SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '024a5d182a99783e40bc84437112fba9b24916d59fc62debedb25d7385f76143' 
  AND token = 'RBN04BGAHpnm90tj3LgMMUNvqu8S+hIkrwNmXee/3zk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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