SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a0db52531c8266223cc244366b5862438ba27d95f7c39f053809ad65d6cb02eb' 
  AND token = 'sJonAGpKbTsVWqg0OE9LI8Q5t/s2qJHFuW4aVH9JOjA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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