PROC. ENTOMOL. SOC. WASH. 86(1), 1984, pp. 110-119 ETHOLOGY OF ANOPLIUS TENEBROSUS (CRESSON) (HYMENOPTERA: POMPILIDAE) Steven R. Alm and Frank E. Kurczewski (SRA) Department of Entomology, OARDC, Wooster, Ohio 44691; (FEK) Dept. of Environmental and Forest Biology. SUNY College of Environmental Science and Forestry, Syracuse, New York 13210. Abstract.— Anoplius tenebrosus (Cresson) has one generation per year. Females and males emerge in mid-summer in upstate NY. The males die within a few weeks of mating. The females, after mating, feed on flowers, especially goldenrod, and dig overwintering burrows in the ground in late summer and fall. They reappear during the first warm days of spring, and nest in sandy areas bordered by woodlands. Females of A. tenebrosus hunt and capture a variety of errant spiders, especially Lycosidae. and store one spider in a shallow, single-celled nest. The prey is cached either on a low plant or on the ground during burrow con-struction. Transport of the spider to the nest is always backwards on the ground, the wasp usually holding the base of the prey's hind leg with the mandibles. The spider is pulled into the nest by its spinnerets. The wasp's egg is placed obliquely on the venter of the spider's abdomen. A. xiaticus (L.), a related Palearctic species, has almost identical nesting behavior as A. tenebrosus. Knowledge of the nesting behavior of pompilids is limited, especially in the subgenus Pompilinus. There are few particulars for the 1 7 Nearctic species in this group. Prey preferences of some of the species are narrow, whereas those of others are broad (Evans, 1951). Anoplius tenebrosus (Cresson) is one of the commonest pompilids in this subgenus in the Canadian and Transition Zones. The species "occurs in sandy places, particularly in the vicinity of woods; the nest is a short tunnel in the earth with an enlarged terminal cell" (Evans, 1951). Prey spiders comprise Thomisidae and Lycosidae (Evans, 1951; Evans and Yoshimoto, 1962; Wasbauer and Powell, 1962). Evans (1970) observed Anoplius tenebrosus at Jackson Hole, Wyoming from July 4 to August 26. He indicated that females may overwinter because they appear early in the season and that males and fresh females emerged about July 20 after which mating took place. Records of A. tenebrosus occurring in the Northwest Territories and the Yukon, Canada were published by Steiner (1970). Kurczewski and Kurczewski (1973) reported Gnaphosidae as a new prey family, described burrow construction, prey transport, nest structure and dimensions, and indicated that females may overwinter. Our paper describes the ethology of .4. tenebrosus. The behavior of this species is compared with that of the related Palearctic Anoplius viaticus (L.). Location of nests. — Natural nesting sites comprised sand bordered by wood-lands. Data were collected at three sand pits near Mallory, one near Fulton, and
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