We must show some inside detail if we want our marine shells identified. The outside shapes, colours and textures are often lovely but will not always lead to a definitive ID.
Venerupis corrugata The Pullet has the perfect shell for internal features. It is rare to find one where the internal architecture is not on view - picture 2. One might have to turn it in the light a little to show the lines.
Like all shells it is probably best to take it to a base and examine it under good lighting but it is not difficult to ID in the field by shape alone - pictures 3 & 4.
Compared to other common shells it is often easy
It has an interesting and uniform angle which can be seen and measured - picture 5.
I have found some cell phone apps are quite useful for some things - more in another Observation.
But no special skills or apps are required for the Pullet. It even looks like a squat hen at times - pictures 6 & 7.
It often has a blue tinge to the inside wings - picture 8. Actually it's a rather nice shell!
See http://www.fao.org/fishery/culturedspecies/Venerupis_pullastra/en
We must show some inside detail if we want our marine shells identified. The outside shapes, colours and textures are often lovely but will not always lead to a definitive ID.
Externally Spisula solida is the perfect triangle - picture 2. Inside it is solid and chunky Picture 3. It has a few strong features to help ID - pictures 4 & 5 & 6.
There is surprise if you look closely, inner serrations in the teeth sockets - picture 7.
All Marine shells need careful examination. This is best done at a base where they can be washed, possibly scraped down and photographed in even lighting.
It's best that you learn which is the right or left valve and perhaps which is the posterior or anterior ends. Field-notes can be invaluable if collecting a few shells in one trip.
See
https://naturalhistory.museumwales.ac.uk/britishbivalves/browserecord.php?-recid=311
We must show some inside detail if we want our marine shells identified. The outside shapes, colours and textures are often lovely but will not always lead to a definitive ID.
The Blunt Gaper is one shell, however, that should be easy to ID from a single picture. It is so truncated and 'oddly shaped' that nothing should stand in your way.
Its sister Mya arernaria (Picture 2) is the closest in shape but goodness, so different in outline. The posterior end of M.truncata is abruptly blunt and, if you have the two halves, that end will not close - it is not called sand gaper for nothing. Further, the left valve has an amazing chondrophore (Picture 3) - a great 'inner-ear' which cannot be missed, though it is sometimes broken or worn half-away.
Truncata also has some really strong internal structures and they SO worth observing and recording.
The pallial lines and sinus are unique and usually easy to see Picture 4.
On the beach, even alongside big shells like (Lutraria lutraria) they are quite distinctive - Picture 5.
.
See
https://naturalhistory.museumwales.ac.uk/britishbivalves/browserecord.php?-recid=103
Shells are not always perfect for ID.
(Picture 8)
When found on the shore they might be well worn and have been in the sea for years. It is quite rare to find perfet clean examples of paired halves - both valves.
Rayed Artemis often has lovely brown rays on the outer surface. But it is the general, almost round shape that gives the first clue.
Examining the inner structure usually leads to a definive ID but, in this case the sister, Dosinia lupinus is quite hard to separate. D.exopleta is larger than D.lupinus but they all come in juvenile sizes of course. The real key is the hump and notch on the shoulder, as the teeth, pallial lines, and general stucture are too similar to call.
See https://naturalhistory.museumwales.ac.uk/britishbivalves/browserecord.php?-recid=50
and D.lupinus
http://www.idscaro.net/sci/04_med/class/fam5/species/dosinia_lupinus1.htm
Macridiscus multifarius from Uido, Sinan, South Korea.
Macridiscus multifarius differs from M. aequilatera in having a subtrigonal shell and in being more inflated… M. multifarius is found in Japan, Peter the Great Bay in Russia, Korean Peninsula and northern China (Kong at el., 2012) -https://academic.oup.com/mollus/article/78/1/1/1099170?login=false
Generally, Macridiscus found in East Sea of Korea(to Pohang) were aequilatera, while ones from West Sea were multifarius. It’s confirmed by Ron Noseworthy that both species inhabit in sea area of Jeju Island. More specimens from South Sea are needed to better understand the distribution of each species in Korean Peninsula.
Lead photo shows the interior of the shell, where the confluence of the pallial line with the pallial sinus can be seen. Lutraria angustior has a much thicker and heavier shell than Lutraria lutraria, and as a consequence the adductor muscle scars are larger, and the chrondrophore pit are bigger to accommodate a larger ligament.
The beak is a little nearer the anterior for the Lutraria angustior, and the posterior is that bit narrower. A very striking difference is that of the masses, and for an almost identically sized shell the Lutraria angustior has almost three times the mass of its relative.
Photos 3 and 4 are for comparative purposes.
For reference see:
https://naturalhistory.museumwales.ac.uk/BritishBivalves/browserecord.php?-recid=81
https://naturalhistory.museumwales.ac.uk/BritishBivalves/browserecord.php?-recid=82
One of the curved Ensis species, of which there are three: Ensis ensis, Ensis magnus and Ensis leei.
Ensis ensis is reaches a maximum size of 120mm and specimen Is 145mm. This species is strongly curved and tapers towards the posterior. The specimen is roughly parallel. Thus ruled out.
Enis leei has an S-shaped pallial sinus. The posterior adductor scar is less than its own length from the pallial sinus. The anterior adductor scar is just longer than the ligament. Thus ruled out.
Ensis magnus can reach 150mm, and has a U-shaped pallial sinus. The posterior adductor scar is 1 to 1.5 times its own length from the pallial sinus. The anterior adductor scar is significantly longer than the ligament. This seems the best candidate.
See (Old names used):
https://naturalhistory.museumwales.ac.uk/BritishBivalves/browserecord.php?-recid=52
and
https://conchsoc.org/spAccount/ensis-arcuatus
This subspecies of Mimachlmys varia is limited to the West coast of Scotland and Ireland. It is usually white, and has more, finer ribs than the species. Typically more than 40, but often in the range 42-47. This is one of the largest ones I have found. This one like others of the subspecies is slightly less elongate oval than the species.
I have added a comparison photo with the species and the Queen Scallop.
For reference see:
https://naturalhistory.museumwales.ac.uk/BritishBivalves/browserecord.php?-recid=27
Broadly oval shell with the beaks in the anterior half of the shell. The dorsal margin breaks abruptly to the posterior.
The pallial sinsus is deep and goes beyond the midline. The sinus is confluent with the pallial line for a short distance, and there is only a narrow wedge between them.
The exterior has concentric ridges, but there are faint radial lines. The posterior area is much coarser.
For reference:
https://naturalhistory.museumwales.ac.uk/BritishBivalves/browserecord.php?-recid=331
From debris entangled in fishing nets. Fishing area Toroneos gulf at ~30 m depth.
Saw dozens (but it was a windy day, there was not much visibility). A colleague had seen hundreds in previous days, including groups forming rows on the sea floor.
Interesting link about the discovery/recording of this species in the Solent:
Paired Sand Gaper valves. Left valve shown uppermost with the more pointed posterior on the right. There is evidence of the periostracum so a fairly fresh shell. The spoon shaped chondrophore which is typical of Mya species can be seen in the second picture. The pointed posterior rules out Mya truncata
My fourth, maybe final, observation of this delight.
Partnered with -
https://www.inaturalist.org/observations/18435310
and
https://www.inaturalist.org/observations/18270468
It was once known once as the Hartlepool Horn Limpet.
HERE
It is worth reading on a little to get a feel for the language used in those days.
This was at a time when it was fashionable for biologists to vie with each other, often re-describing a well-known species again and again in the hope of attribution in the Nature journals of the day. Known then by a few as the Horn-shell, it was found on a beach in Hartlepool UK by James Petiver (c. 1665 – c. 2 April 1718)
The little jeweil-of-a-shell was known to, and named by, Linnaeus in 1758.
But I suspect he did not handle the late stage shell which, for a few years, was considered a separate species with various popular names. One, which hung on for years, was Patina pellucida leavis (Pennant, 1777)
But in 1778 Emanuel Mendes da Costa wrote
"This species of Limpet in its states of young and old is extremely different that it seems two distinct species and for such authors have both figured and described them."
The rest, of course, is history
Collaret de sorra. Posta del cargol de lluna.
I have visited 10 distilleries where this fungus is rampant. Usually expresses as sooty staining on external walls, nearby trees, signposts and street furniture. It forms on structures up to 600 metres (downwind?) away from Distilleries and Bond Warehouses. It is known to cause unsightly staining on nearby modern dwellings.
It is granular and can be scraped from the surface and cultivated. Here we see examples on structures at the Blair Athol Distillery, as well as one or two from other locations..
3 Pictures showing the distinctive spore chains
https://en.wikipedia.org/wiki/Baudoinia_compniacensis
(Edited 22 Dec)
At first glance you may think I have made a mistake here. But ALL the shells are of Patella pellucida.
These are late-stage shells. Probably in their third, up to fifth year, the young molluscs make their way from the frond of, mostly, kelp to the lower parts of the stipes (stems). There, they feed into the tough tissue and take on a horn-like colour and grow to an absolute max of 3cms (2.76mm in Orkney). It is these specimens that were given another name Patina pellucida leavis because they were seen for a long time as a separate species but they are not.
At this stage they loose their delightful jewelled appearance and take on the shape of the rounded stipe (stem) but retain their overall patella appearance but without ridges.
Nice specimens show remnants of the blue rays but also elusive underlying red ones.
Get your eye in and you will find this shell mixed in with common limpets, on the beaches of the north-eastern Atlantic,
the one USA record has an interesting story.
See the record - https://www.biodiversitylibrary.org/page/27054800#page/267/mode/1up
.
Follow the story here -
https://www.inaturalist.org/observations/18435310
.
See - https://www.marlin.ac.uk/species/detail/1298
On Quercus ilex, with mosses. Thallus with transparent hairs.