Pratylenchus  jordanensis
Hashim, Zeid (1983)
Dimensions:
 Holotype female:  L = 0.43 mm; a = 29; b = 5.2; bí = 3.5; c = 16.5; cí = 2.9; V = 30.5-79.3-3.3; stylet = 14.5 um.
 Paratype females (n = 14):  L = 0.49 ± 0.014 (0.38-0.59) mm; a = 29 ± 0.49 (26-32); b = 5.3 ± 0.10 (4.5-5.9); bí = (n = 13) = 3.8 ± 0.08 (3.2-4.1); c (n = 11) = 18.3 ± 0.88 (16.1-25.0); cí (n = 11) = 2.6 ± 0.12 (2.1-3.0); V = 77.8 ± 0.25 (75.1-79.1); stylet = 14.6 ± 0.05 (14.5-15.0) um.
Description
 Females:  Body almost straight to ventrally arcuate when killed by heat.  Annule width 1.0-1.5 um at mid-body.  Lateral field about ? of mid-body diameter, non-areolated and with four incisures; additional oblique striae often occur in the central band of lateral field at mid-body.  Inner incisures smooth, fusing in the oesophageal and caudal regions; outer incisures crenate.  Cephalic region low, 2.0-2.5 um high, with two annules and slightly offset from the body.  Cephalic framework sclerotized, with the outer margins extending into the body for almost two annules.  Stylet knobs indented anteriorly.  Vestibule extension 9-10 um long.  Anterior cephalids 2-3 annules behind cephalic region; posterior cephalids rarely observed, 8-9 annules behind cephalic region.  Excretory pore 1-13 annules anterior to the oesophago-intestinal junction, from 1-6 annules behind hemizonid and at 81.2 ± 1.52 (67-90) um from anterior end.  Hemizonid 2-3 annules long.  Hemizonion observed in four specimens, 5-9 annules behind excretory pore.  Orifice of dorsal oesophageal gland 3.4 ± 0.06 (3.0-3.5) um from stylet base.  Median oesophageal bulb 12.5-14 x 8.5-10 um.  Oesophageal glands overlapping the intestine, with the longest overlap ventrally situated and 39.0 ± 2.28 (29.0-52.5) um long; gland nuclei arranged almost in tandem.  Convoluted canals (= intestinal fasciculi) present in the intestinal region:  in a few specimens, extensive portions of these canals are evident, appearing to intertwine and, at least occasionally, anastomose; in others, only exceedingly short sections of the canals could be discerned, possibly due to the almost complete collapse of these structures during fixation and/or processing.  Post-rectal sac absent.  Vulva raised on a protuberance.  Vagina about ½ of vulval body diameter.  Genital tract monodelphic, prodelphic and 134.1 ± 4.81 (103.5-163.5) um long.  Columella distinct, but the number of rows of cells not determined.  Spermatheca devoid of spermatozoa, sometimes difficult to discern.  Oocytes arranged in a single row within ovary.  Post-vulval sac 16.2 ± 0.74 (13.0-20.5) um long, undifferentiated.  Tail conoid, with 21.4 ± 0.47 (19-24) annules (ventral side).  Tail terminus smooth, with a characteristic indentation observed only in lateral view.  Phasmids at 44.4 ± 1.60 (31.5-56) % of tail length.
 Males:  Not found.

Type Habitat and Locality
 Soil around roots of grapevine (Vitis sp.), Wadi Dhulail, Jordan.

Type Specimens
 Collected by the author in August, 1981 and January, 1982.  Holotype female and five paratype females at Rothamsted Experimental Station, Harpenden, Hertfordshire, England.  Five paratype females at Commonwealth Institute of Parasitology, females at Muséum national díHistoire naturelle, Laboratoire des Vers, Paris, France.

Relationship
 Pratylenchus jordanensis n. sp. is differentiated from previously described Pratylenchus species, except P. agilis Thorne & Malek, 1968, P. hexincisus Taylor & Jenkins, 1957, P. crassi Das & Sultana, 1979 and P. scribneri Steiner, 1943, by the absence of males, empty Spermatheca of the female, cephalic region with two annules and slightly offset from the body, short stylet (< 18 um), V coefficient less than 80, undifferentiated post-vulval sac (16.2 um in length) and smooth tail terminus.  It differs from the above-mentioned four species in the indentation of the tail terminus.  It also differs from P. agilis (as described by Thorne & Malek, 1968) in its shorter stylet (14.6 vs. 17.8 um) and apparently slower movements, and from P. hexincisus (as described by Taylor & Jenkins, 1957 and Thorne & Malek, 1968) in having four incisures on the lateral field, often with additional oblique striae in the central band at mid-body (six incisures, some of which are irregularly broken at mid-body, in P. hexincisus).  P. jordanensis n. sp. is also distinguished from P. crassi by the shorter stylet (14.6 vs. 17-18 um), the greater distance between the dorsal oesophageal gland orifice and stylet base (3.4 vs. 2.1 um) and the greater number of tail annules (21 vs. 12-15).  (According to Das and Sultana, 1979, P. crassi has a large oval spermatheca filled with spermatozoa; however, this structure was not illustrated for this species and males were not found).  P. jordanensis n. sp. is also differentiated from P. scribneri (as described by Sher and Allen, 1953, Thorne and Malek, 1968 and Roman and Hirschmann, 1969) by the slightly more conoid tail with a slightly narrower terminus, the greater distance between the dorsal oesophageal gland orifice and stylet base (3.4 vs. 2.15 um, the latter according to Roman and Hirschmann, 1969) and the inner incisures fused distally on the tail (apparently not fusing on the tail in P. scribneri).  Eight specimens of P. scribneri from the USA (California), originally identified by J. Roman, were made available to the author by courtesy of D.J. Hooper.  These differed from P. jordanensis n. sp. in the broader tail terminus which is not indented, the lower cí coefficient (2.1 (2.0-2.3) vs. 2.6 (2.1-3.0); n = 6) and the absence of intestinal fasciculi (1).  The lateral fields were difficult to discern on the caudal region of these specimens of P. scribneri, so that the apparent difference in lateral field morphology between these species and P. jordanensis n. sp. (inner incisures fusing in this region in P. jordanensis but not P. scribneri) could not be confirmed.  Moreover, the difference in the position of the dorsal oesophageal gland orifice between the two species is perhaps too small to be of diagnostic value.
 (1)  The intestinal fascuculi of P. jordanensis do not constitute a unique character within the genus Pratylenchus, I have observed similar structures in P. goodeyi Sher & Allen, 1953 from the Canary Islands.