Cribricyatha is an extinct

class Class, Classes, or The Class may refer to: Common uses not otherwise categorized * Class (biology), a taxonomic rank * Class (knowledge representation), a collection of individuals or objects * Class (philosophy), an analytical concept used d ...

sponge Sponges or sea sponges are primarily marine invertebrates of the animal phylum Porifera (; meaning 'pore bearer'), a basal clade and a sister taxon of the diploblasts. They are sessile filter feeders that are bound to the seabed, and a ...

-like animals which lived in the early to mid-

Cambrian Period The Cambrian ( ) is the first geological period of the Paleozoic Era, and the Phanerozoic Eon. The Cambrian lasted 51.95 million years from the end of the preceding Ediacaran period 538.8 Ma (million years ago) to the beginning of the Ordovici ...

( Tommotian to

Botomian Cambrian Stage 4 is the still unnamed fourth stage of the Cambrian and the upper stage of Cambrian Series 2. It follows Cambrian Stage 3 and lies below the Wuliuan. The lower boundary has not been formally defined by the International Commission ...

Description

Cribricyatha were cup-shaped filter feeders similar to archaeocyathan sponges, with a skeleton composed of

magnesium Magnesium is a chemical element; it has Symbol (chemistry), symbol Mg and atomic number 12. It is a shiny gray metal having a low density, low melting point and high chemical reactivity. Like the other alkaline earth metals (group 2 ...

-rich

calcite Calcite is a Carbonate minerals, carbonate mineral and the most stable Polymorphism (materials science), polymorph of calcium carbonate (CaCO3). It is a very common mineral, particularly as a component of limestone. Calcite defines hardness 3 on ...

microgranules. The base is narrow, broadening upwards into a solid conical or semi-conical shell. In horizontal cross-section, the cup may be circular, elliptical, cardioid (heart-shaped), or quadrate (square-shaped).''Treatise on Invertebrate Paleontology'' Part E, Revised. Porifera, Volumes 4 & 5: Hypercalcified Porifera, Paleozoic Stromatoporoidea & Archaeocyatha, liii + 1223 p., 665 figs., 2015, availabl
here
. All cribricyaths can be characterized by a series of peripterates, ribbon-like crests ringing around the outer surface of the shell. In cribricyaths of the

order Order, ORDER or Orders may refer to: * A socio-political or established or existing order, e.g. World order, Ancien Regime, Pax Britannica * Categorization, the process in which ideas and objects are recognized, differentiated, and understood ...

Cribricyathida, the peripterates may be supplemented by baculi, low ridges running parallel to the main shaft of the shell. Internally, the shell is hollow. Members of the superfamilies Pyxidocyathoidea and Akademiophylloidea have a smaller enclosed layer nested within the shell: the inner wall. When present, the inner wall is fused on one edge to the inner surface of the outer wall. The inner wall is porous and may have its own series of looping crests, known as striae. The cup develops from the outside-in, with the inner wall deposited after the outer wall.

Ecology

Cribricyaths coexisted for some time with their archeocyathan relatives, but they were generally much smaller, with a maximum height of only 2 cm (0.8 inches) and a maximum diameter of only 2 mm. They were probably reef cryptobionts, meaning that they inhabited sheltered areas (such as the small crevices under or between rocks and reef-building organisms). Cribricyaths were

endemic Endemism is the state of a species being found only in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also foun ...

to a marine region equivalent to modern

North Asia North Asia or Northern Asia () is the northern region of Asia, which is defined in geography, geographical terms and consists of three federal districts of Russia: Ural Federal District, Ural, Siberian Federal District, Siberian, and the Far E ...

and

Mongolia Mongolia is a landlocked country in East Asia, bordered by Russia to the north and China to the south and southeast. It covers an area of , with a population of 3.5 million, making it the world's List of countries and dependencies by po ...

. Cribricyaths were usually subordinate to archaeocyathans as reef-building organisms, though they managed to be diverse or voluminous contributors for a few reef systems.

Taxonomy

From the ''

Treatise on Invertebrate Paleontology The ''Treatise on Invertebrate Paleontology,'' published from 1953–2007 by the Geological Society of America and the University of Kansas, then 2009–present by the University of Kansas Paleontological Institute, is a definitive multi-authore ...

'' (Part E revised, Volumes 4–5, 2015): * Class Cribricyatha Vologdin, 1961 ** Order Cribricyathida Vologdin, 1961 *** Superfamily Conoidocyathoidea Vologdin, 1964 **** Family Conoidocyathidae Vologdin, 1964 ***** '' Conoidocyathus'' Vologdin, 1964 tdabanian 1 – Botomian 3*** Superfamily Pyxidocyathoidea Vologdin, 1964 **** Family Pyxidocyathidae Vologdin, 1964 ***** '' Dolichocyathus'' Vologdin, 1964 otomian 1 – 3***** '' Lucyathus'' Vologdin, 1957 tdabanian 1 – Botomian 3***** '' Szecyathus'' Vologdin, 1957 tdabanian 2 – Botomian 3** Order Vologdinophyllida Radugin, 1964 *** Superfamily Vologdinophylloidea Radugin, 1964 **** Family Leibaellidae Jankauskas, 1965 ***** '' Dubius'' Jankauskas, 1969 ommotian 3 – Botomian 1***** '' Leibaella'' Jankauskas, 1964 ommotian 4 – Atdabanian 3***** '' Ramifer'' Jankauskas, 1969 ommotian 2 – Atdabanian 4**** Family Vologdinophyllidae Radugin, 1964 ***** '' Manaella'' Jankauskas, 1964 tdabanian 1***** '' Vologdinophyllum'' Radugin, 1962 tdabanian 1*** Superfamily Akademiophylloidea Radugin, 1964 **** Family Akademiophyllidae Radugin, 1964 ***** '' Akademiophyllum'' Radugin, 1964 tdabanian 1 – Botomian 1 ***** '' Eriphyllum'' Radugin, 1966 tdabanian 1**** Family Striatocyathidae Vologdin & Jankauskas, 1968 ***** '' Achorocyathus'' Jankauskas, 1969 tdabanian 1 – 3***** '' Rarocyathus'' Vologdin & Jankauskas, 1968 tdabanian 3 – Botomian 1***** '' Striatocyathus'' Vologdin & Jankauskas, 1968 tdabanian 1 – Botomian 1

References

{{Taxonbar, from=Q118136520 Cambrian sponges Cambrian animals Prehistoric animal classes