SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '767a9dff570d58c55f01f85a36795bf958e874cf7e5636fa834eaeb10f14adb7' 
  AND token = '54htkT/mEMV6TepUsa++jQkB9crUFUz+iEEXPVpB85w=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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