SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1337c841872fde57e962788b8508d797c555b898e1627df913d3a53e86f1505f' 
  AND token = 'ITxiuk2PLZlWvgdZ7femAXYa8QWjKcwat1EdYtZoxIE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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