Amphid

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Amphids (Greek: amphi, around, double) are innervated invaginations of cuticle in nematodes. They are usually found in the anterior (head) region of the animal, at the base of the lips. Amphids are the principal olfactosensory organs of nematodes. Each amphid is made up of 12 sensory neurons with ciliated dendrites.

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Northern root-knot nematode is a species of vegetable pathogens which produces tiny galls on around 550 crop and weed species. They invade root tissue after birth. Females are able to lay up to 1,000 eggs at a time in a large egg mass. By surviving harsh winters, they can survive in cold climates.

Enoplea Class of roundworms

Enoplea (enopleans) is a class, which with the classes Secernentea and Chromadorea make up the phylum Nematoda in current taxonomy. The Enoplea are considered to be a more ancestral group than the Chromadorea, and researchers have referred to its members as the "ancestrally diverged nematodes", compared to the "more recently diverged nematodes" of Chromadorea.

Rhabditia Subclass of roundworms

Subclass Rhabditia is mostly composed of parasitic nematodes, though there are some free-living species as well. Phasmids are well-developed, while amphids are poorly developed or absent in this group.

Secernentea Class of roundworms

Secernentea was a class of nematodes in the Classical Phylogeny System and is no longer in use. This morphological-based classification system has been replaced by the Modern Phylogeny system, where taxonomy assignment is based on small subunit ribosomal DNA.

Chromadorea Class of roundworms

The Chromadorea are a class of the roundworm phylum, Nematoda. They contain a single subclass (Chromadoria) and several orders. With such a redundant arrangement, the Chromadoria are liable to be divided if the orders are found to form several clades, or abandoned if they are found to constitute a single radiation.

Belonolaimus longicaudatus is a common parasite of grasses and other plant crops and products. It is the most destructive nematode pest of turf grass, and it also attacks a wide range of fruit, vegetable, and fiber crops such as citrus, cotton, ornamentals, and forage. The sting nematode is a migratory ectoparasite of roots. It is well established in many golf courses and presents a problem in turf management. The sting nematode is only present in very sandy soils. It cannot reproduce in heavier or clay soils.

<i>Pratylenchus penetrans</i> Species of roundworm

Pratylenchus penetrans is a species of nematode in the genus Pratylenchus, the lesion nematodes. It occurs in temperate regions worldwide, regions between the subtropics and the polar circles. It is an animal that inhabits the roots of a wide variety of plants and results in necrotic lesions on the roots. Symptoms of P. penetrans make it hard to distinguish from other plant pathogens; only an assay of soil can conclusively diagnose a nematode problem in the field. P. penetrans is physically very similar to other nematode species, but is characterized by its highly distinctive mouthpiece. P. penetrans uses its highly modified mouth organs to rupture the outer surface of subterranean plant root structures. It will then enter into the root interior and feed on the plant tissue inside. P. penetrans is considered to be a crop parasite and farmers will often treat their soil with various pesticides in an attempt to eliminate the damage caused by an infestation. In doing this, farmers will also eliminate many of the beneficial soil fauna, which will lead to an overall degradation of soil quality in the future. Alternative, more environmentally sustainable methods to control P. penetrans populations may be possible in certain regions.

Xiphinema diversicaudatum is an amphimictic ectoparasitic nematode species. This species has a characteristically long stylet capable of penetrating into a host’s vascular tissue. They have a wide host range with some of the extensively studied ones being strawberry, hops and raspberry, due to their economic importance. The direct root damage caused through penetration near the root tip and formation of galls is a secondary concern when compared with the damage caused by vectoring the arabis mosaic virus. The virus attaches to the interior cuticle lining and can be transferred from infected to uninfected root tissue as the nematode feeds and sheds. Management of this particular nematode relies on nematicides such as 1,3-Dichloropropene (Telone) at 40 gpa.or methyl bromide at 1000 lb/ac to control to 28 in deep.

Tylenchorhynchus is a genus of nematodes including many species of plant parasites. The classification of stunt nematodes - those including the genus Tylenchorhynchus - is unstable; many newly discovered species within this genus are reconsidered to be actually subspecies. Stunt nematodes such as Tylenchorhynchus and the closely related genera, Anguillulina and Merlinia, include more than 250 known species. Members of these genera possess similar anatomy and may be easily mistaken for one another. Some debate has led to the classification of single species under different names in two distinct genera.

Nematode Phylum of worms with tubular digestive systems with openings at both ends

The nematodes or roundworms constitute the phylum Nematoda, with plant-parasitic nematodes also known as eelworms. They are a diverse animal phylum inhabiting a broad range of environments. Taxonomically, they are classified along with insects and other moulting animals in the clade Ecdysozoa, and unlike flatworms, have tubular digestive systems with openings at both ends. Like tardigrades, they have a reduced number of Hox genes, but their sister phylum Nematomorpha has kept the ancestral protostome Hox genotype, which shows that the reduction has occurred within the nematode phylum.

Phasmids are unicellular sensilla in the lateral tail region of certain species of nematodes. They are similar in their structure to amphid sensilla, but smaller. Phasmid neurons were recently shown to function in modulation of chemorepulsion behavior.

The red ring disease of coconuts and African oil palms is caused by the nematode Bursaphelenchus cocophilus. It is also identified in literature with an alternative scientific name Rhadinaphelenchus cocophilus. The common name, the red ring nematode, is derived from its distinguishing symptom.

Anthelmintic Antiparasitic drugs that expel parasitic worms (helminths) from the body

Anthelmintics or antihelminthics are a group of antiparasitic drugs that expel parasitic worms (helminths) and other internal parasites from the body by either stunning or killing them and without causing significant damage to the host. They may also be called vermifuges or vermicides. Anthelmintics are used to treat people who are infected by helminths, a condition called helminthiasis. These drugs are also used to treat infected animals.

Myleusnema bicornis is an intestinal parasite of Myleus ternetzi, or "Ternetz's Silver Dollar", a freshwater Characoid fish commonly found in the French Guiana river. M. bicornis has several unusual morphological characteristics, namely the two postcloacal "horns" in the posterior of males, and a separate elongated cephalic region (head) that may be extended and retracted. These features differ vastly from other Cosmocercoidean nematodes, as well as any others within the family Kathlaniidae, and as such necessitate the creation of the new genus Myleusnema; however, no genetic taxonomic studies have been performed.

Durikainema is a genus of two nematodes in the family Robertdollfusiidae. Species have a head with a cuticular cephalic inflation, elongated papillae and amphids, and well-developed musculature. Characteristics of the males include a single spicule and a long attenuated tail. Durikainema species parasitize macropods. The genus was circumscribed in 1982 with the type species Durikainema macropi, a parasite of the eastern grey kangaroo. D. phascolarcti, parasite of the koala, was described in 1998.

Anguillicoloides papernai is a parasitic nematode worm that lives in the swimbladders of eels, particularly Anguilla mossambica. Specimens have been located in Cape Province, South Africa. It is named after Dr. Ilan Paperna. What differentiates this species from its congeners is the presence of marked cuticular excrescences on the anterior and posterior ends of the body and the location of the buccal capsule deeply inside the head end. This species was the first Anguillicola member described from Africa.

Enoplia Subclass of roundworms

The Enoplia are a subclass of nematodes in the class Enoplea.

Dirofilaria tenuis is a species of nematode, a parasitic roundworm that infects the subcutaneous tissue of vertebrates. D. tenuis most commonly infects raccoons, but some human cases have been reported. They are vectored by mosquitoes and follow similar development and transmission patterns as other Dirofilaria.

Philometra priacanthi is a species of parasitic nematode of fishes. Its name is derived from its host species, Priacanthus hamrur. It possesses dorsal lamella-like structures on the distal part of its gubernaculum, which can also be found on other of its cogenerates. The only species with a dorsal protuberance near the gubernaculum's end is P. priacanthi, however. P. lateolabracis can be distinguished from the former by the lateral caudal mounds separated dorsally, narrower lamella-like structures on its gubernaculum, shorter spicules, and by the testis extending anteriorly. Other gonad-infecting species differ from this one by possessing a smooth gubernaculum, and their spicules being of different lengths. Seven gonad-infecting species of Philometra can be distinguished from P. priacanthi by their host types, as well as by geographical distribution.

Mononchoides fortidens, of the order Diplogasterida, is a free-living predacious nematode that feeds on both nematodes and bacteria . The predatory behavior of this nematode presents the opportunity to use it as a bio-control agent against other plant parasitic nematodes. It has been shown to have a preference for the second stage juveniles of Meloidogyne incognita.

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