Quorum sensing (QS) plays an important role in virulence, biofilm formation and survival of many pathogenic bacteria including Pseudomonas aeruginosa. This signalling pathway is considered as novel and promising target for anti-infective agents. In the present investigation, effect of the Sub-MICs of clove oil on QS regulated virulence factors and biofilm formation was evaluated against P. aeruginosa PAO1 and Aeromonas hydrophila WAF-38 strain. Sub-inhibitory concentrations of the clove oil demonstrated statistically significant reduction of las- and rhl-regulated virulence factors such as LasB, total protease, chitinase and pyocyanin production, swimming motility and exopolysaccharide production. The biofilm forming capability of PAO1 and A. hydrophila WAF-38 was also reduced in a concentration-dependent manner at all tested sub-MIC values. Further, the PAO1-preinfected Caenorhabditis elegans displayed an enhanced survival when treated with 1.6 percent v/v of clove oil. The above findings highlight the promising anti-QS-dependent therapeutic function of clove oil against P. aeruginosa.

This article presents a detailed overview about one of the most important yet neglected fields of science, the Taxonomy, its relevance and the various impediments faced by it in recent times. Since the period 2011-2020 has been declared the Biodiversity decade, the Convention of Biodiversity has laid major emphasis on the inventory and conservation of biodiversity. However, it is a fact that the ignorance about our faunal and floral wealth can be detrimental for our own survival. With the decline in taxonomy and the disappearance of taxonomists worldwide, we are slowly heading towards a state of uncertainty and chaos as most of our studies require an accurate identification of test organism which is not a job that anyone or everyone can do. Therefore, this article highlights the stringent measures that are required to be taken by the taxonomists as well the various policy making agencies towards the revival and promotion of Taxonomy.

All metazoans are exposed to a wide range of microbes and have evolved complex immune defenses used to repel infectious agents. Coelomocytes play a key role in the defense reactions of most invertebrates. They are involved in important immune functions, such as phagocytosis, encapsulation, graft rejection, and inflammation, as well as the synthesis and secretion of several humoral factors especially in annelids and echinoderms. Coelomocytes in nematodes are variable in shapes from round, ovoid, cuboidal, and spindle-shaped to stellate or branched cells that are found usually at fixed positions in the pseudocoelom. Their number usually varies from 2 to 6. The model nematode,C. eleganslacks an adaptive immune system and the coelomocytes are capable of endocytosis, but their involvement in phagocytosis of bacteria seems unlikely. The aim of this review is to evaluate current knowledge on coelomocytes of invertebrates with special reference to nematodes. The morphology and structure of these coelomocytes are discussed along with their origin. Their relative positions and diversity in different nematode groups have also been discussed and illustrated.

This paper provides descriptions of two new and one known species of the genus Anaplectus De Coninck & Schuurmans Stekhoven, 1933. Anaplectus sudhausi sp. nov. is characterised by leaf-shaped lips interspersed with interlabial liplets; bifid apices of the lateral lips; cheilostom with non-cuticularised walls; gymnostom with cuticularised arcuate walls; 120–132 sublateral hypodermal glands on each body side with an additional 5–8 smaller subdorsal hypodermal glands; female tail with three caudal setae; males with arcuate spicules having manubrium slightly wider than calomus or blade, last median tubulus or supplement about half the spicule length and tail terminus with a weakly cuticularised spinneret. A. labiosulcus sp. nov. is characterised by 115–123 sublateral hypodermal glands on each side of the body with those on the dorsal side usually larger than the ventrals; the 5–6 anteriormost glands are unpaired and arranged linearly; lips with cuticularised interlabial grooves; gymnostom arched, occasionally double-arched and caudal glands grouped and opening through a cuticularised spinneret. A. granulosus (Bastian, 1865) De Coninck & Schuurmans Stekhoven, 1933 has been redescribed with some minor differences from previous descriptions.

A new species of Rhabditinae collected from compost, is described and illustrated together with observations on embryonic and post-embryonic development. Oscheius shamimi sp. n. is characterised by a medium-sized body (female: L = 0.76-1.52 mm, a = 12-20, b = 4.2-6.3, c = 6.8-13.8, c′ = 4.1-5.8, V = 45-51), finely annulated cuticle; slightly demarcated lip region; lips fused to form three doublets; six lines in lateral field; small stoma with isomorphic metastegostom; cylindrical pharyngeal corpus; slightly protruded vulval lips with subventral cuticular flap; long, proximally dilated, rectum; 53-61 μm long, robust spicules with long capitula having strongly cuticularised ventral walls; pseudopeloderan bursa with nine pairs of genital papillae in 1 + 1 + 1/3 + 3 + ph configuration and six to seven pairs of copulatory muscle bands. Oscheius shamimi sp. n. is amphimictic with a 1:1 sex ratio. The eggs are ovoid and smooth-shelled and measure 48-78 × 37-48 μm. Most eggs are laid in the late stages of embryonation. The embryonation time was 14-15 h at 25 ± 2°C. The genital primordium was orientated obliquely to the longitudinal axis and did not show division of primordial nuclei during the first moult. The didelphic female reproductive system was formed as a result of anterior and posterior elongation of the primordium while the monorchic reproductive system of the male developed from an anterior elongation of the primordium. The life cycle from egg to adult was completed in 3-3.5 days at 25 ± 2°C.

Two new diplogastrid species, Diplogastrellus sikorai sp. n. and Fictor composticola sp. n., are described and illustrated. Another species, D. gracilis, is reported for the first time from India and is redescribed with an emended diagnosis and SEM details. Diplogastrellus sikorai sp. n. is characterised by relatively small-sized body (female: L = 0.49-0.65 mm, a = 24-30, b = 4.9-6.3, c = 2.4-2.8), with a prominent, upright, dagger-like dorsal tooth and well developed subventral ridge; pore-like vulva, large post-uterine sac; ventrally arcuate spicules with rounded capitula and rosethorn-shaped gubernaculum with proximal spur and lateral sleeves around the spicules. Fictor composticola sp. n. is characterised by medium-sized body, eight cheilostomal plates with 18-22 cheilostomal filaments; gymnostom and stegostom with serrated anterior margins; dorsal and right subventral stegostomal walls each bearing a more or less equal tooth; left subventral stegostomal wall with two adjacent serrated plates; males with weakly cephalated, slender, ventrally arcuate spicules; wedge-shaped gubernaculum with tapering proximal end and lateral sleeves surrounding the distal ends of the spicules; and nine pairs of caudal papillae.

Detailed SEM observations were made on Tobrilus paludicola Micoletzky, 1925 and on its developmental biology. The cuticle is marked with fine transverse striations. The lip region is continuous and lips are broadly triangular in shape. The labial papillae are in a 6+6+4 arrangement. Amphids are small, ovoid, post-labial apertures. Embryonic development is completed 18-26 h after egg laying. The gonad in males and females develops from a single primordium. The supplement formation in third stage male juveniles is marked by the formation of numerous ventral chord supplement nuclei and finally their aggregation in groups at definite distances at a later stage.

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