Malenchus geraerti

Contents

Rev 04/03/2023

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Refer to subfamily diagnosis (Tylenchinae)

• Body slightly ventrally curved, narrowing from the level of vulva to tail.

• Cuticle coarsely annulated, annuli 2.1–2.3 µm wide at mid-body.

• Lateral field a plain band with two incisures, raised in cross section.

•  Lip region continuous with body contour, with bearing 3–4 annuli.

• Amphidial openings S-shaped slits, starting from labial plate, extending posteriorly, markedly narrowing and reaching base of the head.

• Cephalic framework weakly sclerotized.

• Stylet shaft moderately developed, conus finer, knobs directed posteriorly.

• Dorsal gland orifice (DEGO) close to stylet knobs.

• Excretory pore at level of esophageal bulb.

• Esophagus with slender procorpus, muscular, rounded to ellipsoid metacorpus with well-developed valve, slender isthmus and saccate pharyngeal bulb .

•  Tail in both sexes conical, tapering gradually to a more or less pointed tip.



Females:

• Mono-prodelphic, ovary outstretched, oocytes mostly in single file, oviduct short, spermatheca elongate-rounded, filled with small spheroid sperm cells, offset and sometimes appearing as bilobed  crustaformeria and uterus not clearly discernible from each other.
• Vagina perpendicular to body axis, with moderately sclerotized walls.
• Small, undifferentiated postvulval uterine sac (PUS) present.
• Vulva sunken into body,  a transverse slit, with large epiptygma and no flaps.
• Vulva–anus distance  0.8–1.1 times the tail length.

Males:  

•  About half as frequent as females.
•  Testis single, outstretched.
• Spicules tylenchoid, narrow and slender, slightly arcuate distally.
•  Gubernaculum small.
•  Bursa cloacal with smooth margin.

Ref: Pedram et al., 2018

Reported median body size for this species (Length mm; width micrometers; weight micrograms) - Click: