Mesocriconema sphaerocephalum
(Taylor, 1936) Loof & De Grisse, 1989
Syn.: Criconemoides sphaerocephalus Taylor, 1936
Macroposthonia sphaerocephala (Taylor, 1936) De Grisse & Loof, 1965
Criconemella sphaerocephala (Taylor, 1936) Luc & Raski, 1981
Criconemoides citri Steiner, 1949
Macroposthonia citri (Steiner, 1949) Siddiqi, 1986
Criconemoides georgii Prasad, Khan & Mathur, 1966
Macroposthonia georgii (Prasad, Khan & Mathur, 1966) Siddiqi, 1986

Photo Gallery:
Spring Creek Prairie, NE
Length, 0.3 mm; a = 9-10.  Tail rounded.  Head of two annules set off from body annules only by being narrower and rounded rather than retrorse.  Head contour rounded.  Mouth opening minute.  Annules 68-72, difficult to count exactly as they "break joint" along lateral line, forming a zig-zag line there.  Anterior portion of oesophagus not much swollen by spear muscles.  Middle oesophageal bulb very large, almost as wide as body cavity.  Short isthmus surrounded by nerve ring.  Terminal bulb subglobular.  Stylet 57um long, extending through 14 annules, very stout.  Stylet base more than 1/3 as wide as neck, resting just in front of center of middle oesophageal bulb.  Anus at next to last annule.  Conspicuous vulva at 4th or 5th annule in front of terminus, opening often more or less gaping.  Vagina about half as long as body width.  Size of egg 72u x 24u.  One egg completely filling uterus.  Ovary cylindrical, then tapering, with blind end somewhat behind base of oesophagus.  Oocytes numerous, irregularly arranged.  Male unknown, none among 20 specimens.

Habitat:  Soil around roots of a grass, Island of Trinidad, British West Indies.
(Description- Taylor, 1936)