Egg shell ultrastructure of the fish nematode Huffmanela huffmani (Trichosomoididae)

Abstract

Abstract. The egg shell of Huffmanela huffmani Moravec, 1987 forms three main layers: an outer vitelline layer, a middle chitinous layer, and an inner lipid layer. The vitelline layer, forming the superficial projections of the egg shell, comprises two parts: an outer electron-dense, and an inner electron-lucid part. The chitinous layer is differentiated into three parts: an outer homogenous electron-dense part, a lamellated part, and an inner electron-dense net-like part. The lipid layer comprises an outer net-like electron-lucid part, and an inner homogenous electron-lucid part. The polar plugs are formed by electron-lucid material with fine electron-dense fibrils.

Huffmanela sp. (Nematoda: Trichosomoididae: Huffmanelinae) encountered in the whitecheek shark (Carcharhinus dussumieri) in the Arabian Gulf

“…Previously, only a single study had reported the ultrastructure of eggshells of Huffmanela sp., namely H. huffmani , using TEM ( Zdarska et al ., 2001 ), which showed finer morphological differences than those reported here. While both studies agree that the chitinous layers of the eggs consist of two parts that differ in electron density, the chitinous layers of H. huffmani were found to be lamellated in the inner part, while here the chitinous layers were found to be homogenous and non-lamellated.…”

“…Specimens were prepared according to the previously described procedures of Zdarska et al . (2001) .…”

Effect of a formulation of Bacillus firmus on root-knot nematode Meloidogyne incognita infestation and the growth of tomato plants in the greenhouse and nursery

“…Saxena et al (2000) reported that production of different types of antibiotics and enzymes is nature of Bacillus species, which are strongly antagonistic to several pathogens such as root-knot nematode. Nematode egg shells consists of three layers namely, vitelline, chitinous and lipid layers (Zdarska et al, 2001). It might be possible that B. firmus secretes some toxins, which damages the egg shell of root-knot nematode.…”

Nematode eggshells: A new anatomical and terminological framework, with a critical review of relevant literature and suggested guidelines for the interpretation and reporting of eggshell imagery

“…This error, unfortunately, was repeated in subsequent reports for other species of the genus [64,77,91,121]. The egg specimens studied by Žďárská et al (2001) [125] had extremely electron-dense Chitinous Layers (nearly black in their TEMs) and the authors overlooked a uniformly thin, uniformly electron dense, membranelike layer closely appressed to the external surface of the Chitinous Layer in their fig. 4.…”

“…3rd Confusing Use: The ambiguity gets more complex with the third historical application of "vitelline layer." In the first published TEM study of a Huffmanela eggshell, Žďárská et al (2001) [125] used "vitelline membrane" to refer to the outermost layer of the H. huffmani egg, which we now know is a Uterine Layer (Section 4.2), and which is deposited by the uterus onto the outer surface of Layer #1! This error, unfortunately, was repeated in subsequent reports for other species of the genus [64,77,91,121].…”