How to find small and tiny seashells to increase both your species count and iNat's species count

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In response to this recent iNat post:

https://www.inaturalist.org/posts/52872-one-sixth-of-all-named-species-tallied#activity_comment_347148b3-6979-4642-aee7-8ea1c596f889

I suggested that iNat observers could find a lot of additional species of shelled marine mollusks to add to the iNat named species total if people who are beachcombing tried to find more of the small and tiny shells.

It seems that most people only pick up shells that are about an inch in diameter, or larger than that. I suppose that is because they shell by walking along the beach until a shell catches their eye.

Instead I would recommend that people check the drift lines, the wrack lines on a beach, until they see a patch or a line that appears to have mostly small stuff in it, even though some of that might be broken fragments of shells and other detritus, rather than whole shells.

Pay particular attention to the surface of sandy beaches near jetties and piers, where the sea water tends to form eddies. Eddies are often the place where waves drop the smallest stuff they are carrying. Flat areas of a beach at mid-tide or low-tide level are often promising places to look for patches of small shells. Sometimes the sediment on the bottom surface of a tide pool or rockpool can be good too.

If you see a patch of fine detritus on the beach that you think might be worthy of investigation, kneel down or sit down, and take a closer look.

You can pick up the small and tiny shells and drop them into a suitable container. I like to use a plastic flip-top vial. If I am finding extremely tiny shells, I fill that vial with water -- that way even a very tiny shell (2 or 3 mm) will drop down into the water instead of remaining stuck to my finger when I try to add it to the vial.

Another collecting method is to simply scoop up all of the possibly relevant material, and put it into a ziplock snack bag. This material can be washed, dried, and sorted at home at your leisure -- so-called armchair collecting.

I myself wear neoprene knee and elbow pads with gel inserts when I do a lot of searching for tiny shells. That way I can kneel, and when necessary crawl, for hours on end, day after day, without scraping the skin off of my knees and elbows. And I use magnifying reading glasses to help me see the smallest shells.

While it is true that you are likely to find some small juveniles of larger shells, you are also likely to find a lot of species which never reach an adult size that is larger than half an inch, a quarter of an inch, or even smaller still.

If you happen to know a scuba diver, you may want to ask the diver if he or she would scoop you up a small ziplock bag of sediment from a quiet place that is likely to have a lot of small species, such as under a kelp bed, or off of the end of a coral reef. Those places can be very rich in tiny species.

Storing the tiny species of shells requires small glass vials or tiny plastic boxes and small slips of rag paper. Small shells can be stored in very small ziplocks that are 2 inches by one inch or 3 by 2 inches.

If you end up getting deep into this area of knowledge, you will find you need some good magnification at home. A good light and a head-mounted magnifier, a standing magnifier, or possibly even a binocular microscope may come to seem like a necessity.

With some notable exceptions, the literature on the super tiny shells, which are often known as micromollusks, can be sparse and sometimes hard to obtain. Many popular books don't include any or many micromollusks.

Shells a bit larger than micros are often known as "minis". I however don't like that term, as these are not miniature shells, but simply small species.

If you have any questions about this or similar subjects, feel free to ask me.

Posted by susanhewitt susanhewitt, June 02, 2021 16:22

Comments

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Thank you for this great knowledge! I will definitely put it into practice next time I am beach-combing. Have you considered putting together a guide or website of micomollusks to consolidate the available information, and include tips for ID? Eventually you could publish your own book on them if that's something you would be interested in doing.

Posted by cammie about 2 months ago (Flag)
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Every time I go to the beach I will do this from now on. If it’s ok I’ll probably be tagging you since my ID skills are birds and mammals of the pacific.

Posted by chrisleearm about 2 months ago (Flag)
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Hello Cammie!

I publish a lot of papers, and I always have a backlog of papers that I need to work on finishing, some of them major ones.

I don't have a good set-up for photographing micromollusks, a feat which can be quite challenging.

Each area of the world has its own fauna of regular-sized shelled mollusks and of micromollusks, and therefore there are are far too many micromollusks to include in one website or book. Some micromollusk families are mainly tropical, whereas others occur almost everywhere.

There is an excellent website for Southwest Florida which includes a large number of micromollusk species, as well as numerous larger species, and that website is here:

https://www.shellmuseum.org/shell-guide

An excellent book for the Bahamas which contains vast numbers of mollusk species of every size, and includes 170 Scanning Electron Micrographs of very tiny shells, is this one:

http://www.bahamianseashells.com

Posted by susanhewitt about 2 months ago (Flag)
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And here is a fun article about someone who ended up really getting into micromollusks:

https://www.sbnature.org/publications/blog/2/posts/61/the-world-is-her-oyster-micromollusks-are-kind-of-a-big-deal-for-young-scientist

But I do want to stress that there are many hundreds of small species that we haven't yet recorded here on iNat, species that are quite a lot bigger than micromollusks, and which don't require a microscope to ID.

And one other thing worth mentioning is that there is no agreement among scientists on what size limit defines a micromollusk.

Posted by susanhewitt about 2 months ago (Flag)
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Guides on where to find obscure organisms often left unnoticed by the naked eye are very helpful. Thanks for this, will have to employ it whenever I'm at the beach again.

Posted by kemper about 2 months ago (Flag)
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@chrisleearm -- Hey Chris, I will do whatever I can to help with ID-ing observation of yours. Just ping me on the observation page or message me. I should be good on ID-ing most marine mollusks of the mainland USA.

Posted by susanhewitt about 2 months ago (Flag)
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I read this suggestion by you before on iNat and on my last trip to the beach I collected many species 10mm or smaller. It´s fun for sure and I will keep it up on my next beach holiday. But it seems really difficult for those observations to go beyond genus level...some are even still at "Gastropod". I do sometimes tag people that might know more, but I guess I am still too hesitant to do that too often as I do not want to bother too much. Maybe I should do this more often if a observation lingers to long at high-level-IDs.

Posted by ajott about 2 months ago (Flag)
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Thank you! I've been thinking about grabbing a bag of sentiment from my local creek. Who knows?

Posted by ken-potter about 2 months ago (Flag)
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I currently have 147 obs that need IDs. https://www.inaturalist.org/observations?place_id=any&quality_grade=needs_id&taxon_id=47115&user_id=cammie&verifiable=any
Even if you could just do a few, I would appreciate it! I figure that some are "cannot be improved" due to not having the identifying characteristics in the photo and such, but I don't know which those would be, so if you could let me know, that would also be super helpful!

Posted by cammie about 2 months ago (Flag)
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Great ideas! I'm definitely guilty of being biased to bigger shells. My guess would be tiny terrestrial snails are also very under-observed on iNat.

Posted by muir about 2 months ago (Flag)
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I’m headed to the beach today. Hopefully will have a few things for people to ID.

Posted by chrisleearm about 2 months ago (Flag)
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@muir I struggle a lot with getting IDs for my tiny terrestrial snails.

Posted by cammie about 2 months ago (Flag)
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@cammie same here. Myself, I feel like I've developed a mental feedback loop with the iNat community -- I see and want to observe the species groups that get IDed on iNaturalist, that I know I can connect with someone knowledgeable and passionate about the observed taxa. And the species groups that don't get much attention on iNat, my eyes gloss over I think to some degree. Not a great habit admittedly! but a habit nonetheless....

Posted by muir about 2 months ago (Flag)
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@cammie, I think that I know someone who can ID your tiny land snails.

Posted by susanhewitt about 2 months ago (Flag)
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@chrisleearm -- ping me if there is something I may be able to ID.

Posted by susanhewitt about 2 months ago (Flag)
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@ken-potter -- fine-size flood debris beside rivers can be a great source of the shells of land snails and freshwater mollusks.

Posted by susanhewitt about 2 months ago (Flag)
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@susanhewitt I've noticed those tiny shells and keep telling myself I'm going to grab some to work on from out of Hell Creek where I think the diversity will be greater. But this year I really wan to work the tiny creeks and actually set up all my equipment next to a very tiny (low water) creek today with the hopes of riding my bike over later but it rained. I'm mainly after Darters this year and anything that come along. :)

Posted by ken-potter about 2 months ago (Flag)
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@muir I have that same exact feedback loops as well! I sometimes get excited about a taxon only to have all of my observations languish forever in "needs ID", which causes the excitement to fade.

Posted by hydaticus about 2 months ago (Flag)
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But it seems to me that eventually almost everything gets some kind of an ID put on it, even if it takes a year or more.

Posted by susanhewitt about 2 months ago (Flag)
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@muir and @cammie -- we should be able to get some level of ID on tiny terrestrial snail shells, with some help from one or two other mollusk people here on iNat.

Posted by susanhewitt about 2 months ago (Flag)
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@muir I have the same issue with many observations languishing. Especially fungi! :) I have found that I often have to ask for help. I copy and paste in the top eight ID'ers for a family, genera or suspected species and ask away. Sometimes nothing happens and other times I get some action. Good luck!

Posted by ken-potter about 2 months ago (Flag)
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@ajott -- I am glad to hear you already collected a lot of small material. I did have a quick look at your mollusk observations to see if I could improve the IDs, but most of yours are in areas where I don't know the fauna at all.

For everyone:

It is worth bearing in mind that it is good to try to make sure, as best as you can, that you photograph shells that are in reasonably good condition, not too terribly worn, extremely chipped or broken, and preferably not bleached-out to an unnatural degree of extreme whiteness by the sun.

Also for individual valves of bivalves, we almost always need an interior shot as well as an exterior shot. And with snail shells we need a dorsal view and an apertural view, and sometimes a lateral view as well.

Posted by susanhewitt about 2 months ago (Flag)
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For everyone: Please note that I am only really good at ID-ing the marine mollusk fauna of Western Europe, the Caribbean, and all the coasts of North America.

For the rest of the world I may be able to ID a shell to family, or perhaps to genus.

Posted by susanhewitt about 2 months ago (Flag)
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Thanks for al the valueable info!

Posted by ajott about 2 months ago (Flag)
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You are very welcome!

Posted by susanhewitt about 2 months ago (Flag)

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