Mesocriconema ornatum
Raski, 1952
Female: 0.363-0.442 mm; a = 10.1 - 12.8; b= 35 - 4.4; c = 15.9; V
= 90.3 - 93.8%.
Male: Unknown.
LARVA. Spear length 43-46 um. Total annules 94 -
100. Longitudinal cuticular markings on posterior edge of annules
similar to but more strongly developed than in C. xenoplax.
FEMALE. Oral opening obscure, surrounded by conspicuous elevated
labial disc. Amphid apertures narrow dark slits on lateral margins
of labial disc which expands internally near base to accommodate amphidial
pouches. Sclerotization hexaradiate with innervations in four submedian
sectors. Sublateral lobes small, placed equidistant about labial
disc. First annule small, narrow, irregular in outline, never divided
into plates as in C. xenoplax, not retrorse. Second annule retrorse,
not set off from succeeding annules. Head presents a bluntly rounded
outline.
Spear length 48-56 um. Excretory pore
on 25-27th annule from anterior end of body. Vulva located on 7-9th annule
from terminus. Anterior flap of vulva forms two distinct points in
outline. Ovary extends 38.8 - 71.8% of body length. Anus on 6-8th
annule from end of body, often notches posterior edge of the annule. Terminus
with two lobes deeply cleft between presenting a bluntly rounded almost
truncate tail. Total annules 87-92.
TYPE HABITAT: Soil about roots of peanut, Arachis hypogaea.
TYPE LOCALITY. Near Albany, Georgia.
DISTRIBUTION. Other collections taken from soil from peanut fields
near Leesburg and in Worth County, Ga.; soil from a corn field, Perry,
Ga.; soil from potato field, Fort Myers, Fla.
DIAGNOSIS. C. cylindricum is most nearly related to C. curvatum
and C. lobatum. It differs from both species in the absence of labial
plates and by the pointed outline of the anterior vulvar flap. It
is further differentiated from curvatum in the presence of cuticular
markings on the larvae and from lobatum in the small size of the
sublateral lobes and the smaller number of annules.
This species keys to C. rusticum according
to Taylor (1936). The sublateral lobes of the lip region, the deeply
cleft lobes of the terminus and the fewer annules of cylindricum
differ from rusticum.
(Description- Raski, 1952)
