SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bd1ecded57dc519bd11d7f7cba2dc1189455fa9a78aa7812f666aba2c8a239a8' 
  AND token = 'X+wl3pv9ccRK+ecM+ta0SH1NUe0swZizKQFAQBC4Mx8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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