It seems that a brief herpetological respite from malacological
matters is the order of the day, so I'll offer my one memorable
experience with Bufo marinus, which goes back some thirty-five years
or so.  Even though I started collecting shells in  grade school,
herpetology was my principal interest during my high school years.  I
used to catch, trade and purchase the scaly/slimy critters regularly,
and I had a basement room full of terraria.  My mother's only rule -
no venomous snakes!  Anyway, when a fellow offered me a pair of "marine
toads", how could I resist?  When they arrived, I placed them into a
large terrarium, a home-made wood-box structure with a glass front and a
screened lid, which already held a few tree frogs (Hyla versicolor), pickerel
frogs (Rana palustris), and wood frogs (Rana sylvatica), a pair of spotted
salamanders (Ambystoma maculatum), a couple of ring-necked snakes (Diadophis
punctatus), two anoles (Anolis carolinensis), and a small box turtle
(Terrapene carolina).  The following morning the terrarium looked like the
aftermath of a hurricane.  All that remained was the turtle, one tree frog
huddled in an upper corner, one salamander that hid under a rock, and two
bloated marine toads.  My new guests had chowed down on the other frogs, the
snakes, the lizards, and one salamander.  After that I kept them in a separate
terrarium, and didn't put anything near them unless I intended it as toad
food.  Since then I have read that Bufo marinus will even eat mice and small
rats; in other words anything that moves and will fit in its cavernous mouth.
Okay, now for the conchological connection - have you noticed a couple of the
above genus names, or derivatives of them, popping up in your shell cabinet?
I refer of course to Bufo (meaning toad) and Rana (meaning frog).  In the
family Bursidae we have the genus Bufonaria, which includes the species
Bufonaria rana.  There is a Bursa (Tutufa) bufo and a Bursa bufonia.  The
family is just crawling with amphibians!  Guess that's why they're called frog
shells!  Let's not forget the closely related Ranella ("little Rana"), and in
an entirely separate family, the heavy, squat Thais bufo.  There was even a
Strombus rana named by Roding, a heavy, squat species as you might expect.
Today it's known as Strombus lentiginosus.