SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8d7042ce39d2032bb24939ff32c80c7b31b7b5c3015d8cf9cdb7571f552fc43e' 
  AND token = '91QsoVfErriJhFHqJz+fS+PZZd66cRxKhIVfy/AgkW0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00047

JSON explain

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