SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5585e6d63385bf90620c4047d98996eb9e96183f7c478b425b669574c7164def' 
  AND token = 'Wk9HPCPnVeiVYZxZ/szJUP50ZvJdlKrpWbfrNkL96HA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00046

JSON explain

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