S. Mahunka szerk.: Folia Entomologica Hungarica 59. (Budapest, 1998)
The larvae are rather particular about their food: they feed upon fresh flowing sap. In connection with these habits, they are never found completely shaded. They live and move in the sap on the surface of the bark. If the quantity of sap is reduced, they move upwards, towards the source of sap. This is why we found them in bark crevices half covered, cranial half of body under the bark. They are unable to break (disconnect) bark, so they can use only bark surfaces proper for their life. And elm-trees has just this kind of bark structures. The timing of development stages is far more clear than with P. (M.) annulata. Numerous eggs were collected from sap (17 eggs preserved) on the 16th of May (cf.: first adults caught on the 23th of April), yound third instar larvae were caught on the 2th of June and the last adults were collected on the 16th of June. Consequently, it seems sure that the adults emerge from the last third of April to ca. end of May; they mate and females lay eggs from mid-May to mid-June (four adults were also collected in the Börzsöny Mts on the 10th of June); larvae develop into third instar (earliest by the first days of June) and go to sleep when sap flows stop. They overwinter as third instaar larvae or in puparia. It would be important to collect any larvae in early spring, in order to discuss this only obscurous point of their development. It is sure that it has one generation per year only. The life-habits of Periscelis winnertzii Egger, 1862 Material studied: 1 LI, 3 L2: (Börzsöny Mts.) Szokolya, Vasfazék-völgy, under Magas Tax, 450 m, from a wound of an oak tree, 13th September 1997, leg. László and János Papp; 9 L3: (Börzsöny Mts.) Szokolya, Királyrét, Szénpatak-völgy (valley), tölgyfa sebéből (from a wound of an oak tree), 14th May 1996; 1 pupal shell: ibid., 23rd May (it was kept as a larva in a vial with sap and wet corky oak bark in the lab at 20°C; it was a pupa on the 17th of June and emerged on the 13th of July as a female fly). 23 adults: Szokolya, Vasfazék-völgy, Sep 13, 1997, leg. L. (László) and János Papp. They were collected on black oozing wounds of two old oak trees. The above larvae (LI, L2) were picked out from wound sap runs, on which these adults were caught. From the above data we can sketch out the phenology of the development of this extremely rare species in Hungary. The adults emerge later to much later than the former two species (mid-July to early September). They mate and lay eggs until the first days of September and they develop into second instar (- at least so -) ir third instar larvae in September. It is absolutely sure that they overwinter as third instar larvae since we caught them as such on the 14th and the 23th of May. As for the former species, also P. winnertzii has one generation per year only. COLLECTING METHODS Adults As I noted above, the adults of periscelidids are rare indeed but mostly not collected even in the forests where they live. Bächli (1997) collected most of the Periscelis specimens by beer trap in ca. 5m high on the trees. This finding support again ours: the adults fly tree trunks upwards and change trees at the height of foliage. In addition, we found them on wound low on the tree trunks very seldom (if so, mostly in the first days of their flight period).
