Captiva Island yields three Elliptical Sportellas, a small shell, but a big story

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When I am in Lee County, on the Gulf Coast of Florida, I usually stay on the beautiful barrier island of Sanibel, and I often go shelling at the southern end of the island of Captiva, near Blind Pass, on a beach called Turner Beach. These days I visit Sanibel and Captiva for three weeks in early December, my first visit to the area having been in 2011.

During my visit in December of 2017, on Turner Beach I was very fortunate to find a left valve of a small (maximum length circa 10 mm) rare, white bivalve called the Elliptical Sportella, scientific name Basterotia elliptica. The valve that I found was chipped and overall in poor condition, but because it is a rare and interesting species which was previously unknown from the area, the Sanibel Shell Museum curator, Dr. José Leal, wrote a small column about the valve three years later, in 2020:

https://www.shellmuseum.org/post/shell-of-the-week-the-elliptical-sportella

My 1917 iNat observation of that shell is here -- and yes, in reality this valve does have a hole in the middle of it, a hole which had been touched-up in José's photograph of the valve, but which is left visible in my photos:

https://www.inaturalist.org/observations/9235188

I was able to recognize the identity of this shell because I was fortunate enough to have found one valve of the species many years ago, long before I started recording observations on iNat. That was on a small beach outside the capital of the island of Nevis, part of the country of St. Kitts & Nevis, in the Leeward Islands, West Indies.

The Elliptical Sportella is in the same genus as another small white bivalve called the Square Sportella, Basterotia quadrata. That species is also quite uncommon, but not nearly as rare as its sister species. I also know the Square Sportella from having found that species on Nevis. And in December 2015 and 2016, I found a few valves of the Square Sportella on Turner Beach, Captiva, and that was another new species for the area. I also found several more valves of the Square Sportella this past December.

In 2020, Dr. José Leal wrote a note about my Square Sportella valves from 2015 and 2016 here:

https://www.shellmuseum.org/post/shell-of-the-week-the-square-sportella

Both these little clam species are called "Sportellas" because they used to be in the family Sportellidae, and the genus Sportella. The family they are in now is known as Basterotiidae, named after the genus Basterotia. The family Basterotiidae is in the bivalve order Galeommatida, along with another two families: Lasaeidae and Galeommatidae. All of the bivalves in the order Galeommatida are small white clams that most shellers are hardly familiar with at all.

When I visited Sanibel and Captiva in April/May of 2021, Turner Beach was closed off completely for at least six weeks for a major rebuilding of the jetty, and a restoration of the areas surrounding the parking lot, all of which had suffered severely from marine erosion and from too much uncontrolled human use. But fortunately for me, in December of 2021, when I visited Sanibel and Captiva again, Turner Beach was once again open and accessible.

No shell piles formed next to the Turner Beach jetty while I was visiting this past December, so instead I spent a lot of time examining small, sparse lines of drift shells, stretching from about one quarter mile north of the jetty, to about two miles north of the jetty. I wear good-quality knee and elbow pads made of neoprene with gel inserts. That is so that when I see promising-looking patches and Iines of small beach-drift shells, I can get down on my knees and elbows and crawl along, searching really closely, and wearing magnifying reading glasses.

I carry a quart freezer-quality ziplock bag, and also a two-ounce plastic flip-top vial filled with tap water. The tap water is there so that that any small shell that I try to put into the two-ounce vial drops easily off the surface of my finger. I also bring along a tiny 2 ml plastic flip-top vial for any interesting shell I might find that is really microscopic in size.

My hunting for interesting small shells went very well on every visit I made to Turner Beach in December 2021. I was able to find quite a lot of rarities of various species. And on December 9th 2021, at about 4:40pm, I found an adult-sized left valve of the Elliptical Sportella in good shape. I was very happy to see it.

https://www.inaturalist.org/observations/102790795

And a few days later, on December 14th 2021, at about 4 pm, I found an adult-sized right valve of the Elliptical Sportella in extremely good shape. I was super happy then, and I knew that Jose Leal would be very happy too.

https://www.inaturalist.org/observations/103157790

José was indeed happy when I brought all my batches of great little shells into the museum to give them to the collection.
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Posted by susanhewitt susanhewitt, January 04, 2022 22:19

Observations

Photos / Sounds

What

Square Sportella (Basterotia quadrata)

Observer

susanhewitt

Date

December 13, 2021 03:23 PM EST

Description

I found maybe three valves of this species this beach a few years ago, before I started recording stuff on
iNat.

That discovery is recorded in the Sanibel Shell Museum Shell Guide and is credited to me.

Photos / Sounds

What

Square Sportella (Basterotia quadrata)

Observer

susanhewitt

Date

December 15, 2021 09:46 AM EST

Description

The lowest one is in pretty good shape, better than the ones I gave to the shell museum a few years ago in 2015 and 2016:

https://www.shellmuseum.org/post/shell-of-the-week-the-square-sportella

Comments

@susanhewitt So interesting and super rewarding, Susan! Thank you for sharing your shell-seeking techniques with us.

Posted by sadawolk 6 months ago (Flag)

You are very kind, Sandy! Thank YOU for all the plant ID confirmations you do for me.

Posted by susanhewitt 6 months ago (Flag)

And here are Scanning Electron Micrographs of two valves of this species: the first one is a half-grown (4.6 mm) juvenile shell (Recent) and the second image is a fossil shell of 6 mm, both images courtesy of @harrylee:

http://www.jaxshells.org/elliptica.htm

Posted by susanhewitt 6 months ago (Flag)

This week José let me know that he had photographed my nice new valves of the Elliptical Sportella and the Square Sportella, and that he had put the new photos up on the Shell Guide.

He also asked me what else rare I had found that might need to be photographed and go up there. I had a few suggestions.

Posted by susanhewitt 5 months ago (Flag)

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