New species in the genus Monoecocestus (Cestoda: Anoplocephalidae) from neotropical rodents (Caviidae and Sigmodontinae)

Monoecocestus (Cestoda: Anoplocephalidae) diversity in Sigmodontinae rodents characterized by morphology and molecular methods

This paper provides new morphological and molecular data for identifying Monoecocestus species from rodents: a) morphological update of Monoecocestus spp., b) morphological data on Anoplocephalidae taxa from Sigmodontinae rodents, c) analyses of the genetic distances between the specimens studied and other Anoplocephalidae from rodents available in GenBank, and phylogenetic inferences. A total of 25 specimens of Holochilus spp. were examined from four provinces of Argentina. Cestodes specimens were removed from the rodents small intestines. Conventional studies were used for the morphological and molecular analysis. Four taxa of Monoecocestus were identified. Monoecocestus threlkeldi was identified as first record in Holochilus chacarius and from Argentina. Molecular and morphological aspects of Monoecocestus sp.1, Monoecocestus sp.2 and Monoecocestus sp.3 were described. Specimens belonging to the genus Monoecocestus may represent closely related species, demonstrating the importance of using integrative taxonomic approaches to understand biological diversity. The continuity of the studies on Anoplocephalidae will allows to advance in investigation of molecular analyses and ecological aspects that determine parasite-host-environment relationship.

Systematic position of the enigmatic Quentinia mesovitellinica (Rêgo, 1967) (Cestoda, Cyclophyllidea)

The systematic position of Quentinia mesovitellinica (Rêgo, 1967) (Cestoda, Cyclophyllidea) from the hystricomorph rodent Galea spixii (Wagler) (Caviidae) in Brazil is reevaluated based on published information. Quentinia mesovitellinica is generally thought to belong to the family Catenotaeniidae, being thus the only catenotaeniid cestode parasitizing hystricomorph rodents and also the only catenotaeniid in South America. However, the present study shows that Q. mesovitellinica differs fundamentally from Catenotaenia Janicki, 1904 sensu lato and other catenotaeniids with respect to several morphologic features, but shares these features with Monoecocestus Beddard, 1914 sensu Beveridge (1994), a genus in the family Anoplocephalidae sensu stricto (i.e. sensu Spasskii, 1951). However, Q. mesovitellinica is not assigned here to Monoecocestus, because the latter is a morphologically heterogeneous genus and will probably be split when subjected to a comprehensive phylogenetic and taxonomic analysis. Instead, Quentinia Spasskii, 1969 is considered a valid genus in the family Anoplocephalidae s. s. The morphologically closely related Monoecocestus eljefe Haverkost & Gardner, 2010 from Galea musteloides Meyen in Bolivia is assigned to Quentinia as Q. eljefe (Haverkost & Gardner, 2010) n. comb. An amended diagnosis is provided for Quentinia.

Hymenolepidid cestodes: Diversity, morphological and molecular characterization of a new species, and phylogeny of parasitic species of rodents from North and South America

Rodents are hosts of a wide diversity of cestodes. Fifteen genera included in the family Hymenolepididae parasitize rodents, and only four of these genera have been recorded from the Neotropical region. The purpose of this paper is to update species of Hymenolepididae from rodents, describe a new species of Hymenolepis based on morphological and molecular characterization (ITS1 rDNA and cox1 mtDNA), comparing the features among the species from North and South American rodents, and provide phylogenetic inferences of Hymenolepididae from rodents based on sequences available in the GenBank. Rodents were collected in the Parque Provincial Ernesto Tornquist, Buenos Aires, Argentina. Hymenolepis ivanovae n. sp. differs from other Hymenolepis species registered from North and South American rodents by body size, scolex, suckers, cirrus sac, cirrus, testes, and eggs, among others. Comparative morphometric data for Hymenolepis species from North and South American rodents is provided. Molecular analyses place H. ivanovae n. sp. within the genus Hymenolepis with strong support, and show it close to species of zoonotic importance. The new species is the first species of Hymenolepis described from Sigmodontinae rodents.

New record of anoplocephalid eggs (Cestoda: Anoplocephalidae) collected from rodent coprolites from archaeological and paleontological sites of Patagonia, Argentina

Results of paleoparasitological examination of rodent coprolites collected from archaeological and paleontological sites from Patagonia, Argentina, are present. Each coprolite was processed, rehydrated, homogenized, spontaneously sedimented and examined using light microscope. Coprolites and eggs were described, measured and photographed, and were compared with current faeces of Lagidium viscacia. Eggs with morphological features, attributed to an anoplocephalid cestode were found in samples collected from Cueva Huenul 1 (36°56'45″S, 69°47'32″W, Neuquén Province, Holocene) and Los Altares Profile (43º53'35″S, 68º23'21″W, Chubut Province, Late Holocene). These are the first findings of this anoplocephalid from faecal material from patagonic rodents.