Ultrastructure of Procamallanus (Spirocamallanus) halitrophus (Nematoda: Camallanidae) parasite of flounder

Abstract

The ultrastructure of the camallanid nematode Procamallanus (Spirocamallanus) halitrophus, a parasite of flounder, is described for the first time by the use of transmission electron microscopy. The body wall is composed of an outer cuticle, a hypodermis, and a muscular layer. The cuticle comprises the epicuticle, the cortical, median, fibrous, and basal layers. The cortical layer is subdivided into an outer zone and an inner zone; the median layer is subdivided into an outer layer, rich in electrondense fibrils, and an inner layer, which does not contain these fibrils; the fibrous layer is subdivided into three regions delimited by electrondense lines; the basal layer presents electrondense sustaining structures. Underlying the basal layer is the hypodermis where many organelles are observed. The musculature is striated, and each muscle cell consists of individualized contractile and non-contractile regions. Inclusion bodies are present in the muscle fibers, hypodermis, hypodermal chord, and in the intestine.

Ultrastructural Characteristics of the Body Wall in Adult Helminth Heterakis gallinarum Schrank, 1788 (Nematoda: Heterakidae)

“…There is information in the literature that the tubular structures noted in the basal part of the cuticle of H. gallinarum nematode (Fig. 2C) are also found in nematodes belonging to other families [54,55]. Those tubular structures were also noted in the nematode H. dispar, another representative of the family of the same name [15].…”

“…They are protein assemblies of different sizes formed as a result of expression of recombinant proteins. Cytoplasmic bodies are also found in other nematodes [55]. They were not observed in the hypodermis of H. gallinarum nematode.…”

“…There are some literature data on the ultrastructural structure of nerve columns located in the dorsal and ventral hypodermal ridges of nematodes. The ultrastructural characteristics of the neural columns of the nematodes Cystidicoloides ephemeridarum belonging to the family Cystidicolidae, Procamallanus halitrophus belonging to the family Camallanidae, Trichostrongylus colubriformis belonging to the family Trichostrongylidae and Haemonchus placei are given [55,59,61]. About the ultrastructure of the species belonging to the genus Heterakis, there are literature data on the study of H. spumosa and H. dispar species [14].…”

“…The conducted studies showed that the muscular system of H. gallinarum nematode is composed of somatic cells. According to the data of some researchers, there is a basal lamina between the hypodermis and the muscular layer [55]. Other authors report that there is a basement membrane at the boundary between the hypodermis layer and muscle cells [13,62].…”

Cytochemical Analysis of the Body Wall of the Flounder Parasite Procamallanus (Spirocamallanus) halitrophus (Nematoda: Camallanidae)

“…Very few studies exist describing the surface of fish nematodes by electron microscopy (Ca ´rdenas et al, 2005;Frantova ´et al, 2005). The present work represents the first cytochemical characterization of fish nematodes.…”