Echinodermata

In early 1992 the northern Pacific seastar, Asterias amurensis was identified from Tasmanian waters. It is possible that larvae may have been released in discarded ballast water from overseas ships. Each adult female may release up to 19,000,000 eggs annually. The species is a serious predator of accessible marine fauna, particularly bivalve molluscs. Little is known of the impact of A. amurensis on its northern hemisphere habitat. The seastars appear to be thriving in Tasmanian waters and vast numbers have been observed around the Hobart waterfront. Research by the Tasmanian Museum includes survey s of present distribution and abundance of the seastar, data about its physico-chemical environment, aspects of its reproductive biology, and the species on which it preys. Future management of this pent in Australia may well depend on the information provided by this research [Asterias amurensis. ballast water introductions. [Echinodermata, Asteroidea, aquaculture, alien species, Tasmania. Australia.]

The distribution and population density of Acanthaster planci (crown-of-thorns-starfish or COTS) in Sogod Bay, Southern Leyte, Central Philippines was assessed on July August,2012 using belt transects of 50-80 quadrats (5 x 5 m). Four sites were considered. Mean COTS density varied significantly among sampling sites, ranging from 0.4-5.2 starfishes/25 m2 corresponding to 160-2,080 starfishes/ha, an indication of an outbreak. On the other hand, the mean body size of  A. planci ranged from 13.7 32.4 cm, varied significantly among sampling sites and possibly belonging to different cohorts of COTS population within SogodBay. This suggests that outbreak could be due to progressive accumulation of COTS from multiple cohorts. At Adrian Reef Marine Sanctuary in Limasawa, COTS distributions were aggregated (Morisita’s Index of Dispersion = 2.6) and was significantly larger (32.4 cm) than the other sites. We believe that the aggregation at Adrian Reef Marine Sanctuary is a form of foraging behavior at this time of the year and not a preparation for mass spawning

The response of Acanthaster planci or crown-of-thorns starfish (COTS) to intracoelomic injection of hypersaline solutions was investigated to establish its potential application as A. planci population control especially during an outbreak. Adult A. planci when inverted had a normal righting response time (in seconds) of 163 ± 1 (mean ± SE; N ＝ 298). Injection of concentrated salt solutions led to negative effects on adult A. planci. The spines bent down, body collapsed and the starfish became comatose and died after 24-hours. The higher the salt concentration, the higher is the % comatose individuals. In addition, comatose specimens failed to recover with time. Mortality was highest at the highest treatment concentration with LC 90 of 285.3 and LC 99 of 383.2 ppt. The effects of time, salt concentration and its interaction(salt concentration x time) were significant (p ＝ 0.00). Theionic and osmotic disruption of the coelomic fluid canseriously affect physiological functions of the organismincluding neuromuscular activity. Thus, in the control of A. planci, concentrated salt solution can be used as a cheaper alternative to dry acid, acetic acid or m ammoniumhydroxide, all of which are expensive, may not be locally available and not environment friendly

Le Sud du Maroc recèle un incomparable ensemble d'archives paléontologiques sur les premiers développements de la Vie durant près de 180 millions d'années. Au travers d'illustrations somptueuses, servies par un texte remarquablement documenté, l'auteur met en scène de véritables "pépites paléontologiques" patiemment exhumées par les collecteurs locaux et les paléontologues. Ce splendide ouvrage nous entraîne dans un monde extraordinaire, véritable repaire "d'aliens fossiles" aux morphologies les plus improbables ! Plus de 950 photos et illustrations pour un périple paléontologique dans le Sud du Maroc. Morocco contains an incomparable collection of palaeontological archives on the early development of life for nearly 180 million years. Through sumptuous illustrations, served by a remarkably documented text, the author describes and illustrates true "paleontological nuggets" patiently exhumed by local collectors and palaeontologists. This splendid work leads us into an extraordinary world, a true haunt of "fossil aliens" with the most improbable morphologies! More than 950 photos and illustrations for a palaeontological journey in Southern Morocco Southern. « My compliments on the massive and impressive work. This will surely be a book discussed and loved by many. I am excited to be among the first people to read it. » Allart van Viersen (Natuurhistorisch Museum Maastricht) « Un ouvrage de référence remarquablement documenté et superbement illustré sur les fossiles du Paléozoïque marocain : le "paradis des géologues" possède désormais sa Bible! » Bertrand Lefebvre (CNRS, Université Lyon 1)

Turkey is surrounded by four seas with different hydrographical characteristics and TSS (Çanakkale Strait, Sea of Marmara and İstanbul Strait) serve both as a biological corridor and barrier between the Aegean and Black Seas (Öztürk and Öztürk, 1996). Among the 92 echinoderm species (two Crinoidea, 24 Asteroidea, 24 Ophiuroidea, 20 Echinoidea and 22 Holothuroidea) reported from Turkey, 65 (two Crinoidea, 17 Asteroidea, 17 Ophiuroidea, 18 Echinoidea and 11 Holothuroidea) were reported from the TSS. The number of echinoderm species in the coasts of the TSS also varies due to the different biotic environments.

Hewan dalam rangka memenuhi kebutuhannya akan energy (ATP) menyelenggarakan berbagai reaksi metabolisme, akan tetapi tidak hanya menghasilkan ATP dan zat-zat yang bermanfaat lainnya melainkan juga menghasilkan zat sisa, yang tidak digunakan lagi didalam tubuh, dan harus dikeluarkan melalui sistem yang disebut dengan sistem ekskresi atau sistem pengeluaran untuk menjaga konsep homeostatis dalam tubuh.

Acanthaster planci commonly known as crown-of-thorns starfish (COTS) is a natural predator of hermatypic corals, and it controls fast growing corals like species of Acropora. However, when the density of COTS on a reef reaches such levels that corals are being consumed faster than they can grow-termed as 'outbreak"-then that is the time to engage in controlling COTS population in order to protect and conserve coral communities where fishing and tourism industry like in the Philippines depends on it. The goal of COTS population control techniques is to regulate COTS population outbreak in developing country like the Philippines using environment-friendly, cheap and safe methods. The process of COTS Population control techniques and management strategies includes: 1) baseline information or assessment of COTS population and distribution including spawning season, 2) coordination, and 3) planning with the different stakeholders including the local government units and business sectors, and 4) implementation of COTS population control techniques using cheap concentrated salt solution using improvised COTS gun that is easy to make and install. The total cost for the first operation is PhP 3492.00 or PhP 2.03/starfish, and this will reduce into PhP 1,160.00 PhP 1.2/starfish in the next operation. This is cheaper than bounty system of PhP 5.00-10.00/starfish in Caohagan Island and Sogod Bay, Southern Leyte and SCUBA Diving using dry acid with Veldspar Spot Gun of about PhP 10,050.00 0r PhP 41.00/starfish for the equipment and dry acid.

– A new solutan echinoderm, Pahvanticystis utahensis gen. et sp. nov. is described from the upper part of the Weeks Formation (Guzhangian). The Cambrian (Series 3) succession of the central House Range in western Utah documents the early diversification of the class Soluta, which is characterized by a major ecological transition from sessile, 'pelmatozoan' primitive taxa (Colei-carpus, Wheeler Formation), to more and more vagile, temporarily attached (Castericystis, Marjum Formation), to mostly unattached, 'homalozoan' derived forms (Pahvanticystis, Weeks Formation). The morphology of Pahvanticystis is remarkably intermediate between those of Castericystis and Minervaecystis. Its twisted, flattened dististele possibly represents an adaptation for a more efficient crawling atop soft substrates. This morphological feature also questions the phylogenetic relationships between syringocrinid and dendrocystitid solutans, and the possible evolution of the latter from basal, Pahvanticystis-or Minervaecystis-like syringocrinids by paedomorphosis.

Presently more than 1900 species of sea stars are recognized, of which 77 are recorded for the coast of Brazil. Although the first starfish record in Brazil was published 363 years ago, our knowledge of this fauna remains unsatisfactory from a systematic and ecological point of view, particularly in the north and northeastern regions of the country. This study provides the first annotated list of sea stars from northeastern Brazil. Material described herein is housed at the collections of the Federal University of Paraíba, Federal University of Sergipe, and the Federal University of Bahia, Museum of Zoology of the University of São Paulo and Museu Nacional do Rio de Janeiro. Twenty-one species were identified, belonging to 12 genera, 10 families, and 5 orders. Descriptions of species are provided.  Three new occurrences were recorded for northeast Brazil: Astropecten alligator, Luidia ludwigi scotti, and Mithrodia clavigera. Highest diversities of Asteroidea were encountered for the states of Bahia (n = 14 spp), Paraíba (n = 12 spp) and Pernambuco (n = 9 spp). No species were recorded for the states of Maranhão and Sergipe. Sandy substrates and depths
below 10 m were the least sampled areas over the continental shelf. Herein we provide a first panorama on the fauna of Asteroidea occurring in the northeast region of Brazil, hopefully to function as a basic reference for biodiversity studies in this poorly studied area.

Knowledge of phylogenetic relationships among species is fundamental to understanding basic patterns in evolution and underpins nearly all research programs in biology and paleontology. However, most methods of phylogenetic inference typically used by paleontologists do not accommodate the idiosyncrasies of fossil data and therefore do not take full advantage of the information provided by the fossil record. The advent of Bayesian “tip-dating” approaches to phylogeny estimation is especially promising for paleo-systematists because time-stamped comparative data can be combined with probabilistic models tailored to accommodate the study of fossil taxa. Under a Bayesian framework, the recently developed fossilized birth‒death process (FBD) provides a more realistic tree prior model for paleontological data that accounts for macroevolutionary dynamics, preservation, and sampling when inferring phylogenetic trees containing fossils. In addition, FBD tree prior also allows for the possibility of sampling ancestral morphotaxa. Although paleontologists are increasingly embracing probabilistic phylogenetic methods, these recent developments have not previously been applied to the deep-time invertebrate fossil record. Here, I examine phylogenetic relationships among Ordovician through Devonian crinoids using a Bayesian tip-dating approach. Results support several clades recognized in previous analyses sampling only Ordovician taxa, but also reveal instances where phylogenetic affinities are more complex and extensive revisions are necessary, particularly among the Cladida. The name Porocrinoidea is proposed for a well-supported clade of Ordovician ‘cyathocrine’ cladids and hybocrinids. The Eucladida is proposed as a clade name for the sister group of the Flexibilia herein comprised of cladids variously considered ‘cyathocrines’, ‘dendrocrines’, and/or ‘poteriocrines’ by other authors.

El erizo de mar Toxopneustes roseus se encuentra ampliamente distribuido a lo largo de la costa este del Pacífico tropical, desde México hasta el norte de Perú. El presente estudio tiene como propósito evaluar rasgos poblacionales de esta especie, tales como patrón de distribución, densidad poblacional, crecimiento poblacional y mortalidad natural, así como la relación entre la densidad y algunas variables ambientales (hidrográficas y atmosféricas). Durante veinticuatro meses (octubre 2009 a septiembre 2011) se hicieron conteos utilizando transectos en banda en tres localidades de la costa de Oaxaca: Estacahuite, Dos Hermanas e Isla Cacaluta. Adicionalmente se registró la temperatura, salinidad y pH en las tres localidades de estudio. Los registros de irradiación y precipitación pluvial se obtuvieron de bases de datos. El patrón de distribución espacial se caracterizó utilizando el índice de Morisita y los modelos de probabilidad de Poisson y distribución Binomial Negativa. La densidad poblacional se estimó mediante el conteo de individuos por metro cuadrado. Para obtener los parámetros de crecimiento poblacional se utilizó el método de mínimos cuadrados y se realizó el ajuste mediante el algoritmo de mínima verosimilitud. La mortalidad natural se estimó mediante el método de Berry. Se aplicó un análisis de Regresión Lineal Múltiple para evaluar la relación entre la densidad y las variables hidrográficas y atmosféricas medidas. En las tres localidades de estudio el patrón de distribución de T. roseus fue agregado en la mayoría de los meses y la densidad promedio fue 0.12±0.02 ind•m-2 (Estacahuite), 0.05±0.01 ind•m-2 (Dos Hermanas) y 0.04±0.01 ind•m-2 (Isla Cacaluta). El valor estimado de los coeficientes para el crecimiento poblacional fueron: K= 75.697, No=3.376 y r= 0.263 (Estacahuite), K= 1108, No=7.742 y r= 0.271 (Dos Hermanas), y K= 3719.65, No=8.82 y r= 0.241 (Isla Cacaluta). En Estacahuite la mortalidad natural fue 0.54 y en Dos Hermanas 0.46. De las variables ambientales medidas, la precipitación pluvial tuvo una relación directa, pero no determinante con la densidad poblacional de T. roseus en Isla Cacaluta. Debido a las diferencias encontradas en las tres localidades de estudio, se puede inferir que los diversos factores que podrían determinar el crecimiento poblacional de T. roseus son: 1) áreas con mayor extensión en general, 2) disponibilidad de recursos y 3) el aporte de sedimento por la presencia de ríos en las localidades.

Of the major deuterostome groups, the echinoderms with their multiple forms and complex development are arguably the most mysterious. Although larval echinoderms are bilaterally symmetric, the adult body seems to abandon the larval body plan and to develop independently a new structure with different symmetries. The prevalent pentamer structure, the asymmetry of Loven's rule and the variable location of the periproct and madrepore present enormous difficulties in homologizing structures across the major clades, despite the excellent fossil record. This irregularity in body forms seems to place echinoderms outside the other deuterostomes. Here I propose that the predominant five-ray structure is derived from a hexamer structure that is grounded directly in the structure of the bilaterally symmetric larva. This hypothesis implies that the adult echinoderm body can be derived directly from the larval bilateral symmetry and thus firmly ranks even the adult echinoderms among the bilaterians. In order to test the hypothesis rigorously, a model is developed in which one ray is missing between rays IV-V (Loven's schema) or rays C-D (Carpenter's schema). The model is used to make predictions, which are tested and verified for the process of metamorphosis and for the morphology of recent and fossil forms. The theory provides fundamental insight into the M-plane and the Ubisch', Loven's and Carpenter's planes and generalizes them for all echinoderms. The theory also makes robust predictions about the evolution of the pentamer structure and its developmental basis. *** including corrections (see footnotes) ***

New examples of Bathonian (Middle Jurassic) parasitic exocysts on acrosaleniid echinoid tests are recorded from
northern France. These exocysts can be attributed to the life activity of copepod crustaceans and are considered
to have been formed as a result of copepod larval settlement in these echinoids by way of the gonopores. Sexual
dimorphism is recognised in copepod-infested Acrosalenia spinosa L. Agassiz, 1840, on the basis of size and
position of gonopores, those in females being larger and wider apart, those in males smaller and situated subcentrally.
The previous stratigraphic range of copepod cysts of this type (i.e., Middle Oxfordian to Middle Kimmeridgian)
can now be extended down to the base of the Bathonian (convergens Subzone).