Classification:

Class:    Chromadorea

Subclass: Chromadoria

Order:   Rhabditida 

           Suborder: Spirurina

Superfamily: Ascaridoidea

Family:  Ascarididae

     Seuratascaris numidica (Seurat, 1917) Sprent, 1985

Type species of the genus:

Synonym:

 

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Morphology and Anatomy:

Seuratascaris numidica is the only species of the genus. Sprent (1985) re-examined specimens of S. numidica collected from different geographical locations and found  considerable morphological variability with regard to the cephalic extremity, body lengths, esophagus, intestine, spicules and the number and arrangement of caudal papillae..

Due to lack of genetic data it remains unclear whether S. numidica represents a species complex or is a aingle species.

Nematodes with general characteristics of Ascarididae, and:

• Small-sized nematodes, whitish when alive.
•  Cuticle with fine, transverse striations.
•  Anterior extremity with 3 nearly trapeziform lips; distal part of each lip with small, triangular, medio-apical notch; dorsal lip with one pair of large double cephalic papillae; subventral lips each with one doublecephalic papilla, small papilla and amphid
• Lips with distal ridge armed with 64-76 well-developed conical denticles
• Lateral alae absent.
• Esophagus muscular, long, posterior part almost as wide as anterior.
• Nerve-ring at about 18% of esophageal length; excretory pore at level of nerve-ring.
• Tail of both sexes conical, with small digitiform tip

Ref: Chen et al., 2018

Males:

• Spicules robust, without alae,  almost equal length, blunt at distal end, 1% of body length
• Gubernaculum absent.
• Caudal papillae 8-9 pairs in total,  4 pairs precloacal and 4-5 pairs postcloacal
• Single medio-ventral precloacal papilla anterior to precloacal lip

Females:

• Didelphic
• Vulva slit-like, situated about 29.5% of body length; vagina muscular.
• Tail 190 um long, lateral phasmids present

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