| Microdera punctipennis dzungarica Kasz.(Coleoptera: Tenebrionidae) and Anatolica polita borealis Kasz. (Coleoptera: Tenebrionidae) possess significant ecological and economic values. But we know little about their biologies and machnisms of adapting to desert environment. To facilitate studies on these aspects and get enough insects for investigation, rearing systems for Microdera punctipennis and Anatolica polita should be firstly established. Here methods for rearing the desert beetle M. p. dzungarica and A. p. borealis were presented. After adding sufficient water and sand to the mineral water bottle, water content gradation in the sand was formed by the capillary phenomena, the artificial arenas were used to rear larva supplied with wheat bran. Meanwhile, eggs, prepupae and pupae were maintained in glass caltures. The results showed that the beetles were able to complete their life cycles in this substrates. The survival rates of eggs,1arvae, prepupae, pupae and teneral adults in M. p. dzungarica were 84.19±1.66%, 60.25±0.20%, 83.27±2.83%, 86.53±2.35% and 92.42±1.59%, respectively; meanwhile, the survival rates in Anatolica polita borealis were 68.67±2.45%,61.31±7.76%, 84.68±2.35%, 88.45±2.75% and 90.56±4.20% respectively. They were available rearing methods for M. p. dzungarica and A. p. borealis. Based on the methods we investigated the biologies of the two desert beetles.M. p. dzungarica is a special species in the desert region of Central Asia. It had a one-year life cycle. It adopts nocturnality to survive desert environment. Female adults were larger than male adults, the female/male ratio was 1.04:1. The rearing conditions in laboratory were 30±0.5℃, 30±6% relative humidity (RH) and 16L: 8D photoperiod. Cannibalism could be avoided by rearing one larva in a bottle. A complete life cycle was obtained under this condition. It took 7.35 days on average for the egg embryogenesis. The larvae had 7 instars, duration in each instar prolonged 2.25 days. The mean duration of the larva, prepupa, pupa and teneral adult was 49.27, 7.05, 9.95 and 10.12 days, respectively. The coloration of each developmental stage was gradually changed from creamy white to light brownish or black. Female commenced oviposition upon its body color became black. On average each female produced 568 eggs life long.A. p. borealis is a special species in the desert region of China. It was diurnal and had an one-year life cycle. Female adults were larger than male adults, the female/male ratio was 0.75:1. Cannibalism could be avoided by rearing one larva in a bottle. A complete life cycle was obtained under laboratory condition (30±0.5℃, 30±6% relative humidity and 16L: 8D photoperiod). The egg embryogenesis took 9.05 days on average. The mean duration of the larva, prepupa, pupa and teneral adult was 73.03, 6.95, 9.95 and 25 days, respectively. The larvae had 9 instars, the duration of the 9th instar was about 21 days, longer than the others. The coloration changing of each developmental stage was similar to M. p. dzungarica. Female commenced oviposition upon its body color became black.In this paper, the abnormal antenna of desert beetle A. p. borealis were measured and described for the first time, using morphological structures revealed by microscopic techniques, including scanning electron microscopy. Results showed that the segments of the deformed antenna were significantly smaller starting from the 5th than the other normal antennae in sizes.The egg structures and biological characters of Tenebrionidae insect were observed under scanning electron microscope (SEM), at the same time, the egg dimensions were measured under stereomicroscope (Nicon SMZ 800). There was significant difference between M. p. dzungarica and the others, so as the A. p. borealis. But, M. p. dzungarica and A. p. borealis didn't have micropyle, aeropyle etal. It was different from Sternoplax souvorowiana Reitter (Coleoptera: Tenebrionidae). The features may be used as taxonomic characters for Tenebrionidae.Effects of various temperatures and relative humidities (RH0%, RH10%, RH20%) on the eggs of darkling beetles M. p. dzungarica and A. p. borealis had been investigated, meanwhile the ratio of egg length and width, the ratios of 50-egg weight and one female weight were measured. Results showed that water loss rates of desert beetles M. p. dzungarica and A. p. borealis were lower, but survival rates were higher than that of Tenebrio molitor Linnaeus (Coleoptera: Tenebrionidae). Eggs washed by water showed lower survival rates. The ratios of 50-egg weight and one female weight of desert beetles were higher than those of T. molitor. It seemed that the desert females invested more resources in each egg to make higher survival rate compared with T. molitor. The optimal temperatures of M. p. dzungarica and A. p. borealis were 36℃, higher than T. molitor (29℃); the developmental threshold temperature of M. p. dzungarica and A. p. borealis were 18.50℃and 19.90℃, higher than that of T. molitor (10.46℃); the effective accumulated temperatures of M. p. dzungarica and A. p. borealis were 76.83 day degree and 87.98 day degree, lower than T. molitor (112.46 day degree). It might be an adaptive mechanism to the temperature of the sand surface layer in the desrt environment. This paper also reported the stereomicroscope morphological featureres of larvae in M. p. dzungarica, A. p. borealis and Colposcelis microderoides microderoides. The larval morphometric data including cephalic capsule width and length, pronotum width and length, pigmentation area on cephalic capsule and total cephalic capsule area were measured. Furthermore, the ratios of them were calculated. Results showed that the 3 species larvae could be identified by the morphological features of pigmentation area on cephalic capsule and the ratios between pigmentation area and total cephalic capsule. All the investigations may fill up the deficiencies of desert beetles in our country. It may be useful for further studies on categorization and the physiological and molecular biological coping mechanism to desert environment.
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