Cylindrocorpus inevectus sp. n. associated with the oil palm weevil, Elaeidobius kamerunicus (Faust) (Coleoptera: Curculionidae), with a synopsis of the family Cylindrocorporidae and establishment of Longibuccidae n. fam. (Diplogastroidea: Nematoda)

Abstract

AbstractCylindrocorpus inevectus sp. n. (Cylindrocorporidae: Nematoda) is described from oil palm flowers (Elaeis guineensis Jacquin) and from the under surface of the elytra of the oil palm weevil, Elaeidobius kamerunicus (Faust) (Coleoptera: Curculionidae) in Malaysia. Cylindrocorpus inevectus sp. n. differs from previously described species in the genus (as defined in the present study) by apparently having only eight pairs of genital papillae in contrast to nine or ten pairs. In addition, the male of the new species differs from C. macrolaimus (Schneider) and C. longistoma (Stefanski) by possessing a very short tail spine. The degree of stoma coverage by the pharyngeal sleeve is suggested as an important character and is 77% in C. longistoma but 91% in C. inevectus sp. n. In the male of C. erectus the bursa does not encircle the tail tip and the tail is much stouter than that of C. inevectus sp. n. In addition, there are only two pairs of pre-anal papillae and two pairs of dorso-lateral post-anal papillae in C. erectus but three pairs of pre-anal papillae and only one pair of dorso-lateral post-anal papillae in C. inevectus sp. n. From C. curzii the new species differs in having the bursal membrane continuing around the tail tip with only two pairs of pre-anal papillae reaching the bursal rim. A key to the genera of the Cylindrocorporidae is provided and Myctolaimus rifflei (Massey & Hinds, 1970) comb. n. is proposed. Because of their parasitic association with vertebrates and morphological characters distinct from those of the saprophagic Cylindrocorporidae, such as the corpus merging with the isthmus, the absence of a valve in the corpus, a posteriorly located vulva, the presence of lateral alae, a reduced number of genital papillae and ovoviviparous nature, members of the genus Longibucca, previously placed in the Cylindrocorporidae, are placed in the new family Longibuccidae fam. n.