SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '88e051cdd2317064baa801ba3a9a0ed1f026d9a5705f00f0f72ac663cfd70255' 
  AND token = 'qhzqez/uj4AGrhB7mxh5x+wpjtIQuHthA4gG2qQRMLk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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