DESCRIPTION OF BURSAPHELENCHUS-ABRUPTUS N-SP (NEMATA, APHELENCHOIDIDAE), AN ASSOCIATE OF A DIGGER BEE

Bursaphelenchus abruptus n. sp., an associate of the digger bee, Antho phora abrupta (Hymenoptera: Anthophoridae), is described and illustrat ed. Bursaphelenchus abruptus n. sp. can be differentiated from other s pecies of Bursaphelenchus by the absence of head annules, stylet lengt h, length of the postuterine sac, shape of female tail, spicule morpho logy, and male caudal papillae arrangement. Two plant-pathogenic fungi , Monilinia fructicola and Botrytis cinerea, and a Monilia sp. isolate d from an adult bee from Prince Georges County, Maryland, were good ho sts for B. abruptus n. sp. Dauer juveniles (JIII) of B. abruptus n. sp . were isolated from the reproductive tracts of A. abrupta from Montgo mery County, Alabama, for measurements and comparison with J2-JIII int ermolts from a 4-week-old monoxenic culture on Monilia sp. Gonad lengt hs in dauer juveniles isolated from A. abrupta were highly variable (4 9 +/- 23 mum SD; range 21-93 mum; n = 29) compared with J2-JIII interm olts from culture (28 +/- 7 mum SD; range = 16-42 mum; n = 16), sugges ting that postembryonic gonad development may continue while dauers ar e in the bee host. Adult males and females of B. abruptus n. sp. were examined with scanning electron microscopy (SEM) for ultrastructural c omparisons with other members of the genus Bursaphelenchus.