Search results for "Asteroidea"

Reproductive strategy as a piece of the biogeographic puzzle: a case study using Antarctic sea stars (Echinodermata, Asteroidea)

2017

13 pages; International audience; AimTo describe and analyse asteroid biogeographic patterns in the Southern Ocean (SO) and test whether reproductive strategy (brooder versus broadcaster) can explain distribution patterns at the scale of the entire class. We hypothesize that brooding and broadcasting species display different biogeographic patterns.LocationSouthern Ocean, south of 45 °S.MethodsOver 14,000 asteroid occurrences are analysed using bootstrapped spanning network (BSN), non-metrical multidimensional scaling (nMDS) and clustering to uncover the spatial structure of faunal similarities among 25 bioregions.ResultsMain biogeographic patterns are congruent with previous works based on…

New records of Asteraceae for the non-native flora of Tunisia and north Africa with some nomenclatural remarks

2022

International audience; Sixteen new Asteraceae are added to the non-indigenous flora of Tunisia. Six of them (Dimorphotheca ecklonis, Gaillardia pulchella, Gazania linearis var. linearis, Guizotia abyssinica, Rudbeckia triloba and Tithonia diversifolia) are also new for the flora of North Africa. Chrysanthemum morifolium is here first reported for the Mediterranean Basin. Seven genera (Argyranthemum, Bidens, Dimorphotheca, Gaillardia, Guizotia, Rudbeckia and Tithonia) are recorded for the first time for the vascular flora of Tunisia. Most of these species escaped from gardens and pots and became casual along roadsides and/or disturbed areas after cypsela dispersion (except for Chrysanthemum…

Morphological and molecular analysis of Henricia Gray, 1840 (Asteroidea: Echinodermata) from the Northern Atlantic Ocean

2017

Late Cretaceous echinoderm ‘odds and ends’ from the Low Countries

2018

From various levels within the Gulpen and Maastricht formations (upper lower to upper upper Maastrichtian, c. 69.5–66 Ma) in the extended type area of the Maastrichtian Stage (southeast Netherlands, northeast Belgium and the Aachen area in Germany), a few recent additions to echinoderm faunas are illustrated and briefly discussed. Added are some erratic, flint-preserved, pre-Maastrichtian echinoid taxa from Pleistocene fluvial gravel deposits; these are of palaeogeographical interest. Crinoids include the comatulid Semiometra saskiae with traces of sublethal predation and several bourgueticrinines. Amongst the latter, the species Dunnicrinus aequalis is found preserved in biocalcarenites as…

Relazioni tra parametri biometrici in Marthasterias glacialis (L.) (Asteroidea)

2013

Biometric parameters of the Asteroid echinoderm Marthasterias glacialis (L.) were measured at Ustica Island MPA (SW Tyrrhenian Sea). Wet weight was correlated with tip-to-tip (arm-span) diameter, central disk, arm length, arm width and arm height. Results show high positive correlation between weight and arm height, suggesting a new useful method to estimate starfish size also for in situ measurements.

A new genus and species of asteraceae-inhabiting aphid (hemiptera: aphididae) from Costa Rica and Mexico

2013

P. 323-331 Ucrimyzus villalobosi Mier Durante & Pérez Hidalgo gen. n., sp. n. (Hemiptera: Aphididae: Macrosiphini) are described from apterous and alate viviparous females collected on species of genera Bidens, Schkuhria, Senecio and Stevia (Asteraceae: Asteroideae) in Costa Rica and Mexico. Principal components analysis (PCA) was done to verify that the studied aphids belong to a single species regardless of their geographical origin or host plant. Molecular analyses were carried out on the sequences of a fragment of the mitochondrial gene encoding for cytochrome c oxidase subunit 1 (COI) and of a fragment of the nuclear gene encoding elongation factor 1α (EF1α). The taxonomic discussion t…

Modern pollen and non-pollen palynomorphs along an altitudinal transect in Jammu and Kashmir (Western Himalaya), India

2021

Pollen and non-pollen palynomorphs were analysed from 35 modern moss cushions collected along an altitudinal gradient (2225–2552 m a.s.l.) from the Baramulla District of Jammu and Kashmir State (Western Himalaya), India. The selected sampling altitude is at the elevation of appearance of blue pine (Pinus wallichiana) and West Himalayan spruce or morinda spruce (Picea smithiana). We used cluster analysis and principal component analysis (PCA) to reveal trends and characteristics in the modern pollen and non-pollen palynomorph composition within this zone. Tree taxa mainly correlated positively with the altitudinal gradient, i.e. tree pollen is more abundant at higher altitudes. The presence …

Correction to: Echinodermata: The complex immune system in echinoderms (Advances in Comparative Immunology, 10.1007/978-3-319-76768-0_13)

2018

This chapter was inadvertently published with an incorrect spelling of the author's name as V. Arriza whereas it should be V. Arizza. In addition to this the affiliation of one of the chapter authors Elisse Sutton was published incorrectly and it has now been corrected to read as Department of Biological Sciences, Macquarie University, Sydney, NSW, Australia.

A Middle Cambrian edrioasteroid from the Murero biota (NE Spain) with Australian affinities

2007

Abstract A Middle Cambrian edrioasteroid belonging to the genus Cambraster is described from the Middle Cambrian Murero biota (Cadenas Ibericas, NE Spain). Up to now, this genus was known only from Australia and France. This represents the first record of the class Edrioasteroidea in the Cambrian of Spain. Moreover, preliminary results on the diversity and biostratigraphic position of Cincta, Eocrinoidea and Edrioasteroidea from this area are reported.

Echinodermata: The complex immune system in echinoderms

2018

View references (418) The Echinodermata are an ancient phylum of benthic marine invertebrates with a dispersal-stage planktonic larva. These animals have innate immune systems characterized initially by clearance of foreign particles, including microbes, from the body cavity of both larvae and adults, and allograft tissue rejection in adults. Immune responsiveness is mediated by a variety of adult coelomocytes and larval mesenchyme cells. Echinoderm diseases from a range of pathogens can lead to mass die-offs and impact aquaculture, but some individuals can recover. Genome sequences of several echinoderms have identified genes with immune function, including expanded families of Toll-like r…