SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '72b13291d158564b965aacee51edab50b9dcf2ec09699d642c368de3f4b2e971' 
  AND token = 'a7gAyBMzHCS95zqk0A1et43lDs6TRypPdYzQcqKxXX8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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