Judging by the setting, it appears to be an ancient Pleistrostream 18' dinosaur egg with a Tyrannotail, an extinct offshoot to the modern miid-century whale tail. The palm tree fossils used in the interior decor indicate the earth was experiencing global warming during this epoch, caused by the coal fired hookahs dinsoaurs smoked which eventually led to their demise. Had they only heeded the warnings from their Sturgeon General, Everett C. Ganoid, they might be with us today.
For a brief time, dinouaurs experimented with egg shells made of 2024-T3 aluminum instead of keratin fibers and calcite crystals. A door was installed to assist the young with the hatching process, as the alumunim skin was impossible to crack. When unearthed today, these ancient aluminum eggs make a cozy travel trailer after being mounted on a wheeled chassis. Nice find.