#MolluscMonday Sectioned Kosmoclymenia undulata from the Late Devonian, the position of the siphuncle labelled. In ammonoids of the order Clymeniida the siphuncle, a tube allowing access to the inner shell chambers, is located on the inside of the spiral (cf. ammonites where it is on the outside).
January 26, 2026 at 8:01 AM
#MolluscMonday Sectioned Kosmoclymenia undulata from the Late Devonian, the position of the siphuncle labelled. In ammonoids of the order Clymeniida the siphuncle, a tube allowing access to the inner shell chambers, is located on the inside of the spiral (cf. ammonites where it is on the outside).
#MolluscMonday This sectioned nautiloid shows the siphuncle bisecting the chambers. Cenoceras pseudolineatus from the Middle Jurassic of Dorset, England.
March 16, 2026 at 7:24 AM
#MolluscMonday This sectioned nautiloid shows the siphuncle bisecting the chambers. Cenoceras pseudolineatus from the Middle Jurassic of Dorset, England.
Nature research paper: Earliest siphuncle-bearing cephalopod from the early Cambrian
go.nature.com/3RIQsNQ
go.nature.com/3RIQsNQ
Earliest siphuncle-bearing cephalopod from the early Cambrian - Nature
Early Cambrian Eoceras shaanxiense gen. et sp. nov. preserves septa and a segmented tube resembling a primordial siphuncle, extending cephalopod origins and revealing early assembly of chambered shells used for buoyancy regulation.
go.nature.com
August 4, 2026 at 10:32 AM
Nature research paper: Earliest siphuncle-bearing cephalopod from the early Cambrian
go.nature.com/3RIQsNQ
go.nature.com/3RIQsNQ
Song, Z., Pan, B., Guo, J. et al. Earliest siphuncle-bearing cephalopod from the early Cambrian. Nature (2026). doi.org/10.1038/s415...
Earliest siphuncle-bearing cephalopod from the early Cambrian - Nature
Early Cambrian Eoceras shaanxiense gen. et sp. nov. preserves septa and a segmented tube resembling a primordial siphuncle, extending cephalopod origins and revealing early assembly of chambered shell...
doi.org
July 29, 2026 at 6:42 PM
Song, Z., Pan, B., Guo, J. et al. Earliest siphuncle-bearing cephalopod from the early Cambrian. Nature (2026). doi.org/10.1038/s415...
Happy #MolluscMonday
Check out this beautiful broken #Nautilus revealing the internal chambers, septa and the #siphuncle . There are some cool boring? traces as well
#Cephalopoda
#molluscsofsrilanka
Check out this beautiful broken #Nautilus revealing the internal chambers, septa and the #siphuncle . There are some cool boring? traces as well
#Cephalopoda
#molluscsofsrilanka
November 25, 2024 at 3:55 AM
Happy #MolluscMonday
Check out this beautiful broken #Nautilus revealing the internal chambers, septa and the #siphuncle . There are some cool boring? traces as well
#Cephalopoda
#molluscsofsrilanka
Check out this beautiful broken #Nautilus revealing the internal chambers, septa and the #siphuncle . There are some cool boring? traces as well
#Cephalopoda
#molluscsofsrilanka
I'm deep into retirement, so most of my #FossilFriday posts will be unapologetically retrospective. This is a field shot from 2015. It's the siphuncle of a BIG late Ordovician (~445 MYA) actinocerid cephalopod mollusc ... yes, that's our helicopter skid for scale. Churchill R., n. Manitoba, CANADA
January 24, 2025 at 3:12 PM
I'm deep into retirement, so most of my #FossilFriday posts will be unapologetically retrospective. This is a field shot from 2015. It's the siphuncle of a BIG late Ordovician (~445 MYA) actinocerid cephalopod mollusc ... yes, that's our helicopter skid for scale. Churchill R., n. Manitoba, CANADA
An Orthoconic nautiloid fossil (wet and dry).
"The curved septae separating the chambers are distinctive and the blobs in the centre are parts of deposits along the central siphuncle which is what connects all the chambers." Thanks to @burrengeopark for the ID and info.
County Donegal, Ireland.
"The curved septae separating the chambers are distinctive and the blobs in the centre are parts of deposits along the central siphuncle which is what connects all the chambers." Thanks to @burrengeopark for the ID and info.
County Donegal, Ireland.
August 30, 2025 at 9:44 AM
An Orthoconic nautiloid fossil (wet and dry).
"The curved septae separating the chambers are distinctive and the blobs in the centre are parts of deposits along the central siphuncle which is what connects all the chambers." Thanks to @burrengeopark for the ID and info.
County Donegal, Ireland.
"The curved septae separating the chambers are distinctive and the blobs in the centre are parts of deposits along the central siphuncle which is what connects all the chambers." Thanks to @burrengeopark for the ID and info.
County Donegal, Ireland.
Earliest siphuncle-bearing cephalopod from the early Cambrian🧪
www.nature.com/articles/s41...
Collectively, these features identify the segmented tube in E. shaanxiense as a candidate primordial cephalopod siphuncle, extending known range of stem cephalopods back to early Cambrian.
www.nature.com/articles/s41...
Collectively, these features identify the segmented tube in E. shaanxiense as a candidate primordial cephalopod siphuncle, extending known range of stem cephalopods back to early Cambrian.
August 11, 2026 at 2:00 PM
Earliest siphuncle-bearing cephalopod from the early Cambrian🧪
www.nature.com/articles/s41...
Collectively, these features identify the segmented tube in E. shaanxiense as a candidate primordial cephalopod siphuncle, extending known range of stem cephalopods back to early Cambrian.
www.nature.com/articles/s41...
Collectively, these features identify the segmented tube in E. shaanxiense as a candidate primordial cephalopod siphuncle, extending known range of stem cephalopods back to early Cambrian.
Happy #MolluscMonday
Check out this beautiful broken #Nautilus revealing the.internal chambers, septa and the #siphuncle . There are some cool boring? traces as well
#Cephalopoda
#mollucsofsrilanka
Check out this beautiful broken #Nautilus revealing the.internal chambers, septa and the #siphuncle . There are some cool boring? traces as well
#Cephalopoda
#mollucsofsrilanka
February 26, 2024 at 4:45 AM
Happy #MolluscMonday
Check out this beautiful broken #Nautilus revealing the.internal chambers, septa and the #siphuncle . There are some cool boring? traces as well
#Cephalopoda
#mollucsofsrilanka
Check out this beautiful broken #Nautilus revealing the.internal chambers, septa and the #siphuncle . There are some cool boring? traces as well
#Cephalopoda
#mollucsofsrilanka
Love that Stockholm floors are often paved by these orthocone limestones some of which are huge!
And is that a trilobite I see before me?! ⚒️🧪
#pavementgeology
And is that a trilobite I see before me?! ⚒️🧪
#pavementgeology
April 30, 2025 at 1:16 PM
Love that Stockholm floors are often paved by these orthocone limestones some of which are huge!
And is that a trilobite I see before me?! ⚒️🧪
#pavementgeology
And is that a trilobite I see before me?! ⚒️🧪
#pavementgeology
Great Uncle Siphuncle: Eoceras, a small shelly fossil, is the earliest siphuncle-bearing cephalopod. Paper in @nature.com www.nature.com/articles/s41...
Earliest siphuncle-bearing cephalopod from the early Cambrian - Nature
Early Cambrian Eoceras shaanxiense gen. et sp. nov. preserves septa and a segmented tube resembling a primordial siphuncle, extending cephalopod origins and revealing early assembly of chambered shell...
www.nature.com
July 29, 2026 at 4:01 PM
Great Uncle Siphuncle: Eoceras, a small shelly fossil, is the earliest siphuncle-bearing cephalopod. Paper in @nature.com www.nature.com/articles/s41...
WOW. forgot I had this! Lovely prep of the inside of a Nautilus shell showing siphuncle and the chambers within! #molluscmonday 2017 Melbourne
September 12, 2025 at 3:56 PM
WOW. forgot I had this! Lovely prep of the inside of a Nautilus shell showing siphuncle and the chambers within! #molluscmonday 2017 Melbourne
A look at the chambers inside of a Nautilus shell and some siphuncle talk from Dr. Beaman. That's a fun word. I absolutely spelled it wrong on the 1st try. Google said "did you mean sigh uncle". No I did not 🙄 @schmidtocean.bsky.social dive 392 part B #ozoceans2020 #visioningcoralsea #MarineLife
March 26, 2026 at 10:25 PM
A look at the chambers inside of a Nautilus shell and some siphuncle talk from Dr. Beaman. That's a fun word. I absolutely spelled it wrong on the 1st try. Google said "did you mean sigh uncle". No I did not 🙄 @schmidtocean.bsky.social dive 392 part B #ozoceans2020 #visioningcoralsea #MarineLife
It's not much, but here's the ammonite impression that was found with this specimen. As far as Niobrara ammonites go, it's pretty nice since the aragonite shells never preserve.
April 6, 2026 at 4:30 PM
It's not much, but here's the ammonite impression that was found with this specimen. As far as Niobrara ammonites go, it's pretty nice since the aragonite shells never preserve.
Everything she swore, she wouldn't do. Lying ass siphuncle
February 6, 2025 at 9:38 PM
Everything she swore, she wouldn't do. Lying ass siphuncle
Apparently, there is a new early #cambrian #cephalopod. I am still sceptical, because this has been claimed many times before and always turned out to be something else ...
https://www.nature.com/articles/s41586-026-10868-y
#Palaeontology #science #nature
https://www.nature.com/articles/s41586-026-10868-y
#Palaeontology #science #nature
Earliest siphuncle-bearing cephalopod from the early Cambrian - Nature
Early Cambrian Eoceras shaanxiense gen. et sp. nov. preserves septa and a segmented tube resembling a primordial siphuncle, extending cephalopod origins and revealing early assembly of chambered shells used for buoyancy regulation.
www.nature.com
July 29, 2026 at 6:05 PM
Apparently, there is a new early #cambrian #cephalopod. I am still sceptical, because this has been claimed many times before and always turned out to be something else ...
https://www.nature.com/articles/s41586-026-10868-y
#Palaeontology #science #nature
https://www.nature.com/articles/s41586-026-10868-y
#Palaeontology #science #nature
#MolluskMonday represents today with Nautilus, a modern chambered cephalopod. Like ammonites, nautiloids have an external conch and lived in the final chamber, using the camerae for floatation. However, ammonites were much more closely related to coleoids like Spirula, with its intenal conch. ⚒️🧪
February 16, 2026 at 10:35 PM
#MolluskMonday represents today with Nautilus, a modern chambered cephalopod. Like ammonites, nautiloids have an external conch and lived in the final chamber, using the camerae for floatation. However, ammonites were much more closely related to coleoids like Spirula, with its intenal conch. ⚒️🧪
Siphuncle
#MolluscMonday Sectioned Kosmoclymenia undulata from the Late Devonian, the position of the siphuncle labelled. In ammonoids of the order Clymeniida the siphuncle, a tube allowing access to the inner shell chambers, is located on the inside of the spiral (cf. ammonites where it is on the outside).
February 2, 2026 at 3:38 PM
Siphuncle
The internal shell of Spirula is really something else!
I remember seeing this video for the first time and being gobsmacked by the little booger doing an underwater headstand, essentially balancing on the buoyant phragmocone hidden opposite the arms. 🦑🧪
I remember seeing this video for the first time and being gobsmacked by the little booger doing an underwater headstand, essentially balancing on the buoyant phragmocone hidden opposite the arms. 🦑🧪
January 31, 2026 at 6:05 AM
The internal shell of Spirula is really something else!
I remember seeing this video for the first time and being gobsmacked by the little booger doing an underwater headstand, essentially balancing on the buoyant phragmocone hidden opposite the arms. 🦑🧪
I remember seeing this video for the first time and being gobsmacked by the little booger doing an underwater headstand, essentially balancing on the buoyant phragmocone hidden opposite the arms. 🦑🧪
This #FossilFriday, another beautiful #Newfoundland fossil: an orthocerid nautiloid from #Ordovician rocks in western Newfoundland. It's a great teaching specimen, as it shows both the internal chamber walls (septae) and the central air/water canal (siphuncle).
Photos: Chris Brown
Photos: Chris Brown
December 19, 2025 at 1:51 PM
This #FossilFriday, another beautiful #Newfoundland fossil: an orthocerid nautiloid from #Ordovician rocks in western Newfoundland. It's a great teaching specimen, as it shows both the internal chamber walls (septae) and the central air/water canal (siphuncle).
Photos: Chris Brown
Photos: Chris Brown
Niphi Kaloku Siphuncle Age? by Mfezeko Gumada interview in C-A-K-E
mixed media motivated by the dung beetle, of all creatures “My work interprets what a dung beetle does... read more link in bio.
#art #contemporaryart #modernart #journalist #interview #editorial #artconsultant #artist #mixedmedia
mixed media motivated by the dung beetle, of all creatures “My work interprets what a dung beetle does... read more link in bio.
#art #contemporaryart #modernart #journalist #interview #editorial #artconsultant #artist #mixedmedia
March 25, 2025 at 8:13 AM
Niphi Kaloku Siphuncle Age? by Mfezeko Gumada interview in C-A-K-E
mixed media motivated by the dung beetle, of all creatures “My work interprets what a dung beetle does... read more link in bio.
#art #contemporaryart #modernart #journalist #interview #editorial #artconsultant #artist #mixedmedia
mixed media motivated by the dung beetle, of all creatures “My work interprets what a dung beetle does... read more link in bio.
#art #contemporaryart #modernart #journalist #interview #editorial #artconsultant #artist #mixedmedia
Also got some lovely carboniferous #Crinoids #bryozoans and orthocone #Nautiloids too. #geology #paleontology #fossilfriday
July 17, 2026 at 4:27 PM
Also got some lovely carboniferous #Crinoids #bryozoans and orthocone #Nautiloids too. #geology #paleontology #fossilfriday
More invertebrate fossils found this summer:
The very smol-est orthocone cephalopod from the Ordovician Juab Formation of western Utah. If you look close you can see the chambers are variably filled with calcite cement and carbonate mud. You can also see the siphuncle toward the narrow end. ⚒️
The very smol-est orthocone cephalopod from the Ordovician Juab Formation of western Utah. If you look close you can see the chambers are variably filled with calcite cement and carbonate mud. You can also see the siphuncle toward the narrow end. ⚒️
August 8, 2023 at 2:40 PM
More invertebrate fossils found this summer:
The very smol-est orthocone cephalopod from the Ordovician Juab Formation of western Utah. If you look close you can see the chambers are variably filled with calcite cement and carbonate mud. You can also see the siphuncle toward the narrow end. ⚒️
The very smol-est orthocone cephalopod from the Ordovician Juab Formation of western Utah. If you look close you can see the chambers are variably filled with calcite cement and carbonate mud. You can also see the siphuncle toward the narrow end. ⚒️
Nautiloids can be distinguished from ammonites by their simple septa and a siphuncle running through the center rather than the outer margin. While ammonites might have survived the Chicxulub impact and persisted briefly into the Cenozoic, nautiloids made it to the present day. True survivors! ☄️
January 5, 2026 at 10:44 PM
Nautiloids can be distinguished from ammonites by their simple septa and a siphuncle running through the center rather than the outer margin. While ammonites might have survived the Chicxulub impact and persisted briefly into the Cenozoic, nautiloids made it to the present day. True survivors! ☄️