SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f53d214beb071713625292697c7f494cfed619354a5124f53d01a215a43d4288' 
  AND token = '9bGObRs8FEQsRI24dmiNKbHYGc+kjvC4I6DI48BCkII=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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