Scanning Electron Microscopy of Xiphinema, Longidorus, and Californidorus Stylet Morphology


  • M. R. Cho
  • R. T. Robbins


Stylet ultrastructure of five Xiphinema, four Longidorus, and three Californidorus species was compared by scanning electron microscopy. Morphological differences were seen in the odontophores and odontostyle bases between the genera and some of the species. All Xiphinema studied had well-developed odontophore flanges; the Longidorus species lacked flanges, except for weakly developed ones in L. diadecturus; and none of the Californidorus had flanges. Three sinuses were present in the odontophores of all species. The sinuses varied in length depending upon species. In Xiphinema and Californidorus the odontostyle bases had distinct overlapping collars, but in Longidorus the collars were absent except for L. diadecturus. The odontostyle-odontophore junction from a lateral view appeared as a slanted transverse line in all the species, but in a dorsal view of Xiphinema and Californidorus it was V-shaped. Dorsal longitudinal seams of the odontostyle and odontophore were observed in all the species. The dorsally located odontostyle aperture was ca. 1 [mu]m from the anterior end in all species, except in one Longidorus sp. it was ca. 4 [mu]m from the end. Key words: Californidorus clavicaudatus, C. cylindricaudatus, C. pinguicaudatus, dorsal seam, Dorylaimida, Longidoridae, Longidorus diadecturus, Nordiidae, odontostyle, odontostyle-odontophore junction, odontophore, scanning electron microscopy (SEM), sinus, stylet morphology, Xiphinema americanum, X. bakeri, X. chambersi, X. coxi, X. rivesi.