SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a64ce101cfba5d41451e1a12a2045ecaa909e46a2fcf47013df023385a56469c' 
  AND token = 'Q2rz06xgU4Kq4M48mJiIgxmx4uba+lwzwOdLIbZ5kpM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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