SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '452841232d2619f52f06b61e76d1ae26fbdda818d666b655270912b18d8e84dd' 
  AND token = '+KVB9Ym4TgutcLakmjUJdlOFQwcZQyoJ+b9rjikZIEg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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