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1.
Sci Adv ; 8(13): eabm7452, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35353568

RESUMEN

Phylogenetic relationships and the timing of evolutionary events are essential for understanding evolution on longer time scales. Cheilostome bryozoans are a group of ubiquitous, species-rich, marine colonial organisms with an excellent fossil record but lack phylogenetic relationships inferred from molecular data. We present genome-skimmed data for 395 cheilostomes and combine these with 315 published sequences to infer relationships and the timing of key events among c. 500 cheilostome species. We find that named cheilostome genera and species are phylogenetically coherent, rendering fossil or contemporary specimens readily delimited using only skeletal morphology. Our phylogeny shows that parental care in the form of brooding evolved several times independently but was never lost in cheilostomes. Our fossil calibration, robust to varied assumptions, indicates that the cheilostome lineage and parental care therein could have Paleozoic origins, much older than the first known fossil record of cheilostomes in the Late Jurassic.

2.
Proc Biol Sci ; 288(1959): 20211632, 2021 09 29.
Artículo en Inglés | MEDLINE | ID: mdl-34547910

RESUMEN

Examining the supposition that local-scale competition drives macroevolutionary patterns has become a familiar goal in fossil biodiversity studies. However, it is an elusive goal, hampered by inadequate confirmation of ecological equivalence and interactive processes between clades, patchy sampling, few comparative analyses of local species assemblages over long geological intervals, and a dearth of appropriate statistical tools. We address these concerns by reevaluating one of the classic examples of clade displacement in the fossil record, in which cheilostome bryozoans surpass the once dominant cyclostomes. Here, we analyse a newly expanded and vetted compilation of 40 190 fossil species occurrences to estimate cheilostome and cyclostome patterns of species proportions within assemblages, global genus richness and genus origination and extinction rates while accounting for sampling. Comparison of time-series models using linear stochastic differential equations suggests that inter-clade genus origination and extinction rates are causally linked to each other in a complex feedback relationship rather than by simple correlations or unidirectional relationships, and that these rates are not causally linked to changing within-assemblage proportions of cheilostome versus cyclostome species.


Asunto(s)
Briozoos , Fósiles , Animales , Biodiversidad , Evolución Biológica , Filogenia
3.
Fish Shellfish Immunol ; 107(Pt A): 118-128, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32961293

RESUMEN

Biofloc technology is increasingly becoming the most promising aquaculture tool especially in places where water is scarce and the land is very expensive. The dynamics of water quality, as well as plankton and microbial abundance, are collectively necessary for successful fish farming. The prospective use of jaggery as a potential carbon source and its influence on water quality, growth performance, innate immunity, serum bactericidal capacity, and disease resistance to Aeromonas hydrophila was investigated in Oreochromis niloticus. A completely randomized design was used in triplicates, where the control group was reared in a water system with no carbon source, while T1, T2, and T3 groups were raised in biofloc systems at C:N ratios of C:N12, C:N15, and C:N20, respectively. Water specimens were collected daily and fortnightly, while blood, serum, and head kidneys were collected at 75 days of experimental period for further analysis. TAN, nitrite, and ammonia values were considerably reduced, while the TSS values elevated significantly in all treated groups compared to the control. Jaggery-based biofloc system (JB-BFT) has a pronounced effect on hematological and growth performance parameters rather than control. Similarly, serum antioxidants, lysozyme, protease, antiprotease and bactericidal capacity were significantly increased (p < 0.05) in the treated groups in a dose-dependent manner. LYZ, TNF-α, and IL-1ß genes were upregulated in proportion to C:N ratios with the highest fold in C:N20. Furthermore, fish treated with JB-BFT presented lower cumulative mortalities and better relative levels of production (RLP) after experimental challenge with A. hydrophila compared to control. In conclusion, JB-BFT has a robust influence on Nile tilapia (O. niloticus) innate immunity through favorable innovation of various immune-cells and enzymes as well as upregulating the expression levels of immune-related genes. This study offers jaggery as a new carbon source with unique properties that satisfy all considerations of biofloc technology in an eco-friendly manner.


Asunto(s)
Carbono/análisis , Cíclidos/inmunología , Resistencia a la Enfermedad , Enfermedades de los Peces/inmunología , Nitrógeno/análisis , Extractos Vegetales/administración & dosificación , Calidad del Agua , Aeromonas hydrophila/fisiología , Animales , Acuicultura/instrumentación , Cíclidos/genética , Cíclidos/crecimiento & desarrollo , Resistencia a la Enfermedad/efectos de los fármacos , Infecciones por Bacterias Gramnegativas/inmunología , Infecciones por Bacterias Gramnegativas/veterinaria , Tecnología
4.
Zootaxa ; 4486(3): 251-283, 2018 Sep 28.
Artículo en Inglés | MEDLINE | ID: mdl-30313746

RESUMEN

This paper describes 12 species of ctenostomes from the marine waters of the Korean Peninsula, including five new species-Alcyonidium bullitum n. sp., Alcyonidium pulposum n. sp., Alcyonidium busanensis n. sp., Immergentia cheongpodensis n. sp. and Penetrantia taeanata n. sp., the latter two constituting shell-borers that ramify within dead mollusk shells. Three previously described species are also newly added to the Korean fauna-Amathia acervata Lamouroux, 1824, Amathia medullaris Mawatari, 1972 and Walkeria prorepens Kubanin, 1992. The nomenclature of known species is updated and a revised checklist of all Korean Ctenostomata is included. New biological information is provided based on observation and microphotography of living and preserved colonies, SEM images of dry material and resin casts of ctenostome borings in mollusk shells.


Asunto(s)
Briozoos , Animales
5.
Carbohydr Polym ; 166: 329-337, 2017 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-28385240

RESUMEN

Vibrionaceae is bifolded drug resistant emerging pathogens, active in various aquaculture sectors especially in shrimp culture around the world. V. parahaemolyticus are most dreadful viral outbreaks to shrimp culture. During the last decade the shrimp production level has been increased and also accompanied with various diseases. In the present research bacterial cellulose (BC) membrane produced by Gluconacetobacter xylinus in cell suspension. Further, TEMPO (2,2,6,6-tetramethylpiperidine-1-oxyl radical) oxidation was done to activate carboxyl group subsequently, TEMPO oxidized BC immersed in AgNO3 solution to generate AgNP anchored with BC to increase vibriocidal activity. Investigation of pure BC, TEMPO-BC and AgNP deposited BC was done by scanning electron microscopy (SEM), energy-dispersive spectroscopy (EDS) and X-ray diffraction (XRD). Further vibriocidal effect was observed against the pathogen V. parahaemolyticus and V. harveyi. We found AgNP-BC more effective as compare pure BC, TEMP-BC, and AgNO3. Therefore AgNP deposited BC, is promising alternative to control the shrimp pathogen.


Asunto(s)
Celulosa Oxidada/química , Óxidos N-Cíclicos , Gluconacetobacter xylinus/química , Nanopartículas del Metal/química , Plata/farmacología , Vibrio/efectos de los fármacos , Antibacterianos/farmacología , Celulosa
6.
Zootaxa ; 3999: 125-34, 2015 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-26250330

RESUMEN

The Pirabas Formation in Brazil has been studied for many years and a great diversity of animal groups (in particular fishes, molluscs and echinoderms) have been described from there, whereas the Bryozoa have scarcely been mentioned. New samples, collected specifically to focus on bryozoans, have shown that the diversity in this formation is higher than previously thought. Here we describe two new species belonging to the cheilostomate genus Hippopleurifera--H. barbosae sp. nov. and H. confusa sp. nov. Both species were collected at Atalaia Beach, northeastern Pará state, which boasts some of the best marine Cenozoic fossil outcrops in Brazil. After accounting for all described species, plus the two new species and four generic reassignments (new combinations) described herein, some 29 Hippopleurifera species are now known. Most of these are fossils from Europe or the USA, but a handful are known from the Recent Mediterranean, Caribbean and Indo-West Pacific.


Asunto(s)
Briozoos/anatomía & histología , Briozoos/clasificación , Fósiles/anatomía & histología , Animales , Brasil , Briozoos/ultraestructura , Microscopía Electrónica de Rastreo , Especificidad de la Especie
7.
Zootaxa ; 3838(1): 98-112, 2014 Jul 16.
Artículo en Inglés | MEDLINE | ID: mdl-25081761

RESUMEN

Pirabasoporella gen. nov. is introduced for three new bryozoan species from the Early Miocene of the tropical western Atlantic. The genus is placed in the family Jaculinidae Zabala, a peculiar group of cheilostome bryozoans characterised by reticulate colonies formed by uni- or biserial branches that are connected by kenozooidal struts. This colonial morphology superficially resembles colonies of the Paleozoic order Fenestrata (Stenolaemata) and some Recent Cyclostomata. As jaculinid colonies are anchored to soft sediments via rhizoids, however, they differ in life habit from Paleozoic and modern fenestrate colonies, which are firmly attached to stable substrata by an encrusting base.        The three new species are Pirabasoporella atalaiaensis n. sp. from the Brazilian Pirabas Formation, Pirabasoporella baitoae n. sp. from the Baitoa Formation (Dominican Republic), and Pirabasoporella chipolae n. sp. from the Floridan Chipola Formation. Their presence in the Early Miocene western Atlantic represents the earliest record of Jaculinidae, and suggests that the origin of the family, the only living species of which are known from the eastern Atlantic and Mediterranean Sea, extends well into the Paleogene.        The Jaculinidae is here transferred from the lepraliomorph superfamily Schizoporelloidea Jullien to the umbonulomorph Lepralielloidea Vigneaux owing to the partly umbonuloid frontal shield and non-schizoporelloid ovicell.


Asunto(s)
Briozoos/clasificación , Estructuras Animales/anatomía & histología , Estructuras Animales/crecimiento & desarrollo , Animales , Tamaño Corporal , Brasil , Briozoos/anatomía & histología , Briozoos/crecimiento & desarrollo , Ecosistema
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