Ascaridoid nematodes of amphibians and reptiles: Multicaecum and Brevimulticaecum

Abstract

The genus Multicaecum Baylis 1923, sensu Hartwich 1957, was found to be heterogeneous, comprising species which are relegated to two distinct genera, namely Multicaecum Baylis, 1923 and Brevimulticaecum. The latter name is derived from the subgenus Brevimulticaecum Mozgovoy, in Skrjabin, Shikhobalova, and Mozgovoy, 1951 by raising it to generic rank and emending the definition. Multicaecum contains a single species, agile Wedl, 1861 occurring in Crocodylus spp. in Africa, India and Australia, and is characterized by smooth rounded lips, each with a dentigerous ridge comprising small sharp denticles. The excretory pore is level with the nerve ring or behind it, and the ventricular appendices are long and slender. The species gangeticum Maplestone 1930 and quadrata Linstow 1904 are excluded from Multicaecum and regarded as species inquirendae incertae sedis. Brevimulticaecum contains five species occurring in the caimans and the alligator of the New World: baylisi Travassos, 1933 (type species; acuticauda Schuurmans-Stekhoven, 1937 is placed in synonomy under baylisi); stekhoyeni Baylis, 1947; tenuicolle Rudolphi, 1819; and two new species. Brevimulticaecum spp. are characterized by flat lips with alate margins and notches, without dentigerous ridges, excretory pore in front of or at nerve ring and the ventriculus with short appendices. The significance of this proposal is discussed in relation to the other genera of ascaridoid nematodes in crocodilians.

Helminth community dynamics in a population of Pseudopaludicola pocoto (Leptodactylidae: Leiuperinae) from Northeast-Brazilian

“…The genus is characterized by having smooth lips with winged margins and absence of dentigerous furrows, excretory pore located anterior to the nerve ring and ventricle with short appendages (González & Hamann, 2013). Immature individuals of Brevimulticaecum were recorded infecting species such as the Brazilian snake Bothrops neuwiedi Wagler in Spix, 1824, the treefrog Dendropsophus minutus Peters, 1872 and in the freshwater fishes Gymnotus carapo Linnaeus 1758 and Loricariichthys brunneus Hancok 1828 (Sprent, 1979; Moravec and Kaiser, 1994; Moravec et al, 1997 and Vieira et al, 2010) (Fig. 7h).…”

“…The nematodes were cleared in lactophenol or lactic acid while acanthocephalans were removed from their cysts, stained in carmine, and cleared in creosote. All endoparasites were observed and identified to the lowest possible level under a light microscope DMLB (Leica) and DM 5000B with interferential phase contrast, according to the literature (Yamaguti, 1961; Sprent, 1979; Vicente et al, 1991; Anderson, 2000 and Gibbons, 2010). All parasites were deposited at the Coleção Parasitológica do Laboratório de Zoologia from Universidade Regional do Cariri – LZ-URCA (Parasitological Collection of the Laboratory of Zoology).…”

Some ascaridoid nematodes of fishes: Heterocheilinae

“…Moreover, the lips in Multicaecum are short, rounded and possess dentigerous ridges; whereas in M. heterotis the lips are without dentigerous ridges. Khalil (1984 considered that this species fits the definition of Brevimulticaecum sensu Sprent (1979a). The lobular ventriculus and alate lips, with rounded margins lacking interlocking facets, precludes Dujarinascaris as defined by Sprent (1977).…”

“…There is no doubt that this species, by the structure of the lips, oesophageal ventriculus and by the features of the spicules, gubernaculum and male tail, is a heterocheiline. A characteristic feature of this species is the lobular form of the ventriculus, whereas in the genus Multicaecum the ventriculus possesses five relatively long appendices (Sprent, 1979a). A characteristic feature of this species is the lobular form of the ventriculus, whereas in the genus Multicaecum the ventriculus possesses five relatively long appendices (Sprent, 1979a).…”

“…According to the revision of Brevimulticaecum Mosgovoy, in Skrjabin et al, 1952by Sprent (1979a, this species most closely resembles Brevimulticaecum pintoi Sprent, 1979, but the spicules are more than twice as long relative to the body length and the ejaculatory duct. The spicules are also longer relative to body length and ejaculatory duct than in B. tenuicolle (Rudolphi, 1819), but are not as long as in B. baylisi (Travassos, 1933).…”