Ábrahám Levente: Válogatott tanulmányok II. - Natura Somogyiensis 9. (Kaposvár, 2006)

Ábrahám Levente: Pit building ant-lion larvae effect to the distribution of the substrate particles in their microhabitats - Tölcsérépítő hangyaleső lárvák hatása a szubsztrát szemcsék eloszlására élőhelyeiken

ÁBRAHÁM L.: PIT BUILDING ANT-LION LARVAE 181 Table 2: Comparison of the distribution of particle sizes taken from the pit's side (ps) at the same sampling sites on sandy bedrock Samples Paired Differences t df Sig. (2-tailed) Samples Mean Std. Deviation Std. Error Mean 95% Confidence Interval of the Difference t df Sig. (2-tailed) Samples Mean Std. Deviation Std. Error Mean Lower Upper t df Sig. (2-tailed) TO-TP 0.061 0.11386 0.04026 -0.035 0.156 1.5 7 0.176 BO-BP 0.018 0.07248 0.02563 -0.043 0.078 0.69 7 0.513 detected even with the paired samples t-test (Table 2). Therefore it can be stated that there was no detectable difference between the preference of the particle size of the antlion larvae of Myrmeleon bore in open habitat and of Euroleon nostras in protected habitat. In spite of this, the proportion of the finer particles among the substrate particles was smaller in protected habitat than in open habitat. Comparing figures 9-10. and 11-12., a small difference can be seen between the substrate preferences of Mymeleon bore (TO and BO) and Mymeleon inconspicuus (NO and LO) in open habitat but this difference might derive from the characteristics of the habitats. In protected habitats on loess bedrock (NP) the larvae also gather finer substrates in their pits. The preference of the particle size fractions of 0.1-0.2 and 0.3-0.4 mm is high (Ei>= +0.6). It's probable that it is a characteristic of the habitat to what extent the loess particles granulate therefore in the cases of bigger particle sizes (0.4-0.5 and 0.5-0.8 mm) the same preference was observable. The transition is clearly noticeable in the case of the particle sizes of 0.5-0.8 and 0.8-1.0 mm. The particle sizes of >0.8 mm are rejected by the larvae of all three stages to a great extent (Ei>= +0.66). In protected habitat on clay bedrock the particle size preference of 0.3-0.4 mm particles proved to be stronger (Ei>= +0.52) than the preference of finer or coarser particles, irrespective of the type of species. In this type of habitat the particle size of >0.8 mm is avoided by the larvae; that is they throw out these particle from their pits. The sampling sites of clay substrate were a couple of kilometers away from each other within one region. No significant difference was shown between certain sampling sites (Table 1). At these sampling sites (KP, ZP, RP) no significant differences between the particle size preferences of the larvae of Myrmeleonformicarius ana Euroleon nostras (Table 3) were found. Table 3: The analysis of the substrate preference according to the sample taken from the pit's side (ps) in protected habitats on clay bedrock Samples Paired Differences t df Sig. (2-tailed) Samples Mean Std. Deviation Std. Error Mean 95% Confidence Interval of the Difference t df Sig. (2-tailed) Samples Mean Std. Deviation Std. Error Mean Lower Upper t df Sig. (2-tailed) ZP-KP -0.027 0.10107 0.03573 -0.111 0.058 -0.75 7 0.479 ZP-RP 0.0072 0.10432 0.03688 -0.08 0.094 0.194 7 0.852 KP-RP 0.0339 0.12664 0.04477 -0.072 0.14 0.757 7 0.474