Ancylostomatoidea

Superfamily: Ancylostomatoidea

Revised 04/05/24

Classification:


Chromadorea: Chromadoria
Rhabditida: Rhabditina
Infraorder Rhabditomorpha
Ancylostomatoidea (Looss, 1905) Chabaud, 1965

Hookworms

Name derived from "ancylo" = hook and "stoma" = opening (as in mouth)

Morphology and Anatomy:

Small to medium-sized, thick-bodied, bursate nematodes
The large, globular, dorsally orientated buccal capsules of the Ancylostomatoidea are devoid of both lips and corona radiata.
In classification schemes based on characteristics of the buccal capsule, the Ancylostomatoidea have sometimes been grouped with the Strongyloidea because both superfamilies have large globular buccal capsules (Yorke & Maplestone, 1926; Chitwood, 1969). Both Dougherty (1951) and Schulz (1952), however, emphasized the presence in the Ancylostomatoidea of an ovejector of the trichostrongyloid type and concluded that the Ancylostomatoidea are more closely related to the Trichostrongyloidea than to the Strongyloidea.
The Ancylostomatoidea also resemble the Trichostrongyloidea·in characteristics of the life-cycle, copulatory bursa and female tail, and in that both superfamilies are parasitic in the small intestine rather than the large, where most of the Strongyloidea are found.
Chabaud (1965, 1974) described the Ancylostomatoidea as follows: "Buccal capsule sub-globular, never hexagonal in transverse section. Lips and corona radiata absent. Oral opening unarmed or with teeth and cutting plates." This broad definition of the superfamily (closely following Dougherty, 1951) accommodates several genera without cutting plates or with reduced cutting plates in the oral opening, and it is accepted herein as the definition of the Ancylostomatoidea

Ref Lichtenfels, 1980

Distribution

Economic Importance:

Hookworms are considered one of the most common groups of soil-transmitted nematode parasites of vertebrates.
They cause causing serious iron-deficiency anemia and protein malnutrition in humans and domestic and wild mammals.
Two of the major genera, Ancylostoma and Necator, are responsible for considerable morbidity and socioeconomic burdens in humans.

Of these two genera, Ancylostoma hookworms are considered to be of greater medical and veterinary importance because of distribution, prevalence, and the abundance of zoonotic species.

The human-infecting ‘anthrophilic’ hookworm is represnted by Ancylostoma duodenale (Dubini, 1843).

Many other species are considered ‘anthropozoonotic’ forms, capable of infecting and circulating among free-ranging wild hosts, some domestic hosts and humans. They include Ancylostoma caninum (Ercolani, 1859), Ancylostoma braziliense Gomes de Faria, 1910 and Ancylostoma ceylanicum Looss, 1911.

About 35 other species of Ancylostoma represent the considerable diversity of the genus and are considered to be primarily of veterinary importance. Many host species are carnivores (Xie et al., 2017).

Hosts:

Feeding

blood-sucking parasites of the small intestine of mammals.

Life Cycle:

Damage:

Management:

References:

Chabaud, A.G. 1965. Ordre des Strongylida. In: Grasse, P. P. Traite de Zoologie, Vol. 4, fasc. 3, pp. 869-933.

Chabaud, A.G. 1974. Keys to subclasses, orders and superfamilies. In R. C. Anderson, A. G.Chabaud, and S. Willmott (eds.), CIH keys to the nematode parasites of vertebrates, No. 1, pp. 6-17. Commonwealth Agricultural Bureaux, England.

Chitwood, M.B. 1969. The systematica and biology of some parasitic nematodes. In Florkin, M. and Scheer, B.T. (eds) Chemical Zoology III Echinodermata, Nematoda and Acanthocephala. Academic Press pp223-244

Dougherty, E.C. 1951. Evolution of zooparasitic groups in the phylum Nematoda, with special reference to host distribution. J. Parasit. 37:353-378.

Lichtenfels, J.R. 1979. A conventional approach to a new classification of the Strongyloidea, nematode parasites of mammala. Amer. Zool. (1979): 1185-1194

Lichtenfels, J.R. 1980. CIH keys to the nematode parasites of vertebrates. No. 8. Keys to genera of the superfamilies Ancylostomatoides,and Diaphanocephaloidea. Commonwealth Agricultural Bureaux, Farnham Royal, Bucks, England

Schulz, R.S. 1952. Phytogeny of strongylates. In K. I. Skrjabin (ed.), Key to parasitic nematodes, Vol. 3, Strongylata, pp. 13-20. Akad. Nauk SSSR, Moscow. (English translation, 1961, N.T.I.S., U.S Dept. Com- merce, Springfield, Va., USA.)

Xie, Y., Hoberg, E.P., Yang, Z., Urban Jr, J.F. and Yang, G. 2017. Ancylostoma ailuropodae n. sp. (Nematoda: Ancylostomatidae), a new hookworm parasite isolated from wild giant pandas in Southwest China. Parasites and Vectors 10:217.

Yorke, W. and Maplestone, P.A. 1926. The Nematode Parasites of Vertebrates. Churchill, London

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Recent Clessification	Alternative Classification	Relationships among species, genera, and even families, within the Nematoda are becoming clearer as morphological, morphometric, and life history features are considered along with molecular-based phylogenies. However, there remain differences of opinion among experts regarding classifications above the family level. Such differences are apparent in the classification in the Order Strongylida or the consideration of suborders of the Strongylida as suborders of the Rhabditida.
Rhabditida	Strongylida
Rhabditina	Ancylostomatina
Rhabditomorpha
Ancylostomatoidea	Ancylostomatoidea