SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd6d4ef069339e5c688f401b5941756d7f52ad7078b5fd3dbb009fbbba4e9cd4a' 
  AND token = 'bG+bcyyp2kJgm4QUhYZAHCLXjOdKzgk9w33l8ncdk6w=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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