With the breakup of Pangea in the 200-100million year range,  the Tethys Ocean developed as a circumtropical ocean.  Thus, fossil faunas from southern Europe, northern Africa, southern Asia, the central eastern Pacific, and the Caribbean region are often relatively similar.  Most modern remnants of this fauna live in the Indo-Pacific.  Northward motion of India led to collision with Asia in the Eocene or so, roughly 45 million years ago, somewhat disrupting the eastern Tethys.  Meanwhile, northward movement of Africa and assorted small plates, now parts of southern Europe, constricted the central Tethys region.  Southern and eastern Europe developed a series of more or less isolated basins, with the Caspian and Black seas representing modern remnants.  At the end of the Miocene, about 6 million years ago, the northward movement of Africa and Arabia cut off both the Atlantic and the Red Sea connections of the Mediterranean.  There was extensive drying of the sea, although we do not know the extent to which it was actually dry versus very salty lakes on the bottom.  At the beginning of the Pliocene, 5 million years ago, the Straits of Gilbraltar opened.  The Mediterranean was re-invaded by Atlantic species at this point.  I do not know if there was any known connection to the Mediterranean after that point.  Sea level was well above the present at several points during the Pliocene, but I do not know if the Isthmus of Suez or other regions would have been low enough for marine connections to develop.

    Dr. David Campbell
    Old Seashells
    46860 Hilton Dr #1113
    Lexington Park MD 20653 USA
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That is Uncle Joe, taken in the masonic regalia of a Grand Exalted Periwinkle of the Mystic Order of Whelks-P.G. Wodehouse, Romance at Droigate Spa