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1.
Zi-Wei Yin  Li-Zhen Li 《ZooKeys》2013,(346):23-27
Tangius indicus sp. n. (Batrisitae: Batrisini) is described and illustrated from the Indian States of Meghalaya (Khasi Hills, type locality) and West Bengal (Darjeeling). Specimens of the new species are similar to those of the recently described T. glabellus Yin & Li from Tibet, Southwest China, and can be separated only by minor differences of the male features.  相似文献   

2.
The length–weight relationships (LWRs) of four fish species were determined from Vembanad-Kole Wetland, Kerala, India between June 2015 and May 2016. Fish samples were collected monthly from various fishing gears such as gill nets (50 m long and 1.5 m height, mesh sizes 30–100 mm, soaking time 8 hr) and seine nets (mesh sizes 8–16 mm). Values of the parameter b ranged from 2.896 to 3.165 and such values are within the expected range. This study reports the new maximum total length for Channa pseudomarulius and Hyporhamphus xanthopterus.  相似文献   

3.
Twenty seven species of dinocysts belonging to seventeen genera are described and illustrated from the Middle Member of the Jhuran Formation in Kachchh, Western India. Among them, two new genera, nine new species and one new variety are introduced. The genera are Indodinium and Indosphaera and the new species are Escharisphaeridia psilata, Indodinium khariensís, Indosphaera bhujensis, Mendicodinium granulatum, M. microreticulatum, Nannoceratopsis radiatus, Parvocavatus scabratus, Sentusidinium hexagonalis and Scriniocassis downiei. The new variety is Gonyaulacysta jurassica subsp. jurassica var. quadrata. The dinocyst type A is also a new dinocyst, but at present no formal name is given to it, because only one specimen has been observed. Geiselodinium inaffectum is emended to include significantly larger size specimens.  相似文献   

4.
A five-year (1994–1999) continuous survey of aeromycoflora had been carried out in an agricultural farm at a suburban area of Greater Calcutta. The sampling was carried out with Burkard volumetric spore trap placed 0.5?meter above the ground level at the centre in a small plot in a rice field. A total of 26 fungal spore types were identified microscopically. The most abundant types were Basidiospores (21.85–5.59%) followed by Cladosporium, Periconia, Nigrospora, Aspergilli group, Ascospores. The seasonal periodicity of the major dominant types had maxima in autumn, during the month of October. This coincided with the harvesting period of the rice crop during rainy season. In Petri plate exposure of nutrient media, different species of aspergilli group, Alternaria, Cladosporium, Curvularia, Nigrospora, and other taxa were identified. The diurnal periodicities recorded for different types were classified into night-time, post dawn, middle day and double maxima (showing two peaks in a day) patterns. In general, no significant correlation between the total air spora and the meteorological parameters could be established. It is evident that the local cropping practices may have some regulating role on spore concentration in the air of the study area.  相似文献   

5.
Dehairs  F.  Rao  R. G.  Chandra Mohan  P.  Raman  A.V.  Marguillier  S.  Hellings  L. 《Hydrobiologia》2000,431(2-3):225-241
Stable carbon isotopic composition and C/N ratio were used to trace the input of carbon associated with mangrove litter into the estuary of the Godavari–Gautami delta system and Kakinada bay (Andhra Pradesh, India). Suspended organic matter in the mangrove channels was more depleted in 13C (average 13C = –24.5) than in Kakinada bay which showed 13C values for suspended matter (average 13C = –22.7) closer to those expected for marine phytoplankton. Suspended organic matter from mangrove channels was enriched in nitrogen (average C/N atom ratio 12.7) and 13C (average 13C = –24.5) relative to mangrove leaf litter, which had a C/N ratio of 75 and a 13C value of –28. Lowest C/N ratios for suspended matter were observed during southwest monsoon when rainfall was highest. Although in general, mangrove litter fall was also lower during this period, no clear correlation was observed between litter fall and C/N ratio of suspended matter. In general, the composition of suspended matter pointed towards phytoplankton as a major component. Isotopic composition of zooplankton suggested selective feeding on 13C-enriched, marine phytoplankton in open Kakinada bay and on 13C-depleted organic matter, such as estuarine phytoplankton and mangrove litter, in the mangrove channels. From the 13C signature, it appeared that mangrove carbon was present to some extent in zooplankton and macrofauna from the mangrove mudflats and channels, but the signal rapidly decreased in Kakinada bay. Nitrogen isotopic composition of zooplankton and macrofauna indicated a progressive enrichment of 15N away from the mangrove forest towards the northern part of Kakinada bay, in approach of Kakinada city. This is thought to reflect input of anthropogenic nitrogen enriched in 15N and subsequent uptake of this enriched nitrogen into the aquatic food chain.  相似文献   

6.
Summary Social or semisocial behavior in nomiine bees is here reported for the first time. InNomia capitata and perhaps inN. oxybeloides, presumed sister bees share cell clusters and cooperatively provision the same cells. Unlike other primitively social bees, the sisters simultaneously forage and oviposit. There is no apparent inhibition of the oviposition of daughters, although their nest-founding mother or perhaps an older sister appears to stay in the nest and continue to oviposit.Nesting behavior and nest structure ofNomia capitata andN. oxybeloides are similar; cells are vertical and clustered. In contrastNomia nasicana makes horizontal cells scattered along the main burrow.
Zusammenfassung Zum ersten Mal wird über soziales oder halbsoziales Verhalten von Bienen aus der Unterfamilie der Nomiinen berichtet. BeiNomia capitata und vielleicht auch beiN. oxybeloides teilen sich mehrere Bienen—wahrscheinlich Schwestern—ein und denselben Zellkomplex und verproviantieren auch die Zellen gemeinsam. Ganz im Gegensatz zu anderen sozial primitiven Bienen verproviantieren diese Nestgenossen nicht nur, sondern legen auch Eier. Die Fähigkeit Eier zu produzieren ist in diesen Bienen offenbar nicht unterdrückt, obwohl sich in jedem Nest ein eierlegendes Individuum befindet, die entweder die Nestgründerin, oder eine ältere Schwester sein muss. Im Nistverhalten und in der Struktur der Nester sind sichN. capitata undN. oxybeloides sehr ähnlich. Die Zellen stehen vertikal und sind in Gruppen angeordnet. Im Gegensatz dazu fertigtN. nasicana horizontal liegende Zellen, die entlang eines Tunnels verteilt sind.

Résumé Un comportement social est décrit pour la première fois chez des abeilles nomiine. ChezNomia capitata et probablementN. oxybeloides, il existe des abeilles surs qui partagent les cellules et les approvisionnent ensemble. Contrairement à d'autres abeilles à comportement social primitif, les surs butinent et pondent des ufs simultanément. Les filles ne montrent pas d'inhibition apparente de ponte malgré que leur mère ayant bâtit le nid, ou peut-être une vieille sur, reste dans le nid et continue à pondre des ufs.Le comportement et la structure des nids desNomia capitata, N. oxybeloides etNomia nasicana sont décrits.


Contribution No 1304 from the Department of Entomology, The University of Kansas, Lawrence. This paper is the second of a series on behavior of Halictidae in India; the others areBatra andMichener (1966) andBatra (1966).  相似文献   

7.
The present work is focused on the hipparionine remains from the late Miocene to early Pliocene deposits of the Haritalyangar areas, Himachal Pardesh, India. These remains are taxonomically ranked to five genera (Plesiohipparion, Proboscidipparion, Cormohipparion, Sivalhippus, and Eurygnathohippus) and seven species. The described taxa are predominantly known from China, Africa and the Indian subcontinent. Among these, Proboscidipparion is reported for the first time from the Siwaliks; the material assigned to Plesiohipparion sp. is a potential candidate for a new species. Hipparionines from this area have long been poorly known and are helpful to understand the palaeontological context of the Indian Siwalik mammalian fauna. The hipparionines suggest a wide variety of environmental conditions ranging from grasslands to forests.  相似文献   

8.
We studied the enhanced production of high quality biomass, δ-aminolevulinic acid (δ-ALA), bilipigments, and antioxidants from five tropical blue green algae (cyanobacteria) in a full factorial design using free and immobilized cells in batch culture. Production of nutraceuticals was high in spray dried powder prepared from immobilized cell cultures. Nostochopsis lobatus showed superiority over rest of the species with respect to bilipigments, δ-ALA, nutritive value, antioxidant capacity, and ascorbate oxidase (APX) activity. Antioxidative capacity of phycobiliproteins extracted from these cyanobacteria (121.15 μM TE/g, Nostoc verrucosum to 217.62 μM TE/g, Nostochopsis lobatus) was invariably higher than those observed for higher plant sources and substantially increased under immobilized cell culture condition. Antioxidative enzyme, ascorbate oxidase remained stable in dry food preparations with considerably high activity under immobilized cell preparations (APXmax, 3.40 μmol/min/mg chlorophyll). These observations have important connotations in light of upcoming food and nutraceutical industries in the global market. Use of immobilized cells in batch culture could be an effective approach for scaling up production for commercial use.  相似文献   

9.
A new species, Sulawesifulvius indicus sp. n., is described from Bangalore, India. It is easily separated from the type species Sulawesifulvius schuhi Gorczyca et al., 2004, the only other species of the genus, by the small size, dorsal coloration, and the male genital structures. The discovery of a new species of Sulawesifulvius in southern India considerably extends the distribution of the genus, previously recorded only from Sulawesi, Indonesia.  相似文献   

10.
The Giant African Snail (Achatina fulica) is considered to be one the world’s 100 worst invasive alien species. The snail has an impact on native biodiversity, and on agricultural and horticultural crops. In India, it is known to feed on more than fifty species of native plants and agricultural crops and also outcompetes the native snails. It was introduced into India in 1847 and since then it has spread all across the country. In this paper, we use ecological niche modeling (ENM) to assess the distribution pattern of Giant African Snail (GAS) under different climate change scenarios. The niche modeling results indicate that under the current climate scenario, Eastern India, peninsular India and the Andaman and Nicobar Islands are at high risk of invasion. The three different future climate scenarios show that there is no significant change in the geographical distribution of invasion prone areas. However, certain currently invaded areas will be more prone to invasion in the future. These regions include parts of Bihar, Southern Karnataka, parts of Gujarat and Assam. The Andaman and Nicobar and Lakshadweep Islands are highly vulnerable to invasion under changed climate. The Central Indian region is at low risk due to high temperature and low rainfall. An understanding of the invasion pattern can help in better management of this invasive species and also in formulating policies for its control.  相似文献   

11.
Stepwise multiple discriminant analysis was applied to a two year water quality monitoring study of the Buckingham Canal at Madras, India. The variables were divided into
  1. physical and chemical
  2. pollutants; and
  3. biological
to test which group is efficient in discriminating stations which differ in water quality. Biological variables obtained higher loadings on the discriminant functions than the other two groups. The derived discriminant functions were tested for their discriminating power through the classification phase with the same raw data. The \lsHit and Misses\rs tables of classification indicate that 81.660% of the samples were correctly classified by the biological variables, against only 46.660% of the samples in the case of physical and chemical variables and 48.33% in the case of pollutants.  相似文献   

12.
13.
The ammonoid subfamily Peltoceratinae is a well-constrained group restricted to the Middle Upper Jurassic; it had a near global distribution. In Kutch (India), they were the most important marine macroinvertebrate group during the upper Callovian–lower Oxfordian. Previous reports suffered from excessive splitting due to failure to account for the large intraspecific variability and sexual dimorphism of these ammonoids. The present systematic revision, based on numerous specimens including many near-complete adult specimens, enables to recognize and describe three species of the genus Peltoceras (P. athleta, P. ponderosum, and P. kumagunense) and two species of the genus Peltoceratoides (P. semirugosus and P. propinquus), as well as identifying their macroconchs and microconchs. We rediscovered Peltoceras athleta, which was previously described by Waagen (1875) but often overlooked by subsequent workers. We were able to identify several morphs within this species that are stunningly similar with those previously reported from France. The presence of P. athleta sensu stricto prompted us to reinstate the Athleta Zone in Kutch, improving intercontinental biostratigraphic correlation. Also, it highlights that the genus Peltoceras has a different biostratigraphic longevity in Kutch: in Europe it is restricted to the upper Callovian, whereas in India it also occurs in the lower Oxfordian.  相似文献   

14.
《Comptes rendus biologies》2019,342(9-10):323-329
A new species of natricid snakes, Trachischium apteii sp. nov. is described from the northeastern Indian State of Arunachal Pradesh. The new species differs from its congeners in the following suite of characters: dorsal scales in 15:15:15 rows, SVL 293–299 mm, higher ventral count 143–150, very faint dorsal longitudinal lines, absence of yellow patch on the neck and the belly being pale yellow. Preliminary discussion on the phylogenetic position of the members of the genus Trachischium is presented. This discovery of a new snake species advocates the need for dedicated surveys to document biodiversity across Arunachal Pradesh and the neighbouring States of northeastern India.  相似文献   

15.
The racemic total synthesis of elegansidiol, farnesiferol B, and farnesiferol D has been obtained following a Diels–Alder approach. Gillman addition, cross metathesis reaction are the other key steps involved in the target synthesis.  相似文献   

16.
Summary The results of the limnological investigations of Swetganga, one of the thermal springs of Bakreswar, West Bengal, India, have formed the basis of this paper. The samples of water were collected eleven times from the month of September '67 to October '68 at regular intervals for analysis. The physical conditions like depth, temperature and chemical factors like pH, free carbon dioxide, phenolphthalein alkalinity, total alkalinity, total hardness, chloride, nitrite, nitrate, phosphate, silicate and dissolved oxygen were determined. A qualitative and quantitative analysis of plankton was also made.The water of the Kund was found to be distinctly alkaline on all occasions. Since free carbon dioxide was absent in all samples, phenolphthalein alkalinity was always recorded in appreciable quantities.The lower values of chloride were noted only during the monsoon months due to the dilution of water by the rain. The silicate content showed erratic fluctuations. Large amounts of phosphate were always present in the Kund. The absence of nitrite and traces of nitrate throughout, is a characteristic feature of this thermal spring.An attempt has been made, whenever possible, to attribute the reason of the changes and also to correlate the plankton blooms with the chemical factors. The coefficient of correlation between total alkalinity and phytoplankton (–0.529) indicates a negative correlation, significant at the 10 per cent level. No significant relation between phytoplankton and pH values (r = 0.183) has been observed. An apparent inverse relation between dissolved oxygen and phytoplankton has been noted.A list of phytoplankton and zooplankton has been incorporated. Total phytoplankton varied between 8.91 per cent and 100 per cent and the zooplankton between nil and 91.08 per cent of the total plankton bulk.  相似文献   

17.
Almost all ascidian larvae bear three mucus secreting and sensory organs, the adhesive papillae, at the anterior end of the trunk, which play an important role during the settlement phase. The morphology and the cellular composition of these organs varies greatly in the different species. The larvae of the Clavelina genus bear simple bulbous papillae, which are considered to have only a secretory function. We analysed the adhesive papillae of two species belonging to this genus, C. lepadiformis and C. phlegraea, by histological sections and by immunolocalisation of β-tubulin and serotonin, in order to better clarify the cellular composition of these organs. We demonstrated that they contain at least two types of neurons: central neurons, bearing microvilli, and peripheral ciliated neurons. Peripheral neurons of C. lepadiformis contain serotonin. We suggest that these two neurons play different roles during settlement: the central ones may be chemo- or mechanoreceptors that sense the substratum, and the peripheral ones may be involved in the mechanism that triggers metamorphosis.Key words: Settlement, neurotransmitter, serotonin, β-tubulin, papillary nerves, metamorphosis.Ascidians (phylum Chordata; subphylum Tunicata) are sessile filter-feeding organisms that can be found in all benthic marine environments and develop through a swimming tadpole larva. Larvae of colonial ascidians have a short planktonic life that can vary from minutes to hours (Burighel and Cloney, 1997). Prior to metamorphosis, the larva attaches to the substratum by means of peculiar organs of ectodermic origin, located in the anterior region of the trunk. These organs, known as adhesive papillae, secrete sticky substances and effect primary adhesion of the larva to the substrate (Cloney, 1977). They have an important role in the initiation of settlement and metamorphosis and there is evidence that, at least in some species, they participate in substrate selection (Torrence and Cloney, 1983; Svane and Young, 1989; Groppelli et al., 2003). In many species, they are organised in a triangular field, whereas in others they are aligned along the mid-sagittal plane of the trunk. Adhesive papillae have been classified into two types: eversible papillae, typical of some colonial species, composed by several cell types and rapidly changing shape as they touch the substrate, and non-eversible papillae, typical of solitary species, which do not change shape after settlement (Burighel and Cloney, 1997).With few exceptions, all adhesive papillae are formed by elongated secretory and sensory cells, which are recognised as primary neurons (Cloney, 1977, 1979). It has been proposed that sensory cells may detect the chemical and physical characteristics of the substratum at potential sites for settlement and metamorphosis (Young and Braithwaite, 1980; Groppelli et al., 2003).The presence of primary neurons in the papillae has been reported in the larvae of several species such as Distaplia occidentalis, Diplosoma macdonaldi, Phallusia mammillata, Ciona intestinalis and Ascidia malaca (Cloney, 1977;Torrence and Cloney, 1983; Sotgia et al., 1998; Takamura, 1998; Gianguzza et al., 1999).These neurons have axons that join together to form the papillary nerves that enter the central nervous system at the level of the sensory vesicle (Imai and Meinertzhagen, 2007).Recently, different neurotransmitters have been localised in the sensory neurons of the papillae of different species. The presence of GABAergic neurons has been reported in the papillae of Ciona savygni (Brown et al., 2005) and of Ciona intestinalis (Zega et al., 2008), while serotonergic neurons have been localised in the papillae of Phallusia mammillata (Pennati et al., 2001) and Botrylloides leachi (Pennati et al., 2007). Moreover, it has been demonstrated that serotonin plays a role in the mechanism triggering metamorphosis in ascidians (Zega et al., 2005).After attachment, all papillae retract to draw the larva closer to the substratum. In the colonial ascidian Distaplia occidentalis, the process of retraction is reversibly inhibited by cytochalasin B, suggesting that microfilaments are involved in this process (Cloney, 1979).Clavelina lepadiformis is a colonial species, whose larvae bear non-eversible simple bulbous papillae.They have been described as being formed only by columnar glandular cells, whose secreted material is responsible for the sticky properties of the organ. These papillae do not contain sensory cells and were considered the simplest among those studied (Turon, 1991).In this work, the morphology of the adhesive papillae of C. lepadiformis and C. phlegraea was further investigated by histological analysis and immunolabelling techniques in order to clarify the actual cellular composition and function of these organs.  相似文献   

18.
Summary

The life cycle of the Batrachospermales (freshwater florideophyte red such as Batrachospermum, Lemanea) is a shortened variant of the ‘normal’ marine florideophyte life cycle. The perennial Chantransia diploid phase is microscopic and encrusting. Each winter it produces one or more semi-erect haploid gametophytes by vegetative meiosis. Gamete production and fertilization is followed by production of diploid carposporophytes; these produce diploid carpospores which disperse, and regenerate the Chantransia phase. The question of the extent to which the Chantransia phase contributes resources to the gametophyte was approached by physiological-hydrodynamic modelling. These computations suggest that the photosynthetic rates in situ on an area basis are 20 times greater for the gametophyte than the Chantransia phase; this agrees with the observed ratios of peak biomass. The conclusion is that the Chantransia phase has a negligible role in provisioning the growing gametophyte, and that the role of the Chantransia phase is to occupy space with living biomass throughout the year, including exposure at summer drawdown, and (perhaps) by dispersal via production of monospores. A similar conclusion is arrived at on the basis of biomass data for the role of the perennial ‘mushroom’ phase of the semelparous marine Fucalean brown alga Himanthalia elongata in relation to the short-lived but much larger reproductive receptacles.  相似文献   

19.
Tordyliopsis brunonis (Apiaceae) is cytologically investigated here for the first time from India. The chromosome count of 2n = 33, ascertained here, represents a new intraspecific triploid cytotype in the species, supplementing the earlier report of a diploid cytotype with 2n = 22 from Nepal Himalayas. The diploid chromosome count (n = 11) has also been found in some of the presently investigated individuals which showed perfectly normal meiosis with 100 % pollen fertility and normal seed set. However, the individuals with triploid chromosome count showed irregular meiotic behaviour and abnormal microsporogenesis resulting in high pollen sterility (56.26 %) and no seed set. The irregular meiotic behaviour in the triploid individuals is attributed to the occurrence of variable number of univalents (1–7) at diakinesis and metaphase-I. In the subsequent meiotic stages, these univalents lagged at anaphases and constituted micronuclei in sporads. The triploid plants were also observed for natural propagation and it was noticed that no seeds were set. These plants were noticed to propagate vegetatively by rootstocks. Chromosomal pairing in triploid cytotype is typical of an allopolyploid. Based on the characterization of chromosomal pairing during meiosis, we assumed that the triploid individuals are probably alloploid in nature. Hypotheses concerning the possible origin of allotriploid in T. brunonis are also discussed.  相似文献   

20.
Heteropternis raipurensis n. sp. is described from Barnawapara Wildlife Sanctuary (Raipur, Chhattisgarh, India), and compared to H. respondens (Walker, 1859). An identification key to Asian species of Heteropternis is provided.  相似文献   

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