Synoecnema

Synoecnema	Contents	Rev 02/10/2024
	Classification	Hosts
	Morphology and Anatomy	Life Cycle
Return to Synoecnema Menu	Economic Importance	Damage
	Distribution	Management
Return to Ungellidae Menu	Feeding	References
	Go to Nemaplex Main Menu	Go to Dictionary of Terminology

Classification:

Rhabditida Tylenchina Drilonematoidea
Ungellidae: Synoecneminae

Synoecnema de Magalhaes, 1905

Type species of the genus: Synoecnema fragile de Magalhaes, 1905

Synonyms:

Siconemalla Timm, 1967

Morphology and Anatomy:

Genus characterized by having a pair of cephalic hooks

Per description of Synoecnema hirsutum:

Body almost cylindrical, tapering to both ends.
Cuticle thin, transversely striated, with short setae and spike-like outgrowths variously distributed. No lateral fields, epidermis thick.
Anterior end curved with small paired sub-terminal cephalic hooks.
Cephalic sensilla indistinct. Amphids with apertures situated closely to hook base.
Mouth shifted ventrad; stoma absent.
Pharynx clavate with long thin muscular corpus and large muscular-glandular pear-shaped terminal bulb displaced dorsally.
Nerve ring encircling posterior of corpus.
Excretory pore 1 um wide, at level of nerve ring, excretory duct strongly cuticularised, extending beyond bulb base, paired excretory canals weakly cuticularized, passing through very large excretory gland which extends at least to mid-body.
Intestine discernible at anterior, cardia-like structure present.
Caudal organs long shallow grooves lacking cuticle, situated mid-laterally on the surface of posterior half of body.
Tail extremity conical. Sexes often permanently in copula

Female:

Prodelphic, monodelphic.
Postvulval body region very slightly swollen.
Multilobed gland of obscure function present at posterior portion of body behind vulva,
Ovary reflexedwith distal cell close to tail extremity. A large spermatheca at reflex point, filled with large spermatozoa
Vulva pre-equatorial, on slight protuberance, anterior vulval flap enlarged, No post-uterine sac.
Caudal organs extending from vulva level nearly to tail end.

Male:

Monorchic. Testis reflexed at anterior third of body level.
Spermatocytes rounded, ca. 5uï¿½m in diameter, arranged distally in two rows.
Spicular apparatus and gubernaculum absent.
Anal flaps developed unequally, anterior flap inflated and hook-like, while posterior one much smaller
No caudal sensilla detected. Caudal organ structure and position similar to that of female

Ref: Ivanova et al., 2021

Synoecnema hirsutum Timm, 1959. A. entire male; B. entire female; C. female pharynx region, D,E: female head region. F: egg. Scale bars 10 um.
Drawings from Ivanova, Efeykin, Spiridonov, 2021

Body size range for the species of this genus in the database - Click:

Distribution:

Generally described from tropical and subtropical eathworms.

Feeding:

Parasites of the body cavity of earthworms.

Hosts:

Earthworms

For an extensive host range list for this genus, click

Life Cycle:

Earthworms are the definitive and single hosts.

For Ecophysiological Parameters for this genus, click

Ivanova, E.S., Efeykin, B.D. Spiridonov, S.E. 2021. The re-description of Synoecnema hirsutum Timm, 1959 (Synoecneminae, Ungellidae, Drilonematoidea) from a pheretimoid earthworm in Vietnam with the analysis of its phylogenetic relationships ZooKeys 1076:135-190. doi: 10.3897/zookeys.1076.75932

Ivanova, E.S., Spiridonov, S.E. 1989. New species of Synoecnema (Drilonematoidea, Ungellidae) - parasitic nematodes of tropical earthworms Pheretima (Oligochaeta, Megascolecidae). In: Ryss, A Yu (Ed.). Tylenchidy i rhabditidy rasteniy i nasekomykh. Trudy Zoologicheskogo Instituta AN SSSR 194: 106-120.

Ivanova, E.S., Pham Van Luc. 1989. Synoecnema tuliemense sp.n. (Nematoda, Ungellidae) from earthworms of Vietnam. Vestnik Zoologii 3: 7-11.

Ivanova, E.S., Ganin, G.N., Spiridonov, S.E. 2014. A new genus and two new nematode species (Drilonematoidea, Ungellidae, Synoecneminae) parasitic in two morphs of Drawida ghilarovi Gates, 1969, endemic earthworm from the Russian Far East. Systematic Parasitology 87: 231-248. https://doi.org/10.1007/s11230-014-9471.

Ivanova, E.S., Sumaya, N.H., Spiridonov, S.E. 2015. Synoecnema watinagii (Drilonematoidea: Ungellidae: Synoecneminae), a new nematode species parasitic in earthworms from the Philippines with the first molecular and SEM data for the genus Zootaxa 3957: 120ï¿½130. http://dx.doi.org/10.11646/zootaxa.3957.1.10

de Magalhaes, P.S. 1905. Notes dï¿½helminthologie brasillienne. Archives de Parasitologie. Paris. 9: 305-318.

Timm, R.W 1959. Observations on Synoecnema (Nematoda, Ungellidae), with a description of two new species. Pakistan Journal of Scientific Research 11: 58-62.

Timm, R.W 1962. Nematode parasites of the coelomic cavity of earthworms. I. The genera Synoecnema and Ungella. Biologia (Dacca) 8: 1-7.

Synoecnema

Contents

Classification:

Back to Top

Morphology and Anatomy:

Back to Top

Distribution:

Back to Top

Economic Importance:

Back to Top

Feeding:

Back to Top

Hosts:

Back to Top

Life Cycle:

Back to Top

Damage:

Back to Top

Management:

Back to Top

References:

Back to Top

Copyright 1999 by Howard Ferris.
Revised: February 10, 2024.

Synoecnema

Copyright 1999 by Howard Ferris. Revised: February 10, 2024.

Copyright 1999 by Howard Ferris.
Revised: February 10, 2024.