Pratylenchus zeae
Graham, 1951

Measurements (from C.I.H. Descriptions of Plant-parasitic Nematodes)
L = 0.47 mm; a = 26; b = 5.9; c = 21; V = 70; spear = 16 um
L = 0.40-0.42 mm; a = 27-32; b = 3.6-5.0; c = 17-21; T = 30-44; spear = 15 um

Description (from C.I.H. Descriptions of Plant-parasitic Nematodes)
 Female: Body slender, almost straight when relaxed, marked by very faint annules.  Lateral field with 4 incisures extending along tail beyond phasmids; the inner band shows a slight irregularity in the mid-body region but no corresponding 5th line is seen in transverse section.  Lip region not set off from body, bears 3 annules.  Outer margins of heavily sclerotized labial framework extend into body about one annule.  Spear 15-17 um long, with broad, anteriorly flattened basal knobs.  Orifice of dorsal oesophageal gland about 3 um behind spear base.  Hemizonid about 2 body annules long, just in front of excretory pore; hemizonion 9-11 annules behind hemizonid.  Ovary not extending to oesophagus, with oocytes in double row, except for the last 2 or 3.  Oviduct indistinct; uterus short; Spermatheca round, small, without sperms ( even in the only population recorded with males): the “Spermatheca” full of sperms described by Merny (1970) was, in fact, mature eggs of granular appearance.  Vulva at 68-76% of body length.  Post-vulvar uterine branch short, 1-2 body widths long, with rudiments of ovary.  Intestine with a short post-rectal extension dorsally.  Phasmids slightly posterior to middle of tail.  Tail tapering, with 16-25 annules in a Senegal population (25-27 according to Seinhorst, 1968): terminus variable, generally almost pointed, narrowly rounded to subacute, unstriated.
 Male: Extremely rare, found only once in Ivory Coast (Merny, 1970), not essential for reproduction.  Similar to female except for sexual dimorphism.  Spicules slender, ventrally arcuate, 14-15 um long; gubernaculums 4-5 um in length; bursa margins faintly crenate.
Type host and locality: Roots of maize (Zea mays), Florence, South Carolina, USA.


Measurements (from Sher & Allen, 1953)
L = 0.36-0.58 mm; a = 25-30; b = 5.4-8; c = 17-21; V = 68-76; spear = 15-17 um

Description (from Sher & Allen, 1953)
    Female: Lateral field marked by four incisures.  Lip region not set off from body, rounded, bears three annules.  Outer margins of heavily sclerotized labial framework extend into body about one body annule.  Spear-guiding apparatus extend posteriorly from basal plate about four body annules.  Spear 16 um long with broad flattened basal knobs.  Orifice of dorsal esophageal gland about 3 um behind spear base.  Hemizonid just above excretory pore, about two body annules long.  Ovary does not extend to esophagus, consists of double row of ooctyes.  Oviduct indistinct.  Uterus short.  Spermatheca or spermatozoa not seen.  Posterior uterine branch short, about width of body at vulva. Phasmids slightly posterior to middle of tail.  Four lateral lines extending past phasmid.  Tail tapers, terminus almost pointed.  No striations around terminus.
Type host: Roots of corn.
Type locality: Florence, South Carolina.


Description (from Roman, Hirschmann, 1969)
 Females: Lateral field often marked by four incisures, but may exhibit variations.  Lip region continuous with body contour, generally bearing three annules, but occasionally three on one side and four on the other.  Refractive "ornamentation" of terminal end of vestibule lacking.  Median blades of cephalic framework thicker than sublateral blades.  Stylet knobs varying from rounded to anteriorly concave.  Glandular lobe of esophagus overlapping anterior part of intestine ventrally and slightly laterally.  One specimen with aberrant type of esophagus: glandular lobe overlapping intestine dorsally and laterally.  Hemizonid two to three annules long, located immediately, or one annule in front of excretory pore.  Gonad measuring 96.0 to 252.0 um, with small, empty spermatotheca.  Postvulvar uterine branch 21.0 to 31.2 um long.  Oogonia observed in posterior branch.  Tail generally pointed, but may exhibit much variation.
 Males: Not found.