Bursaphelenchus trypophloei sp n. (Nematoda: Parasitaphelenchinae) - an associate of the bark beetle, Trypophloeus asperatus (Gyll.) (Coleoptera: Curculionidae, Scolytinae), in aspen, Populus tremula L. Nematology, 13(5) 2011: 619-636. 623 [Zoological Record Volume 147]