SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3f808ece45457324353e2adf249a1161a89dfc8bcdaa5ebe8025cd4a66128cf0' 
  AND token = 'e1h3hNOxYmlx0AfW3BapuS5pdNUUrV9guxVH9cScfrc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00014

JSON explain

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