Molecular data reveal a new species of Rhopalias Stiles & Hassall, 1898 (Digenea, Echinostomatidae) in the Common opossum, Didelphis marsupialis L. (Mammalia, Didelphidae) in the Yucatán Peninsula, Mexico

Abstract

A new species of Rhopalias Stiles & Hassall, 1898 is described from the small intestine of the Common opossum, Didelphismarsupialis Linnaeus from the Yucatán Peninsula, Mexico. Rhopaliasoochisp. nov. is morphologically very similar to the type species of the genus, Rhopaliascoronatus (Rudolphi, 1819) Stiles & Hassall 1898, a species widely distributed in opossums across Mexico. A molecular phylogenetic analysis using a mitochondrial gene (cox1), and the nuclear ribosomal internal transcribed spacer region (ITS1-5.8S-ITS2), of specimens of R.coronatus collected in several localities of Mexico revealed that those from the Yucatán Peninsula, originally recorded on morphological grounds as R.coronatus actually represented an independent genetic lineage. Maximum Likelihood and Bayesian Inference analyses were performed for each data set independently, and for the concatenated data set (ITS1-5.8S-ITS2 + cox1). All phylogenetic analyses showed that the specimens from Yucatán represented a monophyletic lineage, with high bootstrap support and Bayesian posterior probabilities. In addition, the genetic divergence estimated between R.oochisp. nov. and two species of Rhopalias, R.coronatus, and R.macracanthus Chandler, 1932 that also occur in Mexican marsupials ranged between 7–8% and 16–17%, for cox1, and between 0.1–0.2% and 7% for the ITS region, respectively. The molecular evidence gathered in this study (reciprocal monophyly in both phylogenetic analyses, and estimated genetic divergence) suggested that the specimens found in the intestine of D.marsupialis originally reported as R.coronatus from Yucatán, actually represent a new species. Morphological evidence was found through light and scanning electron microscopy to support the species distinction based on molecular data.

Elucidating the life cycle of opossum parasites: DNA sequences reveal the involvement of planorbid snails as intermediate hosts of Rhopalias spp. (Trematoda: Echinostomatidae) in Brazil

“…The concentration of the extracted DNA was determined using a NanoDrop Lite spectrophotometer (Thermo Fisher Scientific, Wilmington, USA). Attempts were made to amplify partial fragments of 28S (primers digl2/1500R; [23]) and internal transcribed spacer region (primers BD1/BD2; [24]) regions of the nuclear ribosomal operon, and of mitochondrial genes nad1 (NDJ11 and NDJ2a; [25] or JB11 and JB12; [26]) and cox1 (Dice-1 and Dice-11 [27]; Dice-1 and BarCox-R [5]). DNA amplifications were performed by polymerase chain reaction (PCR) following the PCR conditions described by the authors listed above.…”

“…Echinostomatid digeneans belonging to the genus Rhopalias Stiles and Hassall, 1898 are intestinal flukes found mainly in didelphid opossums (occasionally reported in bats, rodents, and birds) in the Americas [1][2][3][4]. Species of the genus Rhopalias are unique among the echinostomatoideans due to the presence of two eversible proboscises armed with spines situated symmetrically on either side of the oral sucker [1,[3][4][5]. In the past, Rhopalias was included in the family Rhopaliidae Looss, 1899, as the type and only genus.…”

“…Currently, seven species of Rhopalias are considered valid [4,5]. The type-species of the genus, Rhopalias coronatus (Rudolphi, 1819), was originally described from marsupials in Brazil [3,7,8].…”

“…were available. Recently, sequence data for adult stages of three species of Rhopalias in North America have been made available [5,6,18], enabling molecular matching with other life cycle stages.…”

Identificación de helmintos en <i>Didelphis marsupialis</i> (Didelphidae) y <i>Rattus rattus</i> (Muridae) en el área metropolitana de Bucaramanga, Colombia

“…Escala: 500 µm. Presenta dos tentáculos anteriores armados con espinas(López- Caballero et al, 2019); F. Nippostrongylus sp., extremo anterior. Escala: 100 µm.…”