdog]

It's great you donated your piece, and great that you got mention. Congratulations !

[Synechodus]

It's great you donated your piece, and great that you got mention. Congratulations !

Thanks, to me donating this specimen was a "nobrainer". It is far better of in a museum collection.

In the Netherlands relationships between the professional and amateur Paleontologists are by and large very good. The total amount of time that amateurs spend in the field is far bigger than those spent by the professionals and we amateurs know that if we find something "out of the ordinary" we should show it to the experts. A healthy and rewarding relationship for both parties.

Cheers,

Paul

[Guest Smilodon]

Thanks, to me donating this specimen was a "nobrainer". It is far better of in a museum collection.

In the Netherlands relationships between the professional and amateur Paleontologists are by and large very good. The total amount of time that amateurs spend in the field is far bigger than those spent by the professionals and we amateurs know that if we find something "out of the ordinary" we should show it to the experts. A healthy and rewarding relationship for both parties.

Cheers,

Paul

Good on you and good for you too!

[Harry Pristis]

What an interesting find, Paul!

In the paper, the name of the echinoid is presented as Echinocorys gr. conoidea (Goldfuss). I am not familiar with the use of "gr." -- what does it symbolize? Under what circumstances is it used?

It's common to see "Cf." (compare with) in taxonomic use, but I've not noticed "gr." till now.

[MikeD]

Very cool, Paul. Looking forward to more of your trip reports.

[Synechodus]

What an interesting find, Paul!

In the paper, the name of the echinoid is presented as Echinocorys gr. conoidea (Goldfuss). I am not familiar with the use of "gr." -- what does it symbolize? Under what circumstances is it used?

It's common to see "Cf." (compare with) in taxonomic use, but I've not noticed "gr." till now.

Hi Harry,

I was already wondering when someone was going to point this out .....

I will try to explain, but it won't be easy.

First of all, "gr." is short for "group" and reflects the fact that some palaeontologists prefer to treat certain test morphologies of Echinocorys as a sort of species group.

I could try to explain it more myself, but I don't think I could do better than what John Jagt, an expert on the Late Maastrichtian Echinoids around here, wrote on this topic in his thesis, entitled (Late Cretaceous-Early Palaeogene echinoderms and the K/T boundary in the southeast Netherlands and northeast Belgium Part 4: Echinoids):

START QUOTE

".........On various occasions, it has been shown in the literature that certain

test morphologies amongst representatives of the genus Echinocorys are typical of certain

stratigraphic levels (see e.g. Lambert, 1898, 1903; Ernst, 1970b, 1972, 1975a-b;

Fletcher, 1977; Wright & Smith, 1987; Wood, 1988). However, the occurrence of many

intermediates at all levels, including those typified by a certain test morphology, complicated

matters considerably. As a result of this, palaeontologists working with

species of Echinocorys have but two options, namely either lump all morphologies

into a single species, e.g. the type species E. scutata, a course of action favoured by Jeffery

(1997b) and Smith & Jeffery (in press), or alternatively, attempt to assign certain

test morphologies to previously described species, and treat these as a sort of species

group. The latter option is chosen here. The various types found in the Campanian

and lower Upper Maastrichtian strata in the Maastrichtian type area, are assigned to

species groups, to which the oldest available name is applied. It should be noted that

these groups are not afforded the status of full, biological species, but rather are

meant to illustrate the link between certain stratigraphic levels and peculiar test morphologies.

Apparently, various forms of Echinocorys are to be seen as distinct morphotypes

occurring at certain stratigraphic levels only, suggesting these to be ecophenotypes.

It is these types that can be used as index fossils, at least in a NW European setting.

Ernst ( 1970b, 1972, 1975a-B ) provided numerous illustrations of this. Despite

obvious drawbacks, it is this interpretation of the various types of Echinocorys that is

followed here, in part also because the alternative would obscure matters even more.

For example, to consider E. gr. conica and E. gr. subglobosa as a single species would

entirely mask their stratigraphic value, since these have been shown to be typical of

successive levels in the lower Upper Campanian of NW Europe.

The general description below applies to all representatives of the genus. For the

species groups recognised here, only selected synonyms and current data on geographic

distribution and stratigraphic range in the area are provided, the various

photographs illustrating typical examples of each species group........"

END QUOTE

I hope this craifies things a bit....

Cheers,

Paul

Edited February 26, 2010 by Synechodus

[Synechodus]

Very cool, Paul. Looking forward to more of your trip reports.

Will do. I have some nice pics and stories lined up. Just waiting for some more spare time .....

Cheers,

Paul

[MikeD]

Haha! If you find some extra spare time, please send it my way!

[MB]

Well done and congratulations

[Harry Pristis]

Hi Harry,

I was already wondering when someone was going to point this out .....

I will try to explain, but it won't be easy.

First of all, "gr." is short for "group" and reflects the fact that some palaeontologists prefer to treat certain test morphologies of Echinocorys as a sort of species group.

I could try to explain it more myself, but I don't think I could do better than what John Jagt, an expert on the Late Maastrichtian Echinoids around here, wrote on this topic in his thesis, entitled (Late Cretaceous-Early Palaeogene echinoderms and the K/T boundary in the southeast Netherlands and northeast Belgium — Part 4: Echinoids):

START QUOTE

".........On various occasions, it has been shown in the literature that certain

test morphologies amongst representatives of the genus Echinocorys are typical of certain

stratigraphic levels (see e.g. Lambert, 1898, 1903; Ernst, 1970b, 1972, 1975a-b;

Fletcher, 1977; Wright & Smith, 1987; Wood, 1988). However, the occurrence of many

intermediates at all levels, including those typified by a certain test morphology, complicated

matters considerably. As a result of this, palaeontologists working with

species of Echinocorys have but two options, namely either lump all morphologies

into a single species, e.g. the type species E. scutata, a course of action favoured by Jeffery

(1997b) and Smith & Jeffery (in press), or alternatively, attempt to assign certain

test morphologies to previously described species, and treat these as a sort of species

group. The latter option is chosen here. The various types found in the Campanian

and lower Upper Maastrichtian strata in the Maastrichtian type area, are assigned to

species groups, to which the oldest available name is applied. It should be noted that

these groups are not afforded the status of full, biological species, but rather are

meant to illustrate the link between certain stratigraphic levels and peculiar test morphologies.

Apparently, various forms of Echinocorys are to be seen as distinct morphotypes

occurring at certain stratigraphic levels only, suggesting these to be ecophenotypes.

It is these types that can be used as index fossils, at least in a NW European setting.

Ernst ( 1970b, 1972, 1975a-B ) provided numerous illustrations of this. Despite

obvious drawbacks, it is this interpretation of the various types of Echinocorys that is

followed here, in part also because the alternative would obscure matters even more.

For example, to consider E. gr. conica and E. gr. subglobosa as a single species would

entirely mask their stratigraphic value, since these have been shown to be typical of

successive levels in the lower Upper Campanian of NW Europe.

The general description below applies to all representatives of the genus. For the

species groups recognised here, only selected synonyms and current data on geographic

distribution and stratigraphic range in the area are provided, the various

photographs illustrating typical examples of each species group........"

END QUOTE

I hope this craifies things a bit....

Cheers,

Paul

Thank you, Paul; that does answer my question. It seems to be a compromise between "lumping" and "splitting." But, I don't understand the utility of it.

I am not an invertebrate collector, and don't keep up with taxonomic practices in that field. In vertebrate taxonomy, I think an ecophenotype might be designated as a subspecies (e.g. Lynx rufus koakudsi). I don't understand how a "group" might convey more biostratigraphic information than a subspecies.

As I think about it, I can't recall seeing subspecies used for inverts. Yet, it seems reasonable to expect some way to deal with ecophenotypes/morphotypes that are not distinct species. Is it that there are just too many Echinocorys morphotypes to manage without using this cluster system . . . that is, is this taxonomic shorthand?

Is this taxonomic group usage employed with genera other than Echinocorys ?

[Just Bob]

Very nice! Congratulations.

[Synechodus]

Thank you, Paul; that does answer my question. It seems to be a compromise between "lumping" and "splitting." But, I don't understand the utility of it.

I am not an invertebrate collector, and don't keep up with taxonomic practices in that field. In vertebrate taxonomy, I think an ecophenotype might be designated as a subspecies (e.g. Lynx rufus koakudsi). I don't understand how a "group" might convey more biostratigraphic information than a subspecies.

As I think about it, I can't recall seeing subspecies used for inverts. Yet, it seems reasonable to expect some way to deal with ecophenotypes/morphotypes that are not distinct species. Is it that there are just too many Echinocorys morphotypes to manage without using this cluster system . . . that is, is this taxonomic shorthand?

Is this taxonomic group usage employed with genera other than Echinocorys ?

Hi Harry,

It is indeed a basic compromise between "lumping" and "splitting".

The difficulty is obviously in defining when a difference in an echinoid test morphology is sufficient to warrant a completely new species, a subspecies or an ecophenotype/morphotype.

Remember: we humans came up with the taxonomic system and its rules in an attempt to bring order to the multitude of species we observe and not the other way around. It's not that one day an animal thinks "Hey why don't I give birth to a new subspecies today!"

Though I am certainly no expert on taxonomy: it seems to me that the use of "groups", subspecies and the likes are all ways of dealing with the variability within one species and preference for one or the other way may vary within a certain class of animals or even per person.

For example: instead of Echinocorys gr. conoidea I have also seen people using "Echinocorys scutata forma conoidea", which is basically also a compromise between lumping (Echinocorys scutata) and splitting (forma conoidea).

Cheers,

Paul

[Auspex]

It seems a good way to catalog observed differences while reflecting our degree of certainty about their meaning, and paving the way for future conclusions when the body of knowledge warrants.

[Harry Pristis]

Hi Harry,

It is indeed a basic compromise between "lumping" and "splitting".

The difficulty is obviously in defining when a difference in an echinoid test morphology is sufficient to warrant a completely new species, a subspecies or an ecophenotype/morphotype.

Remember: we humans came up with the taxonomic system and its rules in an attempt to bring order to the multitude of species we observe and not the other way around. It's not that one day an animal thinks "Hey why don't I give birth to a new subspecies today!"

Though I am certainly no expert on taxonomy: it seems to me that the use of "groups", subspecies and the likes are all ways of dealing with the variability within one species and preference for one or the other way may vary within a certain class of animals or even per person.

For example: instead of Echinocorys gr. conoidea I have also seen people using "Echinocorys scutata forma conoidea", which is basically also a compromise between lumping (Echinocorys scutata) and splitting (forma conoidea).

Cheers,

Paul

Thank you, Paul. Yes, certainly we are talking here, not about the vagaries of evolution, but about the mechanics and manipulations of the binomial system.

I have seen the "form" device used. I can see how "group" is useful as shorthand in situations where a precise identity of the Echinocorys is not important. For example, "The macrofauna of the site included Echinocorys (of the) group conoidea, thus confirming a Campanian-Lower Maastrichtian age for the exposure."

I can also see how liberating for taxonomists the "group" device might be -- a lot less labor over a microscope counting pores and taking measurements.

Thank you for your patient explications, Paul.

[Synechodus]

Thank you, Paul. Yes, certainly we are talking here, not about the vagaries of evolution, but about the mechanics and manipulations of the binomial system.

I have seen the "form" device used. I can see how "group" is useful as shorthand in situations where a precise identity of the Echinocorys is not important. For example, "The macrofauna of the site included Echinocorys (of the) group conoidea, thus confirming a Campanian-Lower Maastrichtian age for the exposure."

I can also see how liberating for taxonomists the "group" device might be -- a lot less labor over a microscope counting pores and taking measurements.

Thank you for your patient explications, Paul.

No thanks.

Inquiries like these help me to sharpen my own thinking

So, in a way, I should thank you as well.

Cheers,

Paul