Xyo pseudohystrix

Xyo pseudohystrix	Contents	Rev 03/06/2023
	Classification	Biology and Ecology
	Morphology and Anatomy	Life Cycle
Return to Xyo Menu		Ecosystem Functions and Services
	Distribution	Management
Return to Hystrignathidae Menu	Feeding	References
	Go to Nemaplex Main Menu	Go to Dictionary of Terminology

Classification:

Rhabditida
Spirurina
Thelastomatoidea: Hystrignathidae

Xyo pseudohystrix Travassos & Kloss, 1958

Morphology and Anatomy:

Body comparatively robust, widening gradually posterior to head, reaching its maximum width at level of the vulva.
Sub-cuticular striae present.
Cervical cuticle with alternate rows of spines, from the base of the annulated region to ca. one body-width posterior to the basal bulb. After the first row the spines become larger and then start to diminish in size
Lateral alae absent. Lateral gap present in the spiny region.
Head with eight paired, rounded and flattened cephalic papillae, their diameter of ca. 3 um.
Cephalic papillae with a central depression, its diameter of ca. 2 um.
Oral opening surrounded by a cuticular, prominent annular lip, not in contact with the cephalic papillae.
Amphids lateral, their opening triradiate and located at a small protuberance at level of the external edges of the cephalic papillae.
Stoma with triradiate lumen, surrounded by an esophageal collar.
Esophagus with muscular, sub-cylindrical procorpus, cylindrical isthmus and basal bulb rounded, with valve-plate well-developed.
Nerve ring encircling procorpus at its midpoint.
Excretory pore ventral, located at ca. two body-widths posterior to the basal bulb.
Intestine simple, sub-rectilinear, its fore region dilated. Rectum short.
Anus a crescent-like ventromedian transverse slit. Nerve ring encircling procorpus at ca. its midpoint. Excretory pore ventral, located at ca. two body-widths posterior to the basal bulb.
Tail conical and attenuate, ending in a sharp tip.

Ref: Morffe et al., 2019.


	Xyo pseudohystrix. D: anterior region, face view; E: anterior region, lateral view. Scale bar D = 30um; scale bar E = 50um Scanning electron micropgraph adapted from Morffe et al., 2019.
Male:	Female: Vulva a median transverse slit its lips barely prominent, located near the midbody. Vagina muscular, forwardly directed. Genital tract didelphic-amphidelphic, both ovaries reflexed. Distal end of the anterior ovary reflexed at the level of the excretory pore, distal flexure ca. two body-widths long. Distal end of the posterior ovary reflexed at ca. 2.5 body-widths anterior to the level of the anus, Oocytes in single rows. Fusiform spermatheca present in the posterior uterus, near the level of the basal end of the anterior ovary but spermatheca absent in the anterior branch of the genital tract. Eggs ellipsoidal, smooth-shelled and numerous
Reported median body size for this species (Length mm; width micrometers; weight micrograms) - Click:strong>

Distribution:

Reported from host beetles, Odontotaenius disjunctus, from Ohio and Georgia, USA (Morffe et al., 2019).

Feeding:

Intestinal parasites of passalid beetles (Coleoptera).

Life Cycle:

Ecophysiological Parameters:

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

Ecosystem Functions and Services:

Morffe, J., Garcia, N., Davus, A.K., Hasegawa, K., Carreno, R.A. 2019. Morphological and molecular characterization of Xyo pseudohystrix Travassos & Kloss, 1958 (Nematoda: Oxyuridomorpha: Hystrignathidae) from Odontotaenius disjunctus (Illiger, 1800) (Coleoptera: Passalidae) from USA and discussion on its taxonomic status. Zootaxa 4619:391-400