Rotylenchus Filipjev, 1936
Type species of the genus:
Rotylenchus robustus Filipjev, 1936
Anguillulina (Rotylenchus) Filipjev,
Gottholdsteineria (Andrassy, 1958)
Orientylus (Jairajpuri and Siddiqi,
Calvatylus (Jairajpuri and Siddiqi, 1977)
Interrotylenchus (Eroshenko, 1984)
Scutellonemoides (Eroshenko, 1984)
Varotylus (Siddiqi, 1986)
Morphological identification of the more than 92 nominal species of the
genus is difficult due to the overlap in ranges of many morphometric
characters. upplementary characters necessary in identification include
(such as lip annulation, lip shape, lateral field areolation, body
longitudinal striation, stylet length, dorsal pharyngeal gland outlet,
pharyngeal gland overlap, tail shape, vulva position, presence of males and
phasmid position) (Vovlas et al., 2008).
Labial region offset or continuous with body contours, anteriorly
rounded or flattened, generally annulated, with or without
longitudinal striae on basal lip annule.
field with four lines, with or without scattered transverse
Labial framework, stylet, and stylet knobs average-sized for the
family; knobs with rounded to indented anterior surface.
esophageal gland opening often very close to stylet (6 µm), but
with tendency to posteriorly directed migration (up to 16
glands overlap intestine dorsally and laterally; dorsal
gland more developed than subventral glands; intestine symmetrically
arranged between the subventral glands.
Two genital branches outstretched, equally developed; posterior
branch rarely degenerated (diovarial, amphidelphic).
Epiptygma (single or double) present.
Tail short, hemispherical, rarely with small ventral projection.
pore-like, small, near anus level. (photomicrograph of Rotylenchus
robustus from Half Moon Bay, California by I.A. Zasada)
Secondary sexual dimorphism not marked; sometimes anterior part of
male body slightly smaller than female.
[Ref: Fortuner, (1987).]
Six species of Rotylenchinae were identified from 5,451 soil samples from
throughout Great Britain.
Pararoylenchus ouensensis was found only from Jersey, Channel Islands,
Rotylenchus pumilis and R. buxophilus were mainly restricted to
Rotylenchus uniformis, R. goodeyi and R. robustus were found in
a wide range of soil types but R. robustus preferred more moist, alkaline
soils and was recorded at greater altitudes then R. goodeyi (Boag
and Neilson, 1996).
in California Nematode Pest Rating System.
All known Rotylenchus species. are obligate plant
parasites. They have a wide range of wild and cultivated host plants.They are
migratory ectoparasites, generally feeding on outer layers of root cells
without entering the roots. Consequently, the damage they cause is usually
limited to necrosis of those cells penetrated by stylet. Some of the species
have longer stylets, including R. cazorlaensis, R. magnus
and R. robustus which penetratwe root tissues to greater depth,
kill more cells and cause more extensive damage to the root (Vovlas et al.,
Roylenchus goodeyi was more often found associated with beech and
Scots pine while R. robustus preferred bog myrtle, oak and hawthorn (Boag
and Neilson, 1996).
At the population levels encountered there was no evidence of either inter-
or intraspecific competition within or between either R. goodeyi or R.
robustus (Boag and Neilson, 1996).
All the known Rotylenchus spp. are obligate plant parasites of a wide
range of wild and cultivated plants and are migratory ectoparasites that
feed on the surface of roots. They ectoparasites do not enter the plant
root; the damage they cause is usually limited to necrosis of those cells
penetrated by the stylet. Species with longer stylets (such as Rotylenchus
cazorlaensis, R. magnus magnus., R. magnus jaeni and R. robuG117s2.aspxstus 6)
penetrate the tissues to greater depths and cause more extensive damage to
the root. (Vovlas et al., 2008).
Boag, B.and R. Neilson. 1996. Distribution and ecology of
Rotylenchus and Pararotylenchus (Nematoda: Hoplolaimidae) in Great Britain. Nematologica
Fortuner, R. 1987. Rev. Nematol. 10:219-232.
Vovlas, N., Subbotin, S.A. Troccoli, A., Liebanas, G., Castillo, G. 2008.
Molecular phylogeny of the genus Rotylenchus (Nematoda, Tylenchida) and
description of a new species. Zoologica Scripta 37:521-537