Genetic evidence for three species within Pseudoterranova decipiens (nematoda, ascaridida, ascaridoidea) in the north atlantic and norwegian and barents seas

Fitness of the marine parasitic nematode Anisakis simplex s.str. in temperate waters of the NE Atlantic

“…As a consequence of different selection pressures, the identification of morphological, biochemical and genetic markers has revealed substantial intraspecific variation within anisakids among different microenvironment types. This has been well documented in Contracaecum osculatum s. l. (Fagerholm 1989, Nascetti et al 1993, Orecchia et al 1994), Anisakis simplex s. l. (Threlfall 1982, Smith 1983b, Mattiucci et al 1997, Siles et al 1997, Pascual et al 1999, and Pseudoterranova decipiens s. l. (Paggi et al 1991, Bristow & Berland 1992, George-Nascimento & Llanos 1995. Morphometric and growth variations among wild larvae collected from the 3 host sampled species agreed with the electrophoretic variations of ES2 products of larvae grown in vitro, which are known to be produced during invasion of the host's tissues (Raybourne et al 1986).…”

Specificity and host suitability ofCucullanus genypteri(Nematoda: Cucullanidae) in threeGenypterus(Ophiididae) fish host species from the southeastern Pacific Ocean

“…In the Pacific Ocean, the only phenotypic traits allowing to suspect the existence of more than one Cucullanus species are the longer oesophagus of para sites in golden lings, and the longer spicules of males collected from the red ling than in males collected from the two other hosts species (Table I). It would not be surprising, however, that electrophoretic analysis reveal that this is a species complex, as reported for several marine ascaroid nematodes and other helminth para sites (e.g., Bullini et al, 1978;Nascetti et al, 1986;Orecchia et al, 1986;Paggi et a., 1991 ;Nascetti et al, 1993 ) is the covariable and the host species is the factor, d.f. = degrees of freedom, SS = sum squares.…”

Phylogeny of the Ascaridoidea (Nematoda: Ascaridida) Based on Three Genes and Morphology: Hypotheses of Structural and Sequence Evolution

“…For example, members of this superfamily have been used for studies of respiratory biochemistry (Saz and Weil, 1960;Komuniecki et al, 1993), molecular genetics (Neuhaus et al, 1987;Kageyama, 1998), immunology (Jones et al, 1994), reproductive biology (Von Beneden, 1883;Foor, 1970), comparative morphology (Fagerholm, 1989(Fagerholm, , 1991Hugot et al, 1991), development (Boveri, 1899;Pilitt et al, 1981), life cycles (Huizinga, 1967;Klöser et al, 1992;Køie and Fagerholm, 1995), population genetics Nascetti et al, 1993;Nadler, 1996), and pathology (Beaver, 1956;Overstreet and Meyer, 1981;Kazacos, 1986). In contrast, much less is known about the evolutionary history of taxa in this superfamily, although certain organisms, e.g., Ascaris, Anisakis, have been studied in detail at the microevolutionary level (Paggi et al, 1991;Anderson et al, , 1995Anderson and Jaenike, 1997).…”