SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3e675f5b8fd8b853fbf1d7edda1b0e402a8dfd37a8243ab02ecc30b9c073a500' 
  AND token = 'A9zbMFKZxsgYppexCMSkykOCU/qpATxdKqEIbHAi65o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00014

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}