译 名：
ON THE LIFE-HISTORY OF THE LEGUME BLISTER BEETLE, EPICAUTA GORHAMI MARSEUL, WITH A DISCUSSION ON HYPERMETAMORPHOSIS
作 者：
CHU HUNG-Fu and WANG LIN-YAOInstitute of Entomology, Academia Sinica
摘 要：
The legume blister beetle, Epicauta gorhami Marseul, is widely distributed in China. It attacks leguminous plants including different species of cultivated beans: alfalfa and locust, and also feeds on potato, eggplant, peanut, beet, cotton, etc. This beetle is frequently present in such numbers in soybean fields as to cause some alarm and sometimes a heavy damage. Its life-history is very interesting and complicated. Winter is passed in the fifth instar larval stage, known as pseudopupa, in the soil without earthen cell. The adult emerges in June and feeds in clusters on the tip of host-plant. At the end of June, 70-150 eggs are laid in a hole underneath the ground. The first instar larva, known as triungulin, appears in the middle of July, actively seeks grasshopper eggs for food and then transforms into scarabaeiform. There are altogether six instars in the larval stage. The fifth instar assumes the pseudopupal or coarctate condition and is followed by a further larval instar which is also scarabaeiform and does not feed. pupation takes place in the soil about the middle of June. It has only one generation a year.In literature, six orders of insects are considered to possess hypermetamorphosis. In Neuroptera they are represented by the family Mantispidae, in Coleoptera by Carabidae, Staphilinidae, Rhipiphoridae, Meloidae, Micromalthidae and Mylabridae, in Strepsiptera by many families, in Hymenoptera by Ichneumonidae, Chalcididae, Perilampidae and Pteromalidae, in Diptera by Acroceratidae, Nemestrinidae, Bombyliidae and Tachinidae, while in Homoptera, the Margarodes of Coccidae is also reported as hypermetamorphic.Based upon the body form and the mode of life, the hypermetamorphic insects may be classified into two main groups:a) The predatory type comprises those which do not lay eggs directly on hosts but leave their young to seek their own food;b) The parasitic type on the other hand, lay their eggs on hosts. Again, the predatory type may be redivided into two subtypes, i. e., the oligopod subtype and the apod subtype. Both are active, but the former possesses well developed thoracic legs while the latter is apodous.In general, hypermetamorphosis is considered as that when an insect in its development passes through two or more markedly different larval instars and is accompanied as a rule by a marked change of larval life. The hypermetamorphic insects are mostly carnivorous. In the majority of instances the first larval instar is campodeiform. During this stage it seeks out its future pabulum and having discovered it undergoes, in its subsequent instars, morphological transformations which adapt it to the changed mode of life. The female lays a large number of eggs because of the fact that the subsequent life is extremely precarious, and many larvae perish in the first instar. However, transitional cases are frequent, in which various instars differ considerabIy in shape and habit but have few morphological changes, as is the case with more pronounced hypermetamorphic forms. For instance, Certain parasitic rove beetles have slender active first instar larvae and grub-like succeeding instars. A few genera of Trichoptera have free-1iving slender first instar larvae and casemaking stout-bodied later instar.In this paper,the authors prefer to use scarabaeiform instead of caraboiform for the second instar larva of the blister beetle, since it possesses more scarabaeid characters than caraboid. The pseudopupa is actually a resting larva which possesses more curculionid larval characters than that of the scarabaeid.
