Contribution � la connaissance de la faune parasitaire d' Argentine, XV. Etude morphologique de Heteroxynema (Cavioxyura) viscaciae n. sp. (Nematoda, Heteroxynematidae) parasite de Lagidium viscacia boxi (Mammalia, Rodentia)

Abstract

R&urn6Heteroxynema (Cavioxyura) viscaciae n. sp., parasite du caecum et du gros intestin d' un rongeur caviomorphe d' Argentine, Lagidium viscacia boxiThomas, est dbcrit. Cette nouvelle espece est tres proche de Heteroxynema (Cavioxyura) chiliensis Quentin, 1975, parasite d' octodon degus (Molina) au Chili, dont elle se distingue essentiellement par ses mensurations et par la disposition de certaines papilles genitales des males. L' etude de cette nouvelle espbce montre l' existence: (i) au niveau des structures buccales d' un dimorphisme sexuel d' un type peu frequent chez les Oxyuroidea; (ii) de quatre paires seulement de papilles genitales males voisinant avec des reliefs cuticulaires qui, dans d' autres espbces, ont peut-etre CtC confondus avec des terminaisons nerveuses supplementaires; (iii) d' un gubernaculum et d' un spicule, organes rarement observes chez les Heteroxynematidae, mais dont la presence dans d' autres especes du groupe pourrait avoir CtC ignoree; (iv) au niveau de l' odjecteur, d' un sphincter particulierement differencie et developpe. ResumenSe describe a Heteroxynema (Cavioxyura) viscaciae n. sp. parasite de1 ciego intestino grueso de1 rodeor Lagidium viscacia boxi Thomas. Esta nueva especie se asemeja a Heteroxynema (Cavioxyura) chiliensis Quentin, 1975, parasite de Octodon degus (Molina) de Chile de la cual se diferencie esencialmente por sus medidas y por la disposition de las papilas genitales de1 macho. El estudio de esta nueva especie muestra la existencia de: (i) un tipo poco frecuente en 10s Oxyuroidea de dimorfismo sexual a nivel de las estructuras bucales; (ii) cuatro pares de papilas genitales en el macho ubicadas proximas a relieves cuticulares que en otras especies pueden haber sido confundidos con terminaciones nerviosas suplementarias; (iii) de un gubernaculo y una espicula, organos raramente observables en 10s Heteroxynematidae, pero cuya presencia en otras especies de1 grupo pudo haber sido ignorada; (iv) de un sphincter particularmente diferenciado y desarollado. J.P. Hugot et C.A. Sutton AbstractHeteroxynema (Cavioxyura) viscaciae n. sp., parasitic in the caecum and large intestine of Lagidium viscacia boxi Thomas, is described. The most closely related species is Heteroxynema (Cavioxyura) chiliensis Quentin, 1975, a parasite of Octodon degus (Molina) from Chile, from which the new species differs by its measurements and disposition of the male's genital papillae. Study of this new species shows the existence of: (i) a type of sexual dimorphism infrequent in the Oxyuroidea, at the level of the buccal structures; (ii) only four pairs of male genital papillae adjoining cuticular protuberances which in other species may have been confused with supplementary nerve endings; (iii) a gubernaculum and a spicule, structures infrequently observed in the Heteroxynematidae, and possibly overlooked or ignored in other species; (iv) a sphincter which is strongly differentiated and developed.

A palaeoparasitological analysis of rodent coprolites from the Cueva Huenul 1 archaeological site in Patagonia (Argentina)

“…Based on the characteristics of the eggs of the parasites found in this study and on knowledge regarding the parasite fauna of modern viscachas, the faeces were ten- tatively attributed to L. viscacia (Caviomorpha: Chinchillidae) (Hugot & Sutton 1989, Denegri et al 2003.…”

“…In Argentina, Teixeira de Freitas and Lins de Almeida (1936) ciae was described by Sutton and Hugot (1989) from L. viscaciae collected from Chubut Province. Foster et al (2002) and Ferreira et al (2007) confirmed the presence of this parasite in wild viscacha Lagostomus maximus from La Pampa and Chaco Provinces.…”

“…and H. viscaciae, respectively. Hugot and Sutton (1989) stated that the species related most closely to H. viscaciae is Heteroxynema (Cavioxyura) chiliensis Quentin, 1975, a parasite of Octodon degus (Molina) from Chile. Perkins et al (2005) stated that rodents represent one of the most important sources of zoonoses for mammals and that increases in the population densities of rodents resulted in the dispersal of zoonoses and brought them into closer contact with humans.…”

Lamotheoxyuris ackerti n. gen., n. comb. (Nematoda: Heteroxynematidae) parasite of Neotoma spp. (Rodentia: Muridae)

“…However, the new genus differs from all these genera by the following main characteristics: Dermatopallarya have three lips and a defined buccal cavity instead of six lips and a mouth opening directly to the esophagus, as in the new genus; in addition, males of Dermatopallarya possess two ventral cuticular swellings, which are absent in the new genus (Petter & Quentin 1976, Skrjabin 1982; the esophageal bulb in Fastigiuris is reduced or absent whereas this structure is well developed in the new genus; also, the cervical alae in Fastigiuris are markedly bent in the ventral region (Petter & Quentin 1976) while the cervical alae are straight in the specimens described in this study. Likewise, Lamotheoxyuris can be differentiated from Heteroxynema because males of this later genus have a precloacal pseudosucker, gubernaculum, and a spicule (Petter & Quentin 1976, Hugot & Sutton 1989, which are all lacking in the new genus. Ivaschkinonema possesses four differentiated lips and caudal rings (Erkulov 1975), whereas Lamotheoxyuris has six lips and lacks caudal rings.…”

Nematodes oxyuridae, trichuridae y capillariidae en roedores akodontini (Cricetidae: sigmodontinae) de la cuenca del Plata, Argentina: su importancia en la interpretación de las relaciones parásito-hospedador-ambiente

“…En Argentina, alrededor de cinco especies de Oxyuridae han sido encontradas en roedores (Sutton, 1978;Hugot y Sutton, 1989;Sutton y Hugot, 1993). Mientras que especies de Trichuridae y Capillariidae han sido halladas en humanos, aves y peces (Digiani, 1999;Carballo y Navone, 2007), pocas especies se han registrado en mamíferos y entre los roedores sólo puede mencionarse la presencia de una especie parásita en un sigmodontino de la tribu akodontini (Suriano y Navone, 1994;Navone et al, en prensa).…”