S. Mahunka szerk.: Folia Entomologica Hungarica 48. (Budapest, 1987)

The two nymphal stages are easily separated since the protonymphs have two, while the tritonymphs have four genital suckers. The mites of both species are active and feed in the larval, protonymphal and tritonymphal stages. However, each stage ends with a quiescent period prior to molting. The average duration of each immature stage at 28 + 2°C, except the hypopial stage is given in Table 1. As shown from data in Table 1: eggs reach the adult stage in 7,5 ± 1.5 and 9 ± 3 days for Caloglyphus and Acotyledon

, respectively. WOODRING (1969) stated this period to be 6.5 days for C. anomalus at 23°C. Table 1 . Average duration of various stages of Caloglyphus bérlései and Acotyledon krameri at 28 ± 2 °C Caloglyphus bérlései Acotyledon krameri Stage No. of Duration No. of Duration individuals (days) individuals (days) Egg 100 1.5 ± 0.5 100 2.5 ± 0.5 Larva 90 2.0 ± 0.0 93 3.0 ±1.0 Protohymph 88 2.0 + 0.0 76 1.5+0.5 Tritonymph 49 2.0 + 0.0 61 2.0 ±1.0 A study of fecundity was carried out by using 10 pairs of mites of both species as individual pairs and records were kept of the number of eggs laid by each female / per day until death. Data in Table 2 summarizes the results on the Caloglyphus and Acotyledon species. The opposition period of the Acoltyledon species ranged betwwen 6 to 17 days with a mean of 13.1 days under laboratory conditions, within this period a female deposited from 286 to 1167 eggs, with a mean of 842.6 eggs. However, the number of deposited eggs was directly related to the period of oviposition, i.e. 9 days. On the other hand, 1167-1173 eggs were deposited in the period ranging between 15 to 17 days and the mean number of deposited eggs per day was 64.32 eggs. Eggs deposited singly and the majority were laid in the early day. The longevity of the Acotyledon female ranged between 7-50 days with a mean of 28.2 days. In the case of the Caloglyphus species, it is obvious, that the total number of eggs produced per female during this study ranged from 179 to 1656 eggs, with a mean of 755.7 eggs. The oviposition period ranged between 5-31 days, with an average of 15.9 days. Female lived in these tests for an average of 22.1 days, the longest record being 44 days. WOODRING (1969) recorded, that C

. anomalus female laid an average of 930 eggs in the feeding on mealworms and the longevity was 23.4 days at 23°C. On the other hand, the female of the same species laid 545 eggs and the longevity was 18.5 days'vwhen feeding on yeast. These differences may be related to the type of food and temperature. It was often necessary to add new males to the fecundity tests, for this reason no average male longevity could be established. Hypopial stage The factors, whether environmental or genetic, that control the development of the hypopial stage are unknown, POLEJAEV (1938) by using Glycyphagus destructor Schrk. found, that an increase or decrease on relative humidity from 80% resulted in an increase in the number of hypopi. DAVIS and HUNTER (1963) by using H. anops Griffiths larvae under different humidity conditions suggested that the hypopial stage could not be correlated with the relative humidity at which the larvae or protonymphs were reared. In the present work one type of study was conducted to determine, if the relative humidity at which the larvae and the protonymphs developed could be correlated with the proportion of hypopi produced. 100 larvae of both species were reared in petri dishes (9 cm in diameter), with yeasted Drosophila as a source of food and with a filter paper on the bottom, this experiment was repeated twice

. A few drops of water were added daily to every dish and all dishes were covered with Parafilm to maintain a high relative humidity. The dishes were checked daily to determine the forming