SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4859cb34aa848240991a18119c718c69fa3e92805e27c79d93d1816e5ac7af29' 
  AND token = 'HTFEpiYeX+sn8if1PhNezsX6BtFzo5+cWl0FR+Ba2pE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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