Development of reproductive structures in the sole Indian species of Hydatellaceae, Trithuria konkanensis, and its morphological differences from Australian taxa

2010 ◽  
Vol 23 (4) ◽  
pp. 217 ◽  
Author(s):  
Dmitry D. Sokoloff ◽  
Margarita V. Remizowa ◽  
Shrirang R. Yadav ◽  
Paula J. Rudall

The current paper presents new morphological and developmental data on the sole Indian species of Hydatellaceae, T. konkanensis Yadav & Janarthanam, and explores its morphological differences from Australian members of the family. On the basis of morphology and ecology, T. konkanensis appears to be closely related to T. lanterna, a species from tropical northern Australia that resembles T. konkanensis more closely than does any other Australian taxon. However, fruits are dehiscent in T. lanterna and indehiscent in T. konkanensis. Developmental data on T. konkanensis are significant for interpreting the reproductive units in Hydatellaceae. In T. konkanensis, each reproductive unit consists of two bract-like phyllomes, several carpels and a single central stamen that is initiated before the carpels. The earliest-formed carpels are those closest to the stamen; the latest-formed carpels are closest to the phyllomes. Despite their apparently whorled arrangement, the phyllomes are initiated sequentially. The spatial arrangement of the earliest-initiated carpels makes it unlikely that the phyllomes subtend any axillary structures. So far, there is no robust direct evidence in favour of a multiaxial (pseudanthial) morphological interpretation of bisexual reproductive units of Hydatellaceae. No evidence for dichogamy is present in bisexual reproductive units of either Indian or Australian Hydatellaceae, a feature that contrasts with the common presence of protogyny in flowers of other early divergent extant angiosperms.

2018 ◽  
Vol 31 (3) ◽  
pp. 209 ◽  
Author(s):  
Richard J. Dimon ◽  
Jiri Váňa ◽  
Alfons Schäfer-Verwimp ◽  
Jochen Heinrichs ◽  
Matt A. M. Renner

Molecular evidence supports the transfer of Conoscyphus Mitt. from Lophocoleaceae to Acrobolbaceae, which is unexpected on the basis of morphological evidence and further disrupts the morphological circumscription of Acrobolbaceae. Conoscyphus differs from other Acrobolbaceae in possessing a stem perigynium and a conspicuous perianth that forms a tube, large underleaves that produce rhizoids in a fascicle from the underleaf disc, and shoots that grow inverted when hanging free from the substrate. However, Conoscyphus shares with other Acrobolbaceae granular brown oil bodies, a multistratose capsule, absence of terminal branching and papillose leaf cell-surface ornamentation. To reflect the morphological differences, particularly in post-fertilisation reproductive structures, between Conoscyphus and other members of the family, we retain subfamily Conoscyphoideae and transfer it to Acrobolbaceae.


2016 ◽  
Vol 1 (1) ◽  
Author(s):  
D.G. Shah ◽  
D.N. Mehta ◽  
R.V. Gujar

Bryophytes are the second largest group of land plants and are also known as the amphibians of the plant kingdom. 67 species of bryophytes have been reported from select locations across the state of Gujrat. The status of family fissidentaceae which is a large moss family is being presented in this paper. Globally the family consists of 10 genera but only one genus, Fissidens Hedw. has been collected from Gujarat. Fissidens is characterized by a unique leaf structure and shows the presence of three distinct lamina, the dorsal, the ventral and the vaginant lamina. A total of 8 species of Fissidens have been reported from the state based on vegetative characters as no sporophyte stages were collected earlier. Species reported from the neighboring states also showed the absence of sporophytes. The identification of different species was difficult due to substantial overlap in vegetative characters. Hence a detailed study on the diversity of members of Fissidentaceae in Gujarat was carried out between November 2013 and February 2015. In present study 8 distinct species of Fissidens have been collected from different parts of the state. Three species Fissidens splachnobryoides Broth., Fissidens zollingerii Mont. and Fissidens curvato-involutus Dixon. have been identified while the other five are still to be identified. Fissidens zollingerii Mont. and Fissidens xiphoides M. Fleisch., which have been reported as distinct species are actually synonyms according to TROPICOS database. The presence of sexual reproductive structures and sporophytes for several Fissidens species are also being reported for the first time from the state.


2020 ◽  
Vol 12 (17) ◽  
pp. 17374-17379
Author(s):  
W.G.D. Chathuranga ◽  
K. Kariyawasam ◽  
Anslem De Silva ◽  
W.A.Priyanka P. De Silva

We investigated the impact of dipteran predators on eggs in foam nests of the Common Hour-glass Tree Frog Polypedates cruciger Blyth, 1852 (Anura: Rhacophoridae) in central Sri Lanka.  Foam nests (n=24) of P. cruciger were examined at their natural breeding habitats and infected (n=8) and uninfected spawns (n=16) were identified.  Emerging tadpoles were collected in a water container hung under each spawn and the average number of tadpoles (N) hatched from infected spawns (N=0) was compared with that of uninfected spawns (N=354 ± 67).  Three severely infected spawns were brought to the laboratory and the fly larvae were reared until they metamorphosed to adults.  Morphological and molecular identification of the flies confirmed them as belonging to Caiusa testacea Senior-White, 1923 of the family Calliphoridae.  The infected spawns were completely destroyed and an estimated average of 400 P. cruciger eggs per spawn were lost.  The results revealed a high impact of Caiusa testacea on egg and embryo mortality of P. cruciger.


Mathematics ◽  
2021 ◽  
Vol 9 (16) ◽  
pp. 1835
Author(s):  
Antonio Barrera ◽  
Patricia Román-Román ◽  
Francisco Torres-Ruiz

A joint and unified vision of stochastic diffusion models associated with the family of hyperbolastic curves is presented. The motivation behind this approach stems from the fact that all hyperbolastic curves verify a linear differential equation of the Malthusian type. By virtue of this, and by adding a multiplicative noise to said ordinary differential equation, a diffusion process may be associated with each curve whose mean function is said curve. The inference in the resulting processes is presented jointly, as well as the strategies developed to obtain the initial solutions necessary for the numerical resolution of the system of equations resulting from the application of the maximum likelihood method. The common perspective presented is especially useful for the implementation of the necessary procedures for fitting the models to real data. Some examples based on simulated data support the suitability of the development described in the present paper.


Zootaxa ◽  
2021 ◽  
Vol 4990 (1) ◽  
pp. 192-200
Author(s):  
SIMONE MARIA DE ALBUQUERQUE LIRA ◽  
CYNTHIA DAYANNE MELLO DE LIMA ◽  
IGOR DE ÁVILA TEIXEIRA ◽  
RALF SCHWAMBORN

The objective of this paper is to describe and illustrate the first zoeal stage of the largest land crab of the Tropical Atlantic, Johngarthia lagostoma (Milne Edwards, 1837) (Brachyura: Gecarcinidae). A larval description of J. lagostoma was previously not available. Larvae were obtained from ovigerous females on Rocas Atoll and Fernando de Noronha Archipelago, Brazil. Twenty larvae were randomly chosen to be dissected and described in detail, while 40 others (20 larvae from each island) were measured only. The published description of the congener J. planatus (Stimpson, 1860) larvae was used for a comparison of larval morphology. Some morphological differences between the first zoeal stage of these two species were: The absence or presence of a simple shorter seta on antennule, number of the minute terminal spines on the antenna, setation of the coxal endite of the maxilla, exopod unsegmented of the first and second maxilliped, and a single mid-dorsal seta on first pleonite. These results and differences observed between these species can assist in studies on phylogenetic relationships within the Family Gecarcinidae MacLeay, 1838, as well as in the identification of the larvae of J. Lagostoma in plankton samples from the tropical Atlantic.  


2021 ◽  
Vol 2 (1) ◽  

Covid 19 being a pandemic has uniformly and bizarrely affected the globe in a most unpredictable manner. So it becomes very important to unravel the transmission dynamics and the effect of the virus which has made it a deadly virus so far. Covid 19 is a member of coronavirus family, which also includes the SARS virus (Severe Acute Respiratory Syndrome) and MERS (Middle East Respiratory Symptoms) virus. The family of Coronavirus includes virus strains that the common cold and flu are caused [1].


Author(s):  
P.R. Bigelow ◽  
C.G. Alexander

Two species of large extension feeding barnacles are abundant on exposed tropical rocky shores of northern Australia. The cirri of many specimens carry varying numbers of a commensal diatom in some cases with as many as 2000 individuals on a single cirrus. The araphid diatom resembles the genus, Lichmophora within the family Fragilariaceae although no description has yet been published. Species of Lichmophora are common benthic diatoms in these waters as an epiphyte on macroalgae and common primary fouling diatoms on test panels. The diatom reported here has not been found on any substratum other than the barnacles Tetraclita squamosa and Australobalanus imperator, very rarely on Balanus amphitrite. Analysis of the diatom distribution on the cirri shows significantly higher numbers on the posterior captorial cirri. The effect of commensal diatoms on the feeding efficiency of the barnacles is discussed.


2012 ◽  
Vol 562-564 ◽  
pp. 2084-2087
Author(s):  
Hui Ding ◽  
Xu Yang Lou

This paper addresses stability properties of linear switched positive systems composed of continuous-time subsystems and discrete-time subsystems. Based on the common linear copositive Lyapunov functions, stability of the positive systems is discussed under arbitrary switching. Moreover, a sufficient condition on the minimum dwell time that guarantees the stability of linear switched positive systems. The dwell time analysis interprets the stability of linear switched positive systems through the distance between the eigenvector sets. Thus, an explicit relation in view of stability is obtained between the family of the involved subsystems and the set of admissible switching signals.


Artifex Novus ◽  
2019 ◽  
pp. 58-75
Author(s):  
Anna Sylwia Czyż

ABSTRAKT Sprowadzone do Wilna między 1616 a 1618 r. benedyktynki utworzyły niewielką i skromnie uposażoną wspólnotę. Ich sytuacja zmieniła się w 1692 r., kiedy to dzięki bogatym zapisom Feliksa Jana Paca mogły wystawić murowany kościół konsekrowany w 1703 r. Hojność podkomorzego litewskiego nie była przypadkowa, bowiem do wileńskich benedyktynek wstąpiły jego córki Sybilla i Anna, jedyne potomstwo jakie po sobiepozostawił. Z nich szczególne znaczenie dla dziejów klasztoru miała Sybilla (Magdalena) Pacówna, która w 1704 r. została wybrana ksienią. Nie tylko odnowiła ona życie wspólnoty, ale stała się również jedną z najważniejszych postaci ówczesnego Wilna. Po pożarze w 1737 r. Sybilla Pacówna energicznie przystąpiła do odbudowy klasztoru i kościoła, którą kończyła już jej następczyni Joanna Rejtanówna. Wzniesioną wówczas według projektu Jana Krzysztofa Glaubitza fasadę ozdobiono stiukowo-metalową dekoracją o indywidualnie zaplanowanym programie ideowym odwołującym się i do tradycji zakonnej i rodowej – pacowskiej. W fasadzie wyeksponowano ideały związane z życiem benedyktyńskim sytuując je wśród aluzji o konieczności walki na płaszczyźnie ducha i ciała, włączając w militarną symbolikę także konieczność walki z wrogami Kościoła i ojczyzny oraz charakterystyczną dla duchowości benedyktyńskiej pobożność związaną z krzyżem w typie karawaka oraz zOpatrznością Bożą. Jednocześnie przypominano o bogactwie powołań w klasztorze benedyktynek wileńskich przyrównując mniszki do lilii. Porównanie to dzięki obecności w fasadzie herbu Gozdawa (podwójna lilia) oraz powszechnego w XVII i XVIII w. zwyczaju określania Paców „Liliatami” można było odnosić także do ich rodu, w tym do zasłużonej dla klasztoru ksieni Sybilli. Tak mocne wyeksponowanie fundatorów było nie tylko chęciąupamiętnia darczyńców, ale wraz z całym architektonicznym i plastycznym wystrojem świątyni wiązało się z koniecznością stworzenia przeciwwagi dla nowego i prężnie rozwijającego się pod patronatem elity litewskiej klasztoru Wwizytek w Wilnie. Przy tym charakter dekoracji fasady kościoła pw. św. Katarzyny wpisuje się w inne fundacje Paców: kościół pw. św. Teresy i kościół pw. śś. Piotra i Pawła będąc ostatnią ważną inicjatywą artystyczną rodu w stolicy Wielkiego Księstwa Litewskiego. SUMMARY The Benedictines, who had been brought to Vilnius between 1616 and 1618, formed a small and modest community. Thanks to the generous legacy of Feliks Jan Pac, in 1692 their situation changed as they could erect a brick church, which was then consecrated in 1703. The generosity of the Lithuanian chamberlain was not a coincidence; his two daughters, Sybilla and Anna, the only offspring he left, had joined the Benedictine Sisters in Vilnius. Sybilla (Magdalena) Pac, who became an abbess in 1704, was particularly important for the history of the monastery. Not only did she renew the community life, but she also became one of the most important personalities of the then Vilnius. After the fire in 1737 Sybilla Pac vigorously started rebuilding the monastery and the church, which was completed by her successor, Joanna Rejtan. The facade which was then erected after Johann Christoph Glaubitz’s design was adorned with stucco and metal decorations with a perfectly devised ideological programme which referred to the tradition of the order and to the one of the Pac family. The facade presented ideals connected with the Benedictine life, which placed them among the hints of having to fight at the level of spirit and body, incorporating among the military symbols also the need to fight the enemies of the Church and the state, and the typical for the Benedictine spirituality piety connected with the Caravaca cross and the Divine Providence. At the same time, it reminded of the Benedictine vocations comparing nuns to lilies. This comparison, due to the presence of the Gozdawa coat-of-arms (double lilie) and the common nickname of the Pac family in the 17th and 18th cc. “the Liliats”, could also apply to their lineage, including the abbess Sybilla and her services to the monastery. Exposing founders in such an emphatic way was not only the will to immortalise them, but was also, together with the entire architectural and artistic decor of the church, connected with the need to counterbalance the new and dynamicallydeveloping Visitation Monastery in Vilnius. At the same time, the nature of the facade decoration of the Church of St. Catherine is in line with other foundations of the Pac family: St Theresa’s Church and the St Peter and St Paul Church, and was the last significant artistic initiative of the family in thecapital of the Grand Duchy of Lithuania


Author(s):  
Ai-Ling Yang ◽  
Lin Chen ◽  
Kai Fang ◽  
Xing-Fan Dong ◽  
Yu-Xuan Li ◽  
...  

To determine if Ageratina adenophora can accumulate diverse pathogens from surrounding native plants, we intensively sampled fungal communities, including endophytes, leaf spot pathogens and canopy air fungi, associated with Ag. adenophora as well as native plants in its invasive range. In total, we collected 4542 foliar fungal strains from 10 geographic sites, including 1340 from healthy leaves of Ag. adenophora, 2051 from leaf spots of Ag. adenophora and 1151 from leaf spots of 56 species of native plants and crops. Taxonomically, the common fungal genera included Colletotrichum, Diaporthe, Alternaria, Nemania, Xylaria, Neofusicoccum, Nigrospora, Epicoccum, Gibberella, Pestalotiopsis, Irpex, Schizophyllum and Clonostachys. We also isolated the cultivable fungi from 12 air samples collected from six areas in Yunnan Province, PR China. Among the total of 1255 air fungal isolates, the most common genera were Cladosporium, Trichoderma and Epicoccum. Among them, two new Remotididymella species, Remotididymella ageratinae from leaf spot of Ag. adenophora and Remotididymella anemophila from canopy air of Ag. adenophora were found. The two species showed both asexual and sexual reproductive structures. The conidia of R. ageratinae and R. anemophila are larger than those of R. anthropophila and R. destructiva. The size of ascospores of R. ageratinae and R. anemophila also differ from R. bauhiniae. Phylogenetic analysis of the combined ITS, LSU rRNA, rpb2 and tub2 sequences showed that R. ageratinae and R. anemophila each formed a distinct clade, separated from all species previously described in Remotididymella and confirmed them as new species belonging to Remotididymella. Full descriptions of R. ageratinae and R. anemophila are provided in this study.


Sign in / Sign up

Export Citation Format

Share Document