Guerrerostrongylus marginalisn. sp. (Trichostrongyloidea: Heligmonellidae) from the Guianan arboreal mouse (Oecomys auyantepui) from French Guiana

Abstract

Based on the number and arrangement of cuticular ridges and configuration of the dorsal ray, nematode specimens collected from the small intestine of eight Guianan arboreal mice, Oecomys auyantepui (Rodentia: Sigmodontinae), in French Guiana are herein described and characterized. Guerrerostrongylus marginalis n. sp. (Heligmosomoidea: Heligmonellidae) shows a synlophe consisting of more than 40 ridges and a unique bursal arrangement with ray 8 (externo-dorsal) extending to the edge of the bursal margin, and appearing more prominent than the dorsal ray. This bursal arrangement is common in members of Hassalstrongylus Durette-Desset, 1971, but uncommon in the other four species in Guerrerostrongylus Sutton & Durette-Desset, 1991. The placement of the new species in Guerrerostrongylus is based on the number and nature of cuticular ridges and the ray arrangement and symmetry of the caudal bursa. Diagnostic characteristics of Guerrerostrongylus marginalis n. sp. include the length of ray 8 relative to bursal margin, the relative size of the spicules and vestibule, and the number of eggs in the uterus. We propose an amendment to the generic diagnosis of Guerrerostrongylus to modify the characters of the long rays 6 (postero-lateral), rays 8 (externo-dorsal), and dorsal ray as diagnostic, since at least ray 6 appears to be short in two different species in the genus, namely G. ulysi Digiani, Notarnicola & Navone, 2012 and G. marginalis n. sp.

New Species of Alippistrongylus (Trichostrongylina: Nippostrongylinae) from the Elegant Rice Rat, Euryoryzomys nitidus, of La Convención, Peru

“…Typically, the size of the spicules has been used as a diagnostic for species, since they typically are uniform in length. However, size variability is not uncommon in trichostrongylid worms, and it has been documented in the spicules of other species of South American nippostrongylines, including Guerrer-sotrongylus marginalis Weirich, Catzeflis, andJime´nez, 2016 (Weirich et al, 2016).…”

New species of Hassalstrongylus (Trichostrongyloidea: Heligmonellidae) in the large-headed rice rat Hylaeamys seuanezi, in the Atlantic Forest of northeast Brazil

“…According to Durette-Desset (1971a), the genus Hassalstrongylus is characterized by a non-hypertrophied genital cone, a symmetrical or subsymmetrical caudal bursa and a synlophe with a number of ridges ranging from 19 to León et al, 2000;Weirich et al, 2016). Because of the number of ridges (24 in the middle body) and the characteristics of the caudal bursa (subsymmetrical with non-hypertrophied genital cone), the specimens studied here can be included in the genus Hassalstrongylus.…”

Nematodes Associated With Mammals in the Great American Biotic Interchange (Gabi)

“…These results are concordant with the origin and subsequent diversification of cricetid rodents in South America. In addition, new records for species of Hassalstrongylus and Guerrerostrongylus appear to contribute to this hypothesis (Digiani et al 2015;Weirich et al 2016), in that the majority of the species are present in defined biomes of the South American continent and the parasites are frequently found in unrelated species of cricetid rodents.…”