Description of Bursaphelenchus abruptus n. sp. (Nemata: Aphelenchoididae), an Associate of a Digger Bee.

Bursaphelenchus abruptus n. sp., an associate of the digger bee, Anthophora abrupta (Hymenoptera: Anthophoridae), is described and illustrated. Bursaphelenchus abruptus n. sp. can be differentiated from other species of Bursaphelenchus by the absence of head annules, stylet length, length of the postuterine sac, shape of female tail, spicule morphology, and male caudal papillae arrangement. Two plant-pathogenic fungi, Monilinia fructicola and Botrytis cinerea, and a Monilia sp. isolated from an adult bee from Prince Georges County, Maryland, were good hosts for B. abruptus n. sp. Dauer juveniles (JIII) of B. abruptus n. sp. were isolated from the reproductive tracts of A. abrupta from Montgomery County, Alabama, for measurements and comparison with J2 -JIII inter-molts from a 4-week-old monoxenic culture on Monilia sp. Gonad lengths in dauer juveniles isolated from A. abrupta were highly variable (49 +/- 23 mum SD; range 21-93 mum; n = 29) compared with J2-JIII intermolts from culture (28 +/- 7 mum SD; range = 16-42 mum; n = 16), suggesting that postembryonic gonad development may continue while dauers are in the bee host. Adult males and females of B. abruptus n. sp. were examined with scanning electron microscopy (SEM) for ultrastructural comparisons with other members of the genus Bursaphelenchus.