SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0bc79c80f7b9afe426eafd1ddc889090d6edccfae5b2327ea9284cd668a7aa58' 
  AND token = 'wYZH1KimbwOiZlVVYpy1m9wwQqtr+HyFbG0UbBguB+A=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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