Research Abstract
With diversity of hosts range, most identified nematode species still lack the crucial connection between
morphological and molecular make-up, which is important for precisely classifying the specimens. The
present study provides the complete description of Rhabdias africanus in the new host record,
Sclerophrys regularis. Fifty toad specimens were collected, and a high prevalence of R. africanus infection
(74%) was observed. Morphology and ultrastructure were observed using light and scanning electron
microscopes. Morphological characteristics, including peculiarities of the head, the shape and position
of the lips, and the number of labial papillae, were described. The length of the body, the esophageal
length, the distance from an anterior end to the nerve ring, and the tail length were reduced in the stud
ied samples relative to previously described specimens. Furthermore, some variable matrices that have
not previously been described, e.g., ovarian part widening, the nerve ring and its location, and eggs with
different stages of larvae, were included in the present study. Genus and species identification was con-
firmed by comparing partial 12S (619 bp) and ITS (878 bp) gene sequences to those of Rhabdias species
deposited in GenBank. The studied species showed a 99.34% resemblance to R. africanus from South
Africa. We assume our findings will aid in the molecular identification of adult and larval stages of this
genus in amphibians. We strongly recommend further studies on the environmental factors that promote
Rhabdias infection and transmission.
Research Date
Research Department
Research Member
Research Publisher
Saudi journal of biological science
Research Vol
29
Research Year
2022
Research Pages
103366