Kaszab Zoltán (szerk.): A Magyar Természettudományi Múzeum évkönyve 68. (Budapest 1976)

Papp, L. ; Plachter, H.: On cave-dwelling Sphaeroceridae from Hungary and Germany (Diptera)

Among them there were also Helomyzid larvae, thus it was impossible to count the exact number of the Sphaerocerid larvae, probably it was several hundred specimens per decoy mouse. Some of the Sphaerocerid larvae were taken from the decoys into small plastic boxes and they were cultured (see Table 3/1). The data of the ontogenesis of the troglophilous Limosina species can be summarized as follows: The copulation of the imagos is very short. The couples were never found in prae-copula. The eggs were placed in groups of 3-10 but with some distance between each egg. The egg number per female is 50-60. The hatching of the larvae takes 2-3 weeks at 7.5 + 1.0 °C. The larvae are found within the tissues, where they concentrate at the lower side and between the muscle particles and the loam floor. The larvae start to wander in the culture boxes about a week before pupation. The pupae are found at the surface of the loam and in the loam fissures. The duration of the whole ontogenesis from egg to imago is 70-90 days (but probably the larvae were not cultured in the optimum conditions). It is obvious that the troglophilous or troglobiont species are not too specialized as regards the substrate of breeding. The larvae of the same Sphaerocerid species consume dead animals, wholly rotten wood and the mycelia of fungi (cf. rearing data of HACKMAN 1903. referring to Limosina species living also in caves). The life length of the imagos of the true troglophilous species was also determined (at 7.5 + 1.0 °C, 90-100°

O rel. humidity), yielding an average of 38 days. The maximum length of life of L. rakovitzai is 62 days. The true troglophilous Limosina species are rarely seen deeper than 50 m from entrance but since the micedecoys were placed at such a depth and were filled with larvae, it is obvious that they live also there, although they are rare in the innermost parts. While collecting Sphaerocerid imagos it was found that the species in the caves never fly (like many of the coprophagous species). Though they try to escape by running away or by jumps of 5-10 cm. This way of changing place is very similar to that of the Phorid species. In the entrance region of the caves the Sphaerocerids live together with a great number of other animals. The spiders (21 species were found in 23 caves) are possible predators of Sphaerocerids. In summer dead Sphaerocerids were often found in the nets of spider Meta menardi LATR. (twice in nets of Nesticus edlidanus CLERCK and once on nets of Meta merianae SCOP.). The other predators ma}^ be: Tegenaria silvestris L. KOCH and Linyphiid species. In the interior of the caves only the Linyphiid species are regarded to be possible predators (the commonest being Lepthi/phantes pallid us BLACKW.). The eggs and young larvae are attacked by the Parasit idae acari and by some Staphylinid species. Still we do not consider the predators in the caves to be important limiting factors of the propagation of Sphaeroceridae. The assumption does not seem impossible, although it was made on the basis of only insufficient data, that the abundance of the true troglophilous species in the interior parts of the caves depends almost exclusively on the quantity of the available dead organic matter (transported by cave water, sometimes also by wind). Thus, the periodicity of the incoming organic matters can strongly — although secondarily — influence the aperiodicity in the propagation of these species. As a general evaluation of the data, it seems very instructive and thoughtprovoking to compare the data obtained from the above materials with the Sphaerocerid fauna of small mammal burrows and nests, the ecological conditions of which are quite similar to those of the caves and vertical karst pits. The Sphaerocerid fauna of the caves are poorer (cf. FALCOZ 1915, HESELHAUS 1913, HACKMAN 1963, 1967, etc.), and in the caves the species, which do not live in small mammal