Genus Isolaimium
Cobb, 1920 (emended)
Diagnosis: Isolaimiidae new family. Body elongate (3-6
mm). Cuticle annulated, at least anteriorly; punctations set in longitudinal
and transverse rows (probably always present; sometimes faint or visible
only on tail). Lateral chords faint. Six hollow tubes surrounding
mouth and stoma. External circle of six large recessed papillae;
second circle of six smaller papillae. Amphids arpparently absent
or represented by dorso-lateral papillae of second circle. Esophagus
clavate, with thickened lining. Stoma long, triradiate, cuticularized,
usually with thicker walls near anterior. Cardia long, cylindrical.
Vulva transverse; female gonads amphidelphic, with flexures. Male
gonads diorchic, outstretched. Spicules thick, cephalate or non-cephalate,
internally divided or not. Short parallel gubernaculum with two short
posterior apophyses. Preanal, midventral papillary supplements in
male. Large caudal papillae on male tail and fine papillae on female
tail. Tails short, conoid, with bluntly-rounded to pointed tip.
Type species: Isolaimium papillatum Cobb, 1920.
(Description- Timm, 1968)
Emended description of the genus Isolaimium (Swart & Heyns,
1991)
Diagnosis: Isolaimidae. Body elongate, 3-7 mm. Cuticle
marked with punctations set in longitudinal and transverse rows, forming
transverse striae and longitudinal lines over varying parts of the body,
depending on the species. Punctations distinctly visible or faint.
Head sensilla represented by familiar compliment of six inner labial receptors
(represented by six tubes), six outer labial papillae, four cephalic papillae
and two laterally situated pore-like amphid apertures. Oesophagus
cylindrical to clavate, its lumen minute but with well-sclerotized radii.
Stoma long, tubular, triradiate with sclerotized walls which are thickened
towards the anterior. Cardia long, cylindrical tp pyramidal, dorso-ventral
in symmetry. Seven oesophageal glands observed in one species, number
and postition unknown in other species. Vulva tranverse, female gonads
didelphic, amphidelphic. Male gonads diorchic, outstretched; spicules
thick, arcuate to falcate, cephalate or non-cephalate, internally divided
or not. Short gubernaculum has two (or four) apophyses. Papilloid
supplements in male pre-anal, midventral. Caudal papillae present
on tails of both males and females. Tail short, conoid, with bluntly
rounded to pointed tip.
DNA Sequences Obtained