Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd4f5271c6d2b56f03a366e1150cbadfcf8e3e537f4f6e9a08df4cbd38fcb026c' 
  AND token = 'XHu3i9IIDt1X9WpnNvmj1bR8mjd9TiiRC3EGuP9GUYg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}