Observaciones de dbarclay

Subtidal, mostly 10 to 15 meters deep. Shells were generally encrusted, but when encrustations were removed the iridescent periostracum was visible when wet. Iridescence ranged from greenish silver to gold depending on lighting. This species was practically lost to science, since the locality was only "Pacific Islands," although it is not rare at scuba depth under coral slabs around Christmas Island, Kiribati. It is likely a Line Island endemic. Thanks to Bill Lyons for tracking down the original publications and ID. No thanks to the authors, on both the internet and in print, who took these photos and removed the copyright notes and incorrectly claim they represent specimens collected in the Andaman Islands, which they certainly do not.

Shallow water on reef flat, mostly under slabs. Shells were generally encrusted, but when encrustations were removed the iridescent periostracum was visible when wet. Iridescence still returns when shell is wet. Common reef species.

Many dead shells on gravel bar with grass, most had apparently been dragged out by animals but very few of the thick-shelled species appeared to have been penetrated. Most appeared very recently dead, a few had tissue remnants, some were oxidized and had been dead quite a while. I suppose these pink nacred shells are Pleurobema sintoxia, although I have seen various authors refer to them by different names. The white ones may also be the same species, but there are differences in shape, shell thickness, periostracum, and degree of shell inflation. I need some verification on all of them.

This one is heaviest of all the shells I'm posting from the Black River. It's kind of heptagonal/angularly oval, white nacre but not as plain white as large R. ebenus, so I guess it's a Pleurobema. Whether it's P. sintoxia or something else, maybe one of you can tell me.

Many dead shells on gravel bar with grass, most had apparently been dragged out by animals but very few of the thick-shelled species appeared to have been penetrated. Most appeared very recently dead, a few had tissue remnants, some were oxidized and had been dead quite a while.

Although this species resembles the local Pleurobema species, I think this one is correctly ID'ed.

Many dead shells on gravel bar with grass, most had apparently been dragged out by animals but very few of the thick-shelled species appeared to have been penetrated. Most appeared very recently dead, a few had tissue remnants, some were oxidized and had been dead quite a while. I suppose these pink nacred shells are Pleurobema sintoxia, although I have seen various authors refer to them by different names. The white ones may also be the same species, but there are differences in shape, shell thickness, periostracum, and degree of shell inflation. I need some verification on all of them.

This one was dark pink inside, inflated, and very heavy.

Many dead shells on gravel bar with grass, most had apparently been dragged out by animals but very few of the thick-shelled species appeared to have been penetrated. Most appeared very recently dead, a few had tissue remnants, some were oxidized and had been dead quite a while. I suppose these pink nacred shells are Pleurobema sintoxia, although I have seen various authors refer to them by different names. The white ones may also be the same species, but there are differences in shape, shell thickness, periostracum, and degree of shell inflation. I need some verification on all of them.

This one was pale pink inside, inflated, and very heavy.