Vol. 93, No. 1, January & February 1982 19 BIOLOGY AND LIFE HISTORY OF THE RICE FIELD PREDATOR ANDRALLUS SPINIDENS F. (HEMIPTERA: PENTATOMIDAE)i Gary V. Manley^ ABSTRACT: The pentatomid bug, Andrallus spinidens (F.), is a non-specific predator on Lepidoptera larvae in rice fields of West Malaysia. Large populations of A. spinidens were observed associated with outbreaks of Melanitis leda (Satyridae). Field and laboratory studies on the biology and behavior of A. spinidens were conducted to clarify its role in suppressing lepidopteran populations. Development from egg to adult averaged 26 days. During investigations of arthropod predators in rice fields of West Malaysia, the asopine pentatomid A ndrallus spinidens (F.) was observed to be a non-specific predator on lepidopteran larvae. Further studies indicated that Andrallus was a potentially useful biological control agent in rice fields. Laboratory studies were conducted for the purpose of gaining information on life history, behavior, and ecology of the species. Specimens were collected from rice fields in Province Wellesley and Kedah, West Malaysia. A review of the literature, distribution, and recorded hosts of Andrallus spinidens can be found in a paper by Kajendra (1971). Methods and Materials Studies were conducted on both field-collected and laboratory-reared specimens. For instar development studies, female pentatomids were placed in individual petri dishes for egg collection. After eggs were laid the females were separated from the eggs. Adults and nymphs were fed grain moth larvae and larvae of various lepidopteran species collected from the rice fields. Living larvae were given to each pentatomid daily. First instar nymphs were given damp cotton and left in the container with the eggs until they molted. After molting they were moved to individual dishes and reared to adults. Stock cultures were maintained in cages 3x3 feet in the laboratory in order to have specimens at various developmental stages for behavioral and ecological studies. Lepidoptera larval weights were determined by weighing the live larvae 1 Received April 4, 1981 ^MARDI, Bumbong Lima, Province Wellesley, Malaysia. U.S. Peace Corps Volunteer. Standard Fruit Company, Tropical Research Department-South America, P.O. Box 1747, Gulfport, MS 39501 ENT. NEWS, 93 (1) 15-20, January & February. 1982
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