SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '79d70437685f3aae32f75e74ba7543c748d7820df460c3c57a90ec6532d77112' 
  AND token = '57s91BqELJtg+exSFMv3xij16oiaG4lLvRnA6FXQRo8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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