Tylenchid entomoparasites isolated from Spondylis buprestoides (L.) and Asemum striatum (L.) (Coleoptera: Cerambycidae)
Tylenchid entomoparasites were isolated from two longhorn beetle species, Spondylis buprestoides from Tsukuba, Japan, and Asemum striatum from Ithaca, Tompkins County, NY, USA. Parasitic females and juveniles were obtained from S. buprestoides, where the female has a large body (5-6 mm long), clear stylet retracted into the body and degenerate anus and rectum, similar to some neotylenchids and allantonematids. By contrast, only stylet-bearing parasitic juveniles were found in eggs of A. striatum, and detailed morphological analysis was not done for this isolate. These two isolates of parasites were molecularly characterised, and analysed for their phylogenetic status based on the small subunit of the ribosomal RNA gene. The phylogenetic inference suggested that the two parasitic nematodes are close to each other, and to the siricidicola superspecies of the genus Deladenus, i.e., these two species and Deladenus form a well-supported clade. Because these two host beetle species belong to the same cerambycid subfamily (Spondylinae) from disparate locations, a subfamily-associated nematode parasite lineage may be revealed by further field surveys.