Wednesday, April 21, 2021

The Tale of Liomera Tristis at Kahalu'u

     When you're playing cribbage, as Sandra and I do most every afternoon, the best you can do is hold for the run and hope that Lady Luck is on your side.  When it comes to snorkeling, the best you can do is get in the water as often as possible, be observant and, as in cribbage, hope that Lady Luck blesses your effort.

    Tuesday morning we showed up at Kahalu'u a bit before 9 AM.  While Yasuko was setting up the ropes and posting the admonitions (Don't step on anything!) I had a brief conversation with the boss, also known as Kathleen Clark-san, and then it was time to hit the water.  The tide was high enough that getting in was fairly painless, there was virtually no current  and the water was really clear.   

    Not too far out, I looked into a coral depression and saw a tiny xanthid crab.   John Hoover tells us that xanthid crabs are sometimes called dark fingered crabs, stone crabs or mud crabs.  Most are pedestrian in appearance and spend their lives in crevices or under rocks, so they are rarely seen.  

Liomera tristis,  Kahalu'u Bay, Hawaii Island April 2021

    This little crab, which was a mere 15 millimeters across his carapace, was very patient with me.  He permitted me to take four pictures over a couple minutes without moving a single one of those aforementioned  millimeters.  Either I was looking at the molted exoskeleton of a crab or, to paraphrase John Clease, he had ceased to be, he was bereft of life...he was an ex-crab.  Despite his apparent morbidity, and his being truly miniature, I could see that his walking legs were striped red and white, much like candy canes or the the stripes on the flag of our country.  (In foreign and domestic affairs may she always be in the right.  But our country right or wrong.  Stephen Decatur, loosely.)  As you can see, in addition to the stripes he does have dark fingers.

   The crab was well documented and one can only look at an inanimate object for so long, no matter how stripey, so I shoved off in search of other worthy critters and fish.  I turned over a couple shells, including this nice punctured miter, without coaxing any hermits to make an appearance. 

Punctured Miter sans hermit.  C'est domage.
    Towards the end of my swim I saw a pair of Achille's Tang and two female Pearl Wrasse.  Both pretty good species for Kahalu'u and I captured them in short video clips.  For those of you who prefer fish over crab, I am including those tasty morsels as a post script.  Finally, in the sand right outside the entrance was a large Reticulated Cowry.  As he wasn't moving, he did not rate a video.

    By this time, almost 10 AM, there we plenty of human bodies littering the rocky entrance, but soon I was up in the shelter, hailing Kathleen Clark.  Quick as a sea hare she had John Hoover's critter book.  The closest thing we found was Liomera rubra, Edwards 1865.  This small crab is pictured blow.

   I wasn't sure if Kathleen was willing to accept that identification, but I certainly was not.  Once I got the camera dried off and the SD card into the computer, I improved the picture to what you see above. 

    Now having a good look, I referred to that wonderful source for the identification of absolutely anything, Google Images.  Dr. Google, PhD did not disappoint me;  a few minutes of perusal revealed a picture, supplied by the floridamuseum.ufl.edu very similar to the crab I had photographed.  The picture had been taken in Guam and the name applied was Liomera aff. tristis

Liomera rubra, courtesy of the Crab Database, University of Florida.

    As it turns out, aff. is short for affinis which means that the species may be similar to another and the nomenclature is not finalized.

    As the crab was not in John Hoover's book, I forwarded it to the Great Oz.  He agreed that my identification was probably correct.  He had not heard of this crab before, but returned to me a reference from Peter Castro's checklist of Hawaiian Crabs:

Liomera tristis (Dana, 1852)
Carpilodes tristis (Dana, 1852a): 77 [type locality: archipelago Puamotensis ? (=Tuamotu Archipelago, French
Polynesia); type material presumed lost].
Hawaiian Is. records:
Carpilodes tristis (Dana, 1852) — Rathbun 1906: 842 [H.I.] — Edmondson 1946: 292 [Rathbun’s record]; 1962a:
248, fig. 8d [Rathbun’s record].
Liomera (Liomera) tristis (Dana, 1852) — Serène 1984: 59, fig. 19, pl. 5, fig. B [H.I.].
Taxonomy. Serène (1984)
Geographical distribution. Across Indo-West Pacific region.
Habitat. Intertidal, shallow subtidal.
 
    In the meantime, I had found the following reference:
 
 American Fisheries Society Special Publication 31 version 18-May-04  
2004  McLaughlin et al2005 Common and Scientific names of Aquatic Invertebrates...
Liomera tristis
Hawaii, Native                          McLaughlin, et al(2005) Occurence values: H

    For me, this was akin to a visitation from a friendly spirit.  In 2007 Sandra and I discovered a small hermit crab on the reef outside Alii Villas, where we lived.  Sandra worked the computer for all it was worth and we came up with the identification,  Calcinus revi.  This was the first record for the United States and we got some attention from two prominent carcinologists with an interest in small hermit crabs, Joseph Poupin, of the Ecole Navale in Brest, and Patsy McLaughlin of Western Washington University..  
Patsy McLaughlin 2007

 
    Before our next trip back to the PNW, Patsy had us put one of the three Ca. revis we had found in a small bottle filled with Southern Comfort (Patsy explained that this beverage is higher in alcohol than other whiskies) and we brought it to her at her home in Bow, Washington.  Bow was, at that time, extremely rural.  Patsy lived in a cabin completely devoted to the study of crabs.  She greeted us in her muddy yard bedecked in a flannel shirt stout trousers and Wellington boots.  She was accompanied by her two large dogs to whom she was feeding McDonald's Cheeseburgers, while berating them at the top of her lungs.  I must tell you, it left an indelible image.
 
    Soon enough she had our specimen under a microscope and confirmed our identification.

Sandra's delicate fingers and Calcinus revi.
   A year ago, I had the opportunity to write to Joseph Poupin, who informed us that Patsy had passed.  He sent along this photo he had taken of his fellow carcinologist and their friend Alain in a
restaurant in France.  (Hence, a French restaurant.)

   So here we are.  Its is far from clear to me how uncommon this little crab is.  Was the reference by Dr. McLaughlin the last time it was seen in Hawaii?  I have written to Dr. Poupin and I'm hoping that he will  confirm our identification and, at the same time tell us just how uncommon was this sighting.  Will I be referred to another esteemed carcinologist? In the meantime, I have had the opportunity to reflect upon my friend Patsy McLaughlin.  I'm sure she is out there on a beach somewhere, turning over rocks, looking for hermit crabs.

jeff

After only a few hours I received this email from Joseph Poupin:

Dear Jeff,

    What a nice surprise to get some news from you! I remember very well the time we were working together with Patsy. I feel like you: she was an incredible human being.    ...

    Your crab does not pose a real problem. Although we cannot see the carapace, the banded legs pattern plus previous records of this species in Hawaii in Castro list seem enough to propose with confidence Liomera tristis, a species widespread in the IWP, especially in Western and Central Pacific. You will find a few photos of this crab in my database.

Rare sightings of common species are not unusual for Decapoda, living mostly at night and experts in the art of camouflage.

I hope that you are still well and enjoy your life in Hawaii, far away from the COVID.

Take care of yourself.

Joseph that has kept the spirit of Patsy!

j


Achillles Tang, Kahalu'u  April 2021

 



 





 
 



 
Female Pearl Wrasse, Kahalu'u April 2021

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