Contributed carnivorous sponges: JV MK. Contributed Hexactinellida: MD. Contributed new developments: DE. Contributed distribution, maps: NS BV.
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Contributed carnivorous sponges: JV MK. Contributed Hexactinellida: MD. Contributed new developments: DE. Contributed distribution, maps: NS BV. Performed biodiversity analysis: NdV. Contributed regional and online resources, conclusions and perspectives: JH. With the completion of a single unified classification, the Systema Porifera SP and subsequent development of an online species database, the World Porifera Database WPD , we are now equipped to provide a first comprehensive picture of the global biodiversity of the Porifera.
An introductory overview of the four classes of the Porifera is followed by a description of the structure of our main source of data for this paper, the WPD. We also mapped for the first time the species richness of a comprehensive set of marine ecoregions of the world, data also extracted from the WPD. Perhaps not surprisingly, these distributions appear to show a strong bias towards collection and taxonomy efforts.
Only when species richness is accumulated into large marine realms does a pattern emerge that is also recognized in many other marine animal groups: high numbers in tropical regions, lesser numbers in the colder parts of the world oceans. Preliminary similarity analysis of a matrix of species and marine ecoregions extracted from the WPD failed to yield a consistent hierarchical pattern of ecoregions into marine provinces.
Global sponge diversity information is mostly generated in regional projects and resources: results obtained demonstrate that regional approaches to analytical biogeography are at present more likely to achieve insights into the biogeographic history of sponges than a global perspective, which appears currently too ambitious.
We also review information on invasive sponges that might well have some influence on distribution patterns of the future. Sponges, phylum Porifera, are the oldest metazoan group still extant on our planet.
Their continued survival in vast numbers in Recent seas and in freshwater habitats is closely linked to the apparent adaptability of their bauplan to dramatic changes in environmental characteristics and competing biota  , . Sponges Fig. Recent research also indicates an ability to take up dissolved organic matter . Sponges have a simple level of organization: there are specialized cells for a variety of life functions, but these are not organized into tissues or organs.
These chambers have a lining of flagella-bearing cells choanocytes, Fig. An exception to this is in the so-called carnivorous sponges, highly adapted deep-sea forms, in which the aquiferous system is non-existent, but which have a sticky outer surface with which small prey animals are captured .
The space Fig. SEM image of cross section of mesohyl of the demosponge Scopalina ruetzleri obtained by freeze-fracturing technique courtesy L. Detail of choanocyte chamber of Scopalina ruetzleri courtesy L. Sponges grow in distinct shapes Fig. The skeleton may also be supplemented by exogenous materials, such as sand grains. Depending on the nature and density of these building components, sponge species may variously be soft, compressible, fragile or rock hard in consistency.
Sponges come in various shapes and sizes, from flat cushions to elaborate branching or cup-shaped forms, from tiny crusts measured in mm, to giant shapes in meters. Sponges have numerous microscopic openings the incurrent pores and one or a few larger vents the excurrent oscules.
The shapes of sponges are variable among different species and genera, but also vary to some extent between individuals of the same species in response to environmental factors such as hydrodynamics, light and turbidity.
A great diversity of symbiotic organisms often thrive inside or on the body of a sponge, from microscopic prokaryotes, e. Knowledge of sponge biodiversity is still largely incomplete. To date, about 11, species have been formally described of which approximately 8, are considered valid see below , but as many as twice that number are thought to exist. Sponges are currently divided among four distinct classes, 25 orders, families and genera  ,  , but many of these higher taxa are under discussion due to new insights obtained from molecular systematic methods and new considerations of their morphological characteristics.
Fossil sponges comprise a similar additional diversity  There are several hundred freshwater species. Due to the limited swimming capabilities of most sponge larvae, and occasional asexual propagation, most sponges occur in regional or local areas of endemism, unless spread globally or regionally in an inadvertent manner by shipping traffic.
Sponges may be found vertically from the eulittoral zone to hadal depths, horizontally from the tropics to the highest latitudes, locally from epifaunal rocky communities to mud bottoms and ephemeral freshwater habitats.
Their importance for the global ecosystem is high but not widely appreciated  , . Sponges are efficient filter feeders, vital to the health and economics of all marine systems by linking the nutrients of the open water column with benthic communities.
Symbionts of sponges play a decisive role in the nitrogen cycle of many habitats and may contribute significantly to organic production in oligotrophic habitats. Specialized sponges are important bio-eroders in coral reefs, coralline bottoms and oyster beds and they may compete successfully with other sessile organisms such as corals.
Specific groups have an essential function in binding unconsolidated substrate such as coral rubble and pebbles into stable surfaces. Many fossil sponges and a small group of Recent sponges are capable of building extensive reef formations that today, in some locations, shape the contours of the benthos, and now form uplifted terrestrial habitats.
Megabenthic species may form high-density aggregations in many shelf edge and seamount regions playing a so far unexplored role in deep-sea ecosystems. These are only a few general features of the ecosystem services provided by the global sponge community  — . Although sponges have been known to mankind since the earliest civilizations YBP, see  they were not recognized as an independent metazoan lineage until well into the 19 th century, when Robert Grant  first observed their unique morphology and physiology and coined the name Porifera for them.
Since then, spongology, the study of all aspects of the biology, ecology, taxonomy and chemistry of sponges, has grown into a discipline attracting a steadily increasing population of hundreds of scientists worldwide, many of whom devote a lifetime career to the study of this group. Increasingly, sponges are studied as part of a broader enterprise attempting to detail the Tree of Life. Apart from nurturing academic interest, sponges play an important role in human health as producers of chemical compounds with useful pharmaceutical properties, including antitumor, anti-infective and anti-inflammatory properties .
Natural sponges are still harvested for personal, industrial, and artistic use. For the first time since the appearance of the consensus classification, we review here the global diversity of the Recent Porifera, giving a summary of the major groups and their currently established taxon richness.
We also make a first attempt to review distribution patterns of species and higher taxa over the global seas and oceans. Because of the review nature of this study, methods employed are diverse.
We summarize here the major methodological approaches, which are further explained in the various sections below. Taxonomic and distribution data were extracted from the online World Porifera Database  accessed Sept 30 , and supplemented with a survey of the literature on sponge diversity. Figures, tables and maps are partially the result of newly analyzed data.
The reduction in the number of provinces and ecoregions was determined empirically by repeated clustering attempts with different minimum record numbers in which level of resolution of the dendrogram was observed. This reduction is justified by the lack of sufficient exploration of these geographic units, but precise levels minimum of 50 and 20 records were chosen arbitrarily.
Author contributions outlined below were solicited on the basis of expert knowledge and skills. Demospongiae is the largest and most diverse class of the Porifera. It unites  sponges with siliceous spicules Fig.
Like in Hexactinellida see below siliceous spicules are divided into megascleres, which strengthen the framework of the sponges, and microscleres, which have various — possibly defensive, possibly supportive of soft tissues, but generally unclear — functions. Microscleres are frequently more common in the outer regions of the sponges and often surround aquiferous canals.
Members of the class Homoscleromorpha also possess tetraxonic siliceous spicules, but they lack a subdivision in mega- and microscleres. Occasionally the skeleton is absent, a feature shared again with some Homoscleromorpha. Rare forms with limestone basal skeletons are living links to Paleozoic reef-building sponges. Larvae are usually of the parenchymella type solid with overall ciliation , but in some groups hollow larvae occur  , .
The most recent summary of the Porifera classification  recognized 15 ordinal groups, one of which was recently transferred to the class Homoscleromorpha see below. Freshwater sponges have so far been included in the latter order, but are probably unrelated see below. The integrity of these groups is currently being investigated using molecular techniques and proposals to rearrange all ordinal groups and their families is imminent  ; see also below. Bath sponge, Spongia officinalis , Greece photo courtesy E.
Voultsiadou ; B. Bathyal mud sponge Thenea schmidti ; C. Papillae of excavating sponge Cliona celata protruding from limestone substratum photo M. Giant rock sponge, Neophrissospongia , Azores photo F. Roozendaal ; F. Amphimedon queenslandica photo of holotype in aquarium, photo S. Walker ; G. SEM images of a selection of microscleres and megascleres, not to scale, sizes vary between 0. Demosponges demonstrate a tremendous diversity that can only be illustrated with a few iconic examples: The well-known bath sponges family Spongiidae, Fig.
They grow in warmer waters worldwide and have been exploited to near-extinction in many areas. Nowadays, use of bath sponges is limited to specialized industries and as a curiosity for tourists . Deep-sea species of the genus Thenea Astrophorida, Fig. Excavating or boring sponges Fig. They belong to families Clionaidae order Hadromerida , Thoosidae order Astrophorida and genus Aka family Phloeodictyidae. Many living species are found in deeper waters of tropical and warm- temperate regions and are thought to be isolated survivors of a much larger fossil sponge fauna, e.
A counterpart species in the Indo-Pacific X. The Australian haplosclerid Amphimedon queenslandica Fig. It proved beyond reasonable doubt that sponges are at the very base of the Metazoan Tree of Life. Some sponges of the order Poecilosclerida, class Demospongiae, have a surprising carnivorous feeding regime  ,  ,  , instead of being filter-feeders, as is typical of sponges.
These typically deep-sea sponges lack the aquiferous system and the choanocyte cells which are considered to be diagnostic for Porifera .
An aquiferous system is maintained only in the genus Chondrocladia , in which, however, it is apparently not used for water filtration but for the inflation of turgescent spheres lined by the same sticky cover of hook-like spicules. They prey on a variety of small invertebrates, mostly crustaceans, with setae or bristles that ensnare on the spicule cover.
In the absence of any gut or digestive cavity, digestion is performed by cells migrating toward the prey and acting individually to phagocytize and digest its fragments intracellularly . This system is unique in the Metazoa, but it parallels the behaviour of individual sponge cells, which perform the various functions of differentiated tissue, organs and a nervous system, which sponges lack.
By the end of the twentieth century, 90 carnivorous sponges were classified in the family Cladorhizidae, within three genera, Cladorhiza , Asbestopluma and Chondrocladia. They were all found in the deep sea, including the depth record for sponges, with a species known from m. Increased interest in these sponges, due to the discovery that they are carnivorous, and due to the development of manned submersibles and ROVs, has shown that this diversity was largely underestimated.
To date, species are known, classified in three families and eight genera, and several new species and a new genus are in the course of description.
Komposisi Jenis Dan Kepadatan Sponge (Porifera: Demospongiae) Di Kepulauan Spermonde Kota Makassar
DOI Download full text Bahasa Indonesia, 7 pages. Haris, Abdul, et al. Sponge is one of the components on the coastal and marine ecosystems, especially coral reefs and seagrass beds.
Global Diversity of Sponges (Porifera)