SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9072ecec0c9de333f08b9637f6f152c9ac46d066b7f35fd0ee43c1e88fdad7a9' 
  AND token = 'xM5a5EIYwwWJrzTIsjKeqfnYtBD58ZdnzTkRPWWE7QQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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