Filenchus annulatus
Siddiqi and Kahn, 1983
Photo Gallery- Konza Prairie

Dimensions:  5 females (paratypes):  L = 0.38-0.41 mm; a = 30.7-36.6; b = 5.4-5.7; c = 3.08-4.2; V = 61.9-63.7; stylet = 7-8um
                    Female (holotype):  L = 0.41; a = 31.5; b = 5.7; c = 4.1; V = 63.7; stylet = 7um
Eelworm slender, ventrally arcuate.  Body tapering towards both the extremities.  Cuticle finely striated with annules about 1.3um apart at mid-body.  Lateral field marked by four incisors.  Head continuous, smooth and anteriorly rounded.  Two pairs of cephalids distinct on neck with each cephalid extending over to two annules, anterior pair located at 2.5um and posterior pair at 7.5um from anterior end.  Excretory pore located at 58um from head end.  Stylet small.  Opening of dorsal oesophageal gland located 1.5um behind stylet base.  Median bulb measuring 6um x 3.5um in dimension, rounded and muscular with weakly developed cuticular thickening.  Basal bulb pyriform .  Cardia present.
Vulva a transverse slit without lateral vulval membrane.  Ovary single, prodelphic and outstretched.  Post-uterine sac 1/2 of the corresponding body width in length.  Tail filiform measuring 100um i.e., 10 anal-body widths in length ending in a pointed terminus.
Male: not found.
Type habitat and locality:  Collected around the rhizosphere of potato (Solannm tuberosum), at Ooti, Tamil Nadu.
Diagnosis and Relationship: Lelenchus annulatus sp. n. comes close to L. cynodontus Husain andKhan, 1967 L. mirus and L. microdorus Chawla et al., 1969.  The new species, however, differs from L. cynodontus in having larger 'b' value and short stylet and also by having two pairs of cephalids on neck (b = 4.7-5.2; stylet 9-11um; and, cephalids indistinct in L cynodontus).  From L. mirus it differs in having longer body and shorter stylet and also by having two pairs of cephalids on neck (L = 0.35-0.38 mm; stylet 10-11um; and, cephalid absent in L. mirus).  The present species differs from L. microdorus by having more anteriorly placed vulva, longer stylet and also by the presence of two pairs of cephalids (V = 65-71; stylet 6-7um; and, cephalids not seen in L. microdorus).
(Description- Siddiqi and Khan, 1983)