Rediscovery and new morphological data on two Hassalstrongylus (Nematoda: Heligmonellidae) coparasitic in the marsh rat Holochilus chacarius (Rodentia: Cricetidae) from Argentina

DIGIANI, M.C.; NOTARNICOLA, JULIANA; NAVONE G. T.

JOURNAL OF PARASITOLOGY

AMER SOC PARASITOLOGISTS

Lugar: Washington, Estados Unidos; Año: 2015 vol. 101 p. 556 - 564

0022-3395

Two species of Hassalstrongylus Durette-Desset, 1971coparasitic in Holochiluschacarius Thomas (Rodentia, Cricetidae),not recorded since their original description in 1937, were newly found in their type host and locality. Hassalstrongylusmazzai(Freitas, Lent and Almeida, 1937) and Hassalstrongylus argentinus (Freitas, Lent andAlmeida, 1937) were obtainedfrom Holochilus chacarius from two different populations: one from Salta Province (northwestArgentina) and another from Chaco Province (northeast Argentina). The speciesdescribed as Heligmonoides mazzai Freitas, Lent and Almeida, 1937 had been transferredto Hassalstrongylus even though its synlophe had never been studied. We provide the firstdescriptions and illustrations of the synlophe of males and females of H.mazzai and the female of H. argentinus, accounting for morphological and metrical variability. Weconfirm, through the study of the synlophe, the placement of H. mazzai in the genus Hassalstrongylus, and designate neotypes for the species sincethe type material deposited by the authors could not be found. Females of bothspecies were morphologically very similar and a Principal Components Analysisperformed on some morphometrical characters showed that the body length, uteruslength, and an unexpected character as the eggs number were useful charactersin the discrimination of both species.