Angiostoma margaretae

Angiostoma margaretae	Contents	Rev 03/09/2024
	Classification	Biology and Ecology
	Morphology and Anatomy	Life Cycle
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Rhabditoidea

Angiostomatidae

Angiostoma margaretae Ross, Malan & Ivanova (2011)

Synonyms:

Morphology and Anatomy:

No sexual dimorphism
Body slightly tapered towards anterior end.
Short conical tail with bluntly rounded tip
Cuticle 1â€“2 um thick, clearly annulated and longitudinally striated. Lateral alae present.
Head bluntly rounded with 6 low lips around mouth aperture, each bearing bristle-like sensilla cof external circle and shorter sensilla of internal circle.
Amphids pore-like on ventrolateral lips.
Mouth opening circular, c.9-12 um wide. Stoma spacious, bowl-shaped. Walls thickly cuticularised, nearly straight inside and convex outside, with maximum width below mid-stoma.
Three prominent, isomorphic, triangular, distally rounded flaps forming posterior portion of stoma.
Arcade cells at level of posterior third of stoma.
Pharynx stout, muscular, club-shaped, comprises corpus which is slightly swollen anteriorly and occupies half pharyngeal length, isthmus which is only slightly narrower than posterior of region corpus, and valvate bulb not wider than corpus.
Nerve-ring crosses isthmus. Cardia prominent, comprised of 2 cells.
Intestine well developed, with thick walls. Rectal glands enlarged.

Female:

Lateral alae prominent, extend from anterior to pharynx almost to tip of tail.
Didelphic, amphidelphic; uteri divergent. Ovaries long, outstretched distally almost reaching pharyngeal base; posteriormost cell of posterior ovary almost reaches anus.
Each genital tube forms 2 coils at mid-distance between vulva and their distal extremities. Coiled oviducts separated from uteri by sphincters.
Uteri contain c.60 eggs at different stages of development and c.20â€“30 larvae with equal numbers in each branch.
Vulva slit-like. Vulva lips only slightly inflated.
Rectum cuticularised.
Tail conical, with rounded tip

Male:

Lateral alae start just posterior to base of stoma and end anterior to cloaca;
Monorchic. Testis length nearly equal to body length.
Spermatids large, grain-like,
Tail short, initially widely conical, then tapering to bluntly rounded tip.
Spicules equal, well cuticularized, with short, distinct manubria. Velum extends from proximal part of shaft to mid-shaft level.
Gubernaculum about 3 times shorter than spicule, very slightly curved,
Bursa narrow, open, extends from mid-spicule level to end of initial, wider region of tail.
Seven pairs of pedunculate papillae
Phasmid located at beginning of narrower region of tail,

Ref: Ross et al., 2011

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

Distribution:

Described from South Africa

Feeding:

Gastro-intestinal parasite of a slug. Obseved in the esophagus of the slug, Milax gagates, in Western Cape Province, South Africa.

Angiostoma margaretae is morphologically similar to A. milacis Ivanova & Wilson, 2009, reported from a slug of the genus Milax in Britain. Ross et al (2011) hypothesize differences between the species may have occurred since geographic isolation of Milax gagates, and its parasites, with the arrival of European settlers in South Africa during the 18th and 19th Centuries.

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Life Cycle:

Ecophysiological Parameters:

For Ecophysiological Parameters for this species, click	If species level data are not available, click for genus level parameters