SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '154b12e2374f28a64cf7bef9b6b1048f58dc849c5197aa42253ab04e93b760e7' 
  AND token = 'SKW5nSBZWXfW3kL2ClFE4nVYj3auXsTVh4ycqGX6Lzs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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