The morphological and molecular characterization of Baylisascaris devosi Sprent, 1952 (Ascaridoidea, Nematoda), collected from Pine marten (Martes martes) in Iran

Abstract

Background Baylisascaris devosi is an intestinal nematode found in several carnivores including fisher, wolverine, Beech marten, American marten and sable in different parts of the world, but this nematode has not been reported from Pine marten. Therefore, this study aimed to identify Baylisascaris isolated from a Pine marten in Iran using morphological and molecular approaches. Methods Specimens of B. devosi were collected from one road-killed Pine marten in northern Iran. Morphological features were evaluated using scanning electron microscopy, energy dispersive x-ray analysis and ion sectioning. The molecular characterization was carried out using partial Cox1, LSU rDNA and ITS-rDNA genes. Results The nematodes isolated from the Pine marten were confirmed to be B. devosi based on the morphological features and the sequence of ribosomal and mitochondrial loci. X-ray scans (EDAX) were completed on gallium cut structures (papillae, eggs, male spike and mouth denticles) of B. devosi using a dual-beam scanning electron microscope. The male spike and mouth denticles had a high level of hardening elements (Ca, P, S), helping to explain the chemical nature and morphology of the worm. Based on these genetic marker analyses, our sequence had the greatest similarity with Russian B. devosi isolated from sable. Conclusions In this study, to our knowledge, the occurrence of B. devosi infection in Pine marten is reported for the first time. Molecular analysis showed that these three genes are suitable molecular markers for identification and inferring phylogenetic relationships of Baylisascaris species. Furthermore, the high divergence of Cox1 between Baylisascaris species indicates that Cox1 could be used for their phylogenetic and taxonomic studies.

Morphology and ASAP analysis of the important zoonotic nematode parasite Baylisascaris procyonis (Stefahski and Zarnowski, 1951), with molecular phylogenetic relationships of Baylisascaris species (Nematoda: Ascaridida)

“…Among the 9 species of Baylisascaris, B. tasmaniensis showed sister relationship to the remaining Baylisascaris in the phylogenetic trees based on the ITS data, which are accordant with the previous phylogenetic studies (Sharifdini et al, 2021; Barrera et al,…”

“…Among the 9 species of Baylisascaris , B. tasmaniensis showed sister relationship to the remaining Baylisascaris in the phylogenetic trees based on the ITS data, which are accordant with the previous phylogenetic studies (Sharifdini et al , 2021; Barrera et al , 2022), but are in conflict with other phylogeny (Camp et al , 2018). The phylogenetic relationships of B. tasmaniensis and the others Baylisascaris spp.…”

“…The morphology of B. procyonis is very similar to B. columnaris , and some previous phylogenetic studies also supported B. procyonis and B. columnaris have a close affinity (Franssen et al , 2013; Tokiwa et al , 2014; Mata et al , 2016; Camp et al , 2018; Sharifdini et al , 2021). Overstreet (1970) considered the morphology of lips and first pair of postcloacal papillae to be important characters for distinguishing B. procyonis from B. columnaris (lips possessing remarkable medio-apical notch and the first pair of postcloacal papillae being double in B. procyonis vs the medio-apical notch of lips unconspicuous and the first pair of postcloacal papillae not being double in B. columnaris ).…”

“…Consequently, the genus Baylisascaris currently includes 10 recognized species. Although the phylogenetic analyses of Baylisascaris species were investigated using different genetic data in some previous studies (Nadler, 1992; Nadler and Hudspeth, 1998, 2000; Xie et al , 2011 a , 2011 b ; Tokiwa et al , 2014; Mata et al , 2016; Camp et al , 2018; Li et al , 2018; Sharifdini et al , 2021), the phylogenetic relationships of these 10 Baylisascaris species remain unclear, because all of the previous phylogenetic studies only included a limited number of species.…”

Molecular identification of a new species of Rhigonema (Nematoda: Rhigonematidae) and phylogenetic relationships within the infraorder Rhigonematomorpha

“…In Rhigonematomorpha, only 21 nominal species have been genetically characterized [14-17, 19, 20], and most of the data available are represented by the 18S and 28S sequences, which are commonly used for molecular phylogeny of higher taxa within Nematoda [21][22][23][24][25][26]. Although the nuclear internal transcribed spacer (ITS) region and the mitochondrial cox1 and cox2 genes are widely used as powerful and practical genetic markers for revealing sibling or cryptic species, delimiting phenotypic variation and identifying species in the infraorders Ascaridomorpha, Spiruromorpha and Oxyuridomorpha [27][28][29][30][31][32][33][34][35][36][37][38][39][40][41][42][43][44], they have been scarcely employed in studies pertaining to Rhigonematomorpha species. Consequently, no current knowledge on the effectiveness of ITS, cox1 and cox2 as genetic markers for identification of Rhigonematomorpha nematodes is available.…”