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Puparia and third instar of a new diminutive whitefly, Regiominutus ventralis gen. et sp. nov. found infesting underside leaves of Aglaia elaeagnoides (A. Juss) (Meliaceae) on the Andaman Islands, India, are diagnosed, described and discussed. Regiominutus gen. nov. differs from allied genera, Aleuroclava Singh, Aericerus Dubey, Aleuroparvus Dubey, Aleuropleurocelus Drews and Sampson and Tetralicia Harrison in having a submarginal ventral groove, from the former two in having a deflexed submargin and smaller ventral surface and from the latter two in having a caudal furrow. Affinities and differences of the new genus shared with related genera are discussed. Puparium characters observed in slide mounts versus scanning electron microscope (SEM) images are presented. Line drawings, habitus images and SEM, microphotographs of the type specimens are given for the new taxa. This is the first whitefly species to be recorded from this host plant. [ABSTRACT FROM AUTHOR]

A new species of the genus Macrochlamys has been described from Western Himalaya, India. A total of 12 dry and seven live specimens of Macrochlamys leggeae sp. nov. were collected from the high-altitude region of Valley of Flowers National Park and are described here as a new species based on morph-taxonomy, conchological differences, and characters of the radula and genitalia. Collected specimens were compared with the closely related species Macrochlamys nuda (Pfeiffer, 1852), Macrochlamys vesicula (Benson, 1838), Macrochlamys glauca (Pfeiffer, 1846) and Macrochlamys kuluensis Blanford, 1904 and found to be significantly different in morphometric characters and in shell ratio. Additionally, high-resolution scanning electron microscope images of the radula with rechidian teeth measurements and a detailed description of the genitalia of M. leggeae are included. The new species is named after Joan Margaret Legge, Botanist of the Royal Botanical Gardens, Kew, who lost her life during floral study in the Valley of Flowers National Park in 1939. In addition to the description of the new species, a complete list of Macrochlamys species recorded from India is provided. [ABSTRACT FROM AUTHOR]

The genus Plesiophrictus is diagnosed and redescribed based on type material and additional specimens. The type species P. millardi (Pocock 1899) is redescribed. The genus Heterophrictus is revalidated, with H. milleti as type species. Heterophrictus differs from Plesiophrictus by the absence of serrula on maxillae and by having a rastellum on the chelicerae and stiff, spike-shaped setae on the prolateral coxae I. The significance of characters used in the taxonomy of both genera is discussed. [ABSTRACT FROM AUTHOR]

Cretaceous phosphorites from the onshore of Tamil Nadu have been investigated for their origin and compared with those in the offshore. Cretaceous phosphorites occur as light brown to yellowish brown or white nodules in Karai Shale of the Uttatur Group in the onshore Cauvery basin. Nodules exhibit phosphatic nucleus encrusted by a chalky shell of carbonate. The nucleus of the nodules consists of light and dark coloured laminae, phosphate peloids/coated grains and detrital particles interspersed between the laminae. Scanning electron microscope (SEM) studies reveal trapping and binding activity of microbial filaments. A mat structure with linearly arranged microbial filaments and hollow, cell-based coccoid cyanobacterial mat are present. Nodules contain abundant carbonate fluorapatite, followed by minor calcite, quartz and feldspar. The P2O5 content of the phosphorites ranges from 18 to 26%. The CaO/P2O5, Sr and F contents are higher than that of pure carbonate fluorapatite. Concentrations of Si, Al, K, Fe, and Ti are low. We suggest that the nuclei of the nodules represent phosphate clasts related to phosphate stromatolites formed at intertidal conditions. At high energy levels the microbial mats were disintegrated into phosphate clasts, coated with carbonate and then reworked into Karai Shale. On the other hand, Quaternary phosphorites occur as irregular to rounded, grey coloured phosphate clasts at water depths between 180 and 320m on the continental shelf of Tamil Nadu. They exhibit grain-supported texture. Despite Quaternary in age, they also resemble phosphate stromatolites of intertidal origin and reworked as phosphate clasts onto the shelf margin depressions. Benthic microbial mats probably supplied high phosphorus to the sediments. Availability of excess phosphorus seems to be a pre-requisite for the formation of phosphate stromatolites. [ABSTRACT FROM AUTHOR]

This paper reports the findings of experimental studies with regard to some common engineering properties (e.g., grain size, specific gravity, compaction characteristics, and unconfined compression strength) of both low and high calcium fly ashes, to evaluate their suitability as embankment materials and reclamation fills. In addition, morphology, chemistry, and mineralogy of fly ashes are studied using scanning electron microscope, electron dispersive x-ray analyzer, x-ray diffractometer, and infrared absorption spectroscopy. In high calcium fly ash, mineralogical and chemical differences are observed for particles, >75 μm and the particles of <45 μm size. The mode and duration of curing significantly affect the strength and stress–strain behavior of fly ashes. The geotechnical properties of fly ash are governed by factors like lime content (CaO), iron content (Fe2O3) and loss on ignition. The distinct difference between self-hardening and pozzolanic reactivity has been emphasized. [ABSTRACT FROM AUTHOR]