One in command or very successful (4,2,3,4)

Kidnap for naval service; press (8)

Piece next to a knight on a chessboard (4)

Ashes: stays (7)

Accustomed; par (5)

Rate: central nervous system stimulant (5)

In accord with the latest fad; stylish (7)

Support for a coffin (4)

Island in San Francisco Bay, once a prison (8)

Extremely disappointed and/or frustrated (4,2,1,6)

Quintessence; significance (4)

African country, capital Kampala (6)

Casually thoughtless or inconsiderate (7)

Part of a church in front of the altar often separated from the nave by a screen or rail (5)

One of the Seven Wonders of the Ancient World (6)

Numbers unsuccessfully competing in a race (4-4)

I exit PLC? (anag) (8)

Extractor used to deliver babies (7)

Interjection announcing a great discovery (6)

Improvement: throw over (6)

Gounod opera, primarily on Marlowe's play (5)

Old Testament minor prophet and book (4)