Criconema (Nothocriconemella) permistum
(Raski & Golden, 1966) Raski & Luc, 1985
syn. Criconemoides permistus Raski & Golden, 1966
Nothocriconema permistum (Raski & Golden) De Grisse, 1967
Nothocriconemella permista (Raski & Golden) Ebsary, 1981
Avoca Prairie, Wisconsin
Sheeder Prairie, Iowa
Williams Prairie, Iowa
11 Females (paratypes): L = 0.34 mm (0.31-0.40); a = 9.8 (9-11); b = 2.9 (2.7 - 3.3); c = 16.5 (13-22); vulva = 86 (84-88); stylet = 86 um (77- 98); prorhabdion = 76 um (68 - 87); annules = 78 (75 - 81).
10 Males (paratypes): L = 0.37 mm (0.34 - 0.38); a = 16.0 (14-18); c = 8.5 (8-9); T = 34 (12 - 41); spicules = 41 um (40 -42); gubernaculum = 7.6 um (7-8).
Female (holotype): L = 0.40 mm; a = 10; b = 3.3; c = 22; vulva = 88; stylet = 84 um; prorhabdion = 75 um; total body annules = 76.
Body tapers slightly anteriorly to truncate, slightly rounded head. Lip region with two annules about equal in width (14 um), rounded and not retrorse, narrower than succeeding body annules. First annule slightly set off from second which is close to the succeeding annule. Lips, six, rounded and projecting, concave anteriorly. Amphids two narrow oval openings near oral aperture. The two subdorsal and subventral lips bear minute papillae associated with the innervations entering the respective sinuses of the head framework. Stylet long and slender, knobs about 10 um across. Excretory pore obscure on 23rd (22nd-26th on paratypes) annule, about the level of nerve ring, 108 um (100 - 115) from anterior end. Gonad obscure, outstretched in few specimens where seen. Spermatheca prominent at anterior end of uterus, usually filled with spematozoa. Vulva on 13th (12- 15th) annule from terminus, lips of vulva rounded, slightly retrorse, projecting just beyond outline of other body annules, simple oval in shape. Anus prominent on 7th (6th - 8th) annule from terminus, normally separated by 5-7 annules from vulva. Tail conical, annules increasingly retrorse, decreasing regularly in width to small rounded lobe as terminus. Cuticle smooth. Anastomsis rare, no sign of lateral field.
Male (allotype): L = 0.37 mm; a = 15; c = 8.2; T = 25; spicules = 40 um; gubernaculum = 8 um.
Body tapers slightly anteriorly to a hemispherically shaped head with four annules. En face view shows four small remnants of sublateral lobes and two small oval amphid apertures near oral opening. Head framework, as in quasidemani, has dorsal-ventral bridge setting off two kidney-shaped, internal openings laterally in which innervations to sublateral lobes and amphids are located. Excretory pore prominent 39 (36-39) annules, 105 um (93-111) from anterior end. Lateral field marked by two prominent lines. Between these, running longitudinally, can be seen a central light band which suggests two degenerate lines. These appear to diverge slightly and end irregularly on the tail but the outside two lines are the only strong consistent marks of lateral field and form delicate caudal alae ending about 10 um short of terminus. Tail tapers abruptly behind cloaca with sharply conoid shape diminishing to an almost effilate terminus. Spicules long and slender, definitely curved. Gubernaculum small and simple. Cloacal opening without sheath-like projection, instead it is slightly concave. Striations continue on tail almost to terminus but weaker on ventral side. Annules 2.5 - 4.3 um.
Type host: Swamp soil.
Type locality: La Rue Meares, Route 1, Nichols, Dillon County, South Carolina.
Diagnosis: This species is most closely related to quasidemani from which it differs in the tail shape, regularly conoid in permistus not markedly slender in last 3-4 annules as in quasidemani. Also the male cloacal opening of permistus is slightly indented and not projecting as in quasidemani.
(Description- Raski & Gloden, 1966)
Measurements (19 Females): L = 313 um (233 - 390); stylet = 73 um (68 - 78); V = 86.8% (82.9 - 91.7); Rv = 12 (11 - 14); R = 66 ( 64 - 70); Ran = 6 ; R van = 4; Res = 22 (20 - 24).
Associated plants and localities: Soil around roots of Phalaris arundinacea L. in Pammel Woods, Ames, Iowa; Sambucus canadensis L. and Rhus glabra in Pilot Knob State Park, Iowa; and an unknown plant species within a wet area in the Sheeder Prairie, Guthrie county, Iowa.
The most distinguishing characters of this species are the two naked offset annules and the two spines located on the lateral sides of the anterior vulval flap. The spines were not described in the original description, nor were they noted by Thorne and Malek (1968). De Grisse (1969) first illlustrated this character, which was found in all populations recorded from Iowa and is also present on paratype number 500, slide number 23L, from the Nematode Collection at the University of California, Davis.
It is evident from the literature and from specimens collected in Iowa that this species exhibits marked infraspecific variation. Table 1. lists measurements of populations sampled at various localities in the United States. The measurements from South Carolina and California were taken from Raski and Golden (1965) and those from South Dakota were from Thorne and Malek (1968).
The most variable characteristics are stylet length and number of annules. Specimens from Iowa represent the most variant populations. The stylet length of 68 to 78 um is the shortest known to date and the annules number of 64 to 70 has been the least recorded (Table 1). Some population samples recorded from South Carolina, South Dakota, and California have greater values for these characters. Populations from the latter three states do not differ from each other as much as they differ from the Iowa populations (Table 1).
Table 1. Variation in taxonomic characters of Criconemoides permistus from different localities.
L um Stylet um V % Rv R Rex Iowa 233-390 68-78 82.9 - 91.7 11-14 64-70 20-24 South Carolina paratypes
L. Meares pond
84.0 - 88.0
85.0 - 87.0
85.0 - 87.0
California 270-360 87-102 83.0 - 87.0 * 77-87 * South Dakota 400 100 85.0 12 90-100 * * Data not available
(Description- Hoffman, 1974)
This genus included in the Criconematid Project