SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '91aa1007f5b30010efab81e4a1ed2041196bc6d7aff57a0e406eb493dac1955c' 
  AND token = 'FfnmjXVakLlK9Eod6EEZyjRy1gld9ZYNg8VbcU9K/24=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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