Further description of Aspidodera raillieti (Nematoda: Aspidoderidae) from Didelphis marsupialis (Mammalia: Didelphidae) by light and scanning electron microscopy

Abstract

Nematodes of the family Aspidoderidae (Nematoda: Heterakoidea) Freitas 1956 are widely distributed from Americas. The species of the genus Aspidodera Railliet and Henry 1912 are parasites of mammals of the orders Edentata, Marsupialia, and Rodentia. In the present work, Aspidodera raillieti (L. Travassos, Mem Inst Oswaldo Cruz 5(3):271-318, 1913), collected from the large intestine of Didelphis marsupialis (Mammalia: Didelphidae) from Valle del Cauca, Colombia, is redescribed. The association of light and scanning electron microscopy (SEM) allowed a detailed analysis of the morphology and ultrastructure of this nematode. Some taxonomic features, such as cephalic region, topography of the cuticle, sucker, spicules, posterior end of males, localization of vulva, the anus, and posterior end of females were observed. Important structures such as amphid, details of cephalic region, phasmid, and number and localization of caudal papillae are documented by SEM, for the first time adding characters to identify this species. Colombia is a new geographical record for A. raillieti.

MORPHOLOGICAL AND GENETIC CHARACTERIZATION OF NEMATODES OF THE OPOSSUM Didelphis albiventris AND THE ARMADILLO Dasypus novemcinctus FROM SERRA DA CAPIVARA NATIONAL PARK

“…Aspidodera vazi has smaller cephalic cap/body length ratio, 1:13 to 1:27, than other aspidoderids. The measurements and morphological characteristics of the species of the present study are in accordance with the data from Vicente et al (1966Vicente et al ( , 1997, Santos et al (1990), Chagas-Moutinho et al (2007 and Hoppe & Nascimento (2007). The eggs of the aspidoderids studied here are very similar in size and shape (elliptic, thin-shelled), but the new genetic sequences now available will certify their future diagnosis in coprolites.…”

“…The present study constitutes a new geographic locality of four species of Aspidoderidae, a Trichostrongylidae species, and presents new Species of Aspidodera parasitize a wide range of mammal hosts in Brazil (see Figure 9), which shows the known distribution of these parasites, especially in members of Didelphidae and Dasypodidae. The species of Aspidodera can be differentiated by the morphology of cephalic cap and cordons, which contain six longitudinal loops, shape and size of esophagus with a terminal bulb, ventral sucker on males, spicules and gubernaculum, and digitiform projection on the posterior end (Santos et al 1990, Chagas-Moutinho et al 2007, Chagas-Moutinho et al 2014. The morphological identification of A. raillieti is well established and the species can be characterized by the anterior region bearing a cuticular expansion or cap that surpasses the length of the vestibule, adorned with cephalic cordons bearing six longitudinal loops that touch the base of the cephalic cap (Santos et al 1990).…”

Morphological Redescription of Dirofilaria immitis

“…However, scanning electron microscopy (SEM) has become an important tool that can add new taxonomic characters to previous species descriptions made by light microscopy (Chagas-Moutinho et al, 2007;Torres et al, 2007), as well as contributing to descriptions of new species Giese et al, 2009). Few reports have described D. immitis using this technique, although Wong and Brummer (1978) conducted a comparative study of filarial longitudinal ridges, and included D. immitis, while Rodrigues-Silva et al (1999) described the rugosae area and the posterior end of male D. immitis.…”

First Report of Oligacanthorhynchus microcephalus (Rudolphi, 1819) (Acanthocephala: Oligacanthorhynchidae) in Didelphis albiventris (Lund, 1841) (Marsupialia: Didelphidae) in Southeastern Brazil

“…In summary and according to taxonomic keys and descriptions by different authors, [23][24][25][26] the morphological characteristics of the nematodes were consistent with Aspidodera raillieti (Travassos, 1913) (Nematoda: Aspidoderidae), a typical parasite of opossums in Brazil and other parts of the Americas. 6,7,18,20,24,[26][27][28][29][30][31][32][33][34][35][36][37][38] The of specimen acanthocephalus had a white, pleated, fusiform, spiral-shaped body with marked transverse wrinkles, and a proboscis broadly armed with six longitudinally arranged spiral rows, each with six shallowly rooted hooks, making a total of 36 hooks, and a well-developed muscular copulatory bursa, roughly orbicular, at the posterior end, all characteristics compatible with a male specimen of O. Microcephalus. 3,15…”