SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '74e67126374b4f39287aa3b8040da82d544ad0c0910b640c4926b364b24935a2' 
  AND token = 'JhOjuTClfJSH6ntXDwnQ9UezuauriwfpU5aIDqM/Sec=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

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