Bursaphelenchus rufipennis n. sp. (Nematoda: Parasitaphelenchinae) and redescription of Ektaphelenchus obtusus (Nematoda: Ektaphelenchinae), associates from nematangia on the hind wings of Dendroctonus rufipennis (Coleoptera: Scolytidae)

Two species of aphelench, Bursaphelenchus rufipennis n. sp. and Ektaphelenchus obtusus, were isolated from the 'nematangia', cocoon-like structures found at the base of the hind wings of Dendroctonus rufipennis. The nematangia contained adult females of E. obtusus and the dauer juveniles of B. rufipennis n. sp. Only B. rufipennis n. sp. could be cultured on Monilinia fructicola on LGPDA (lactic acid-treated, glycerol-supplemented, potato dextrose agar). The new species of Bursaphelenchus is described and figured and some additional morphological characters are ascribed to E. obtusus, E. josephi, E. sandiaensis, E. smaelus (= E. prolobos) and E. terebranus after examination of type and/or voucher specimens. Bursaphelenchus rufipennis n. sp. has an adult body length of ca 500-1000 [mu]m, medium a ratios (ca 25-38 for females and ca 30-40 for males), b ratios of ca 8-13 (female) and 7-11 (male), c ratios of ca 15-22 (female and male), c' ratios of ca 3-4 (female) and ca 2-3 (male), and is characterised by three incisures in the lateral field, mitten-shaped spicules and a conical female tail that curves ventrally and possesses a variable tail tip. The new species is morphologically closest to B. corneolus, B. curvicaudatus, B. gerberae, B. paracorneolus and B. talonus. Morphological examination of type and/or voucher specimens of five Ektaphelenchus species revealed coarse transverse body annulation and three pairs of male caudal papillae (except for the two species where males are not described). Clear typological differences were observed among these five Ektaphelenchus species in the structure of the lip region, presence/absence of stylet knobs and male spicule morphology. Although these characters have not been consistently documented in the past, they may be diagnostic for species in the genus. Molecular phylogenetic analysis based on SSU and D2/D3 LSU sequences revealed that B. rufipennis n. sp. was closest to B. paracorneolus and that E. obtusus was closest to species of Ektaphelenchoides and a Cryptaphelenchus sp.