Ahhhhh...one of my favorite spots on Earth...
apparently mourning doves are invading the keys! along with everything else that follows humans
this adult was pretty tattered but the dark spots on the forewings look as though they once could have been lustrous and full. plus the shape, size and location fit. Dryas iulia, that's my guess, any takers?
This Crown Cone, Conus regius Gmelin, 1791, was observed and photographed at the Houston Museum of Natural Science, Texas. The date stated here is when i photographed it, since there is no date on the specimen label.
This is a common species occurring from east Florida to Brazil, Caribbean and Gulf of Mexico, including Texas. In another record (here: http://www.inaturalist.org/observations/906219), I observed this species live off the Texas coast.
Like all other cone shells, this species is also poisonous, ans should be handled very carefully.
Read more about this species in Tunnell et al. (2010) Encyclopedia of Texas Seashells, p. 237.