SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'dfd74a093a58f1725eadd536dd81e64aa1826e8a0b0cba0e70710bbc536d1b1d' 
  AND token = '2YNjT/MmxEGZYlGSUF9rhncjpCjubc33b9RnHWstFsI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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