SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1fb4ba2426fb0ec4c54c27e44c5a3f510fca4779b4362a6c900233141b3fc9b2' 
  AND token = 'AbUeyMqadZcZqdsQxgWgBKmLbWIwmNfQ0fTNPFl96yQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00078

JSON explain

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