SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1fbb13e128d8f9db463f5c01f6e22086d7b1fe130032b580d0343c17ed119aa3' 
  AND token = 'KB75ZMEzwJaLzi8vDZshFpjQHJj1KNSsE/xARbH8UDo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}