SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a9ef1c87652d053d9b41fa833c0ed2bb605bae8ddb4cb0d57371cbab0a6159fd' 
  AND token = 'xwn9g3tyidcRW/NrSVxQg1rWf910r81U05VrJAeLHPo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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