BIOLOGY, LIFE-CYCLE AND REDESCRIPTION OF NEOAPLECTANA-BIBIONIS BOVIEN, 1937 NEMATODA, STEINERNEMATIDAE

Abstract

Study of the morphology and development of the infective 3rd larval stage of N. bibionis Bovien, 1937, a parasite of arthropods, made it possible to recognize the 2nd larval stage and present a description of all developmental stages in the life cycle of the species. Four larval stages were recognized. L1 hatches from the egg. In a suitable host, when the population density is low, it develops directly into L4. When the population density is high, it develops into L2. L2 is a non-feeding stage that precedes the resistant infective L3 larvae. L3 is free-living and characterized by a distinct lateral field with 9 longitudinal lines. In the L4 the sex can be recognized. The 1st adults developing in a fresh host are usually larger than those developing later. Generally, no more than 2 generations are completed in 1 insect. Young females in a fresh host lay eggs. In older females and in females developing in a decaying host, endotokia matricida is common. A redescription of the species is presented on the basis of a population from New Zealand reared on Galleria mellonella larvae. All stages of the life cycle are described and illustrated. Proposed new synonymy includes N. leucaniae Hoy, 1954 a synonym of N. bibionis Bovien, 1937 and N. affinis Bovien, 1937 a synonym of N. menozzi Travassos, 1932.