The ''Trichosomoididae'' is a
family
Family (from la, familia) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its ...
of
nematode
The nematodes ( or grc-gre, Νηματώδη; la, Nematoda) or roundworms constitute the phylum Nematoda (also called Nemathelminthes), with plant-Parasitism, parasitic nematodes also known as eelworms. They are a diverse animal phylum inhab ...
s.
Morphological characteristics
The Trichosomoididae, as most nematodes, have an elongate body, vermiform and covered with a
cuticle
A cuticle (), or cuticula, is any of a variety of tough but flexible, non-mineral outer coverings of an organism, or parts of an organism, that provide protection. Various types of "cuticle" are non- homologous, differing in their origin, structu ...
. There is often a cuticular ornamentation in form of cephalic vesicles or bosses. They are 'aphasmidian' nematodes, i.e. they have no phasmids.
The Trichosomoididae are small, with sometimes a marked sexual
dimorphism, the female being larger than the male. In some cases, the male lives permanently or penetrates deeply in the female uterus. The body is slightly thicker in the posterior end.
The anterior part of the oesophagus is short, its posterior part is surrounded by glandular cells called
stichocyte
Stichocytes are glandular unicellular cells arranged in a row along the posterior portion of the oesophagus, each of which communicates by a single pore with the lumen of the oesophagus. They contain mitochondria, rough endoplasmic reticulum, abund ...
s, arranged in chain.
The
spicule
Spicules are any of various small needle-like anatomical structures occurring in organisms
Spicule may also refer to:
*Spicule (sponge), small skeletal elements of sea sponges
*Spicule (nematode), reproductive structures found in male nematodes ( ...
and spicular sheath are absent or vestigial in the male.
The female has its vulva near the end of the oesophagus and its anus is terminal. Females are
oviparous
Oviparous animals are animals that lay their eggs, with little or no other embryonic development within the mother. This is the reproductive method of most fish, amphibians, most reptiles, and all pterosaurs, dinosaurs (including birds), and ...
; eggs are thick-shelled, with plugs on both poles. Eggs are embryonated when laid or laid at very early stage with incompletely developed shells.
Biology
![Huffmanela hamo eggs (Microscope) 1D](https://upload.wikimedia.org/wikipedia/commons/e/ef/Huffmanela_hamo_eggs_%28Microscope%29_1D.JPG)
Nematodes of the family Trichosomoididae are all
parasite
Parasitism is a close relationship between species, where one organism, the parasite, lives on or inside another organism, the host, causing it some harm, and is adapted structurally to this way of life. The entomologist E. O. Wilson has ...
s
of various
tissues (
mucosa
A mucous membrane or mucosa is a membrane that lines various cavities in the body of an organism and covers the surface of internal organs. It consists of one or more layers of epithelial cells overlying a layer of loose connective tissue. It is ...
, paracloacal glands,
cornea
The cornea is the transparent front part of the eye that covers the iris, pupil, and anterior chamber. Along with the anterior chamber and lens, the cornea refracts light, accounting for approximately two-thirds of the eye's total optical power ...
,
musculature
Skeletal muscles (commonly referred to as muscles) are organs of the vertebrate muscular system and typically are attached by tendons to bones of a skeleton. The muscle cells of skeletal muscles are much longer than in the other types of muscle ...
,
swimbladder
The swim bladder, gas bladder, fish maw, or air bladder is an internal gas-filled organ that contributes to the ability of many bony fish (but not cartilaginous fish) to control their buoyancy, and thus to stay at their current water depth w ...
wall) and even
bone
A bone is a Stiffness, rigid Organ (biology), organ that constitutes part of the skeleton in most vertebrate animals. Bones protect the various other organs of the body, produce red blood cell, red and white blood cells, store minerals, provid ...
s of
fish
Fish are aquatic, craniate, gill-bearing animals that lack limbs with digits. Included in this definition are the living hagfish, lampreys, and cartilaginous and bony fish as well as various extinct related groups. Approximately 95% of li ...
es and
mammals
Mammals () are a group of vertebrate animals constituting the class Mammalia (), characterized by the presence of mammary glands which in females produce milk for feeding (nursing) their young, a neocortex (a region of the brain), fur or ...
.
Classification
According to
Moravec(2001)
[Moravec, František. Trichinelloid Nematodes parasitic in cold-blooded vertebrates. Academia, Praha ()]
, the family Trichosomoididae Hall, 1916
[Hall, M.C. 1916: Nematode parasites of mammals of the orders Rodentia, Lagomorpha and Hyracoidea. Proceedings of the U.S. National Museum, 50, 1–24]
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includes
* Subfamily Anatrichosomatinae Smith & Chitwood, 1954
** Genus ''
Anatrichosoma'' Smith & Chitwood, 1954
* Subfamily Huffmanelinae
Moravec, 2001 (Tissue parasites of fishes)
** Genus ''
Huffmanela
''Huffmanela'' is a genus of parasitic nematodes, belonging to the family Trichosomoididae.
Morphology
As other nematodes, species of ''Huffmanela'' are elongate and vermiform. They are especially thin and small. The male is smaller than the fem ...
''
Moravec, 1987
* Subfamily Trichosomoidinae Hall, 1916
** Genus ''
Trichosomoides''
Railliet
Louis-Joseph Alcide Railliet (also known as Alcide Railliet, born 11 March 1852 at La Neuville-lès-Wasigny in the Ardennes – died 25 December 1930) was a French veterinarian and helminthologist.
Professor at the Veterinary School of Alfort, ...
, 1895
** Genus ''
Trichuroides'' Ricci, 1949
References
External links
{{Taxonbar, from=Q7840997
Trichocephalida