Minchinellidae is a family of
calcareous sponges, members of the class
Calcarea. It is the only family in the
monotypic
In biology, a monotypic taxon is a taxonomic group (taxon) that contains only one immediately subordinate taxon. A monotypic species is one that does not include subspecies or smaller, infraspecific taxa. In the case of genera, the term "unisp ...
order Lithonida. The families
Petrobionidae (genus ''
Petrobiona'')
and
Lepidoleuconidae (genus ''
Lepidoleucon'')
[''Treatise on Invertebrate Paleontology'' Part E, Revised. Porifera, Volume 3: Classes Demospongea, Hexactinellida, Heteractinida & Calcarea, xxxi + 872 p., 506 fig., 1 table, 2004, availabl]
here
. have also sometimes been placed within Lithonida, though more recently they have been moved to the order
Baerida.
[''Treatise on Invertebrate Paleontology'' Part E, Revised. Porifera, Volumes 4 & 5: Hypercalcified Porifera, Paleozoic Stromatoporoidea & Archaeocyatha, liii + 1223 p., 665 figs., 2015, availabl]
here
. Thanks to their hypercalcified structure, minchinellids have a fossil record reaching as far back as the
Jurassic Period
The Jurassic ( ) is a geologic period and stratigraphic system that spanned from the end of the Triassic Period million years ago (Mya) to the beginning of the Cretaceous Period, approximately 143.1 Mya. The Jurassic constitutes the second and m ...
.
Description
Minchinellids are hypercalcified sponges. They have a robust skeleton of tetractine (four-rayed) calcareous
spicules. The tetractine spicules are
propeller
A propeller (often called a screw if on a ship or an airscrew if on an aircraft) is a device with a rotating hub and radiating blades that are set at a pitch to form a helical spiral which, when rotated, exerts linear thrust upon a working flu ...
-shaped, with three curved actines (rays) radiating perpendicular to a straight basal actine. These spicules may be linked by their basal actines or cemented together by calcite. The skeleton is reinforced with layers of loose diapason (
tuning fork
A tuning fork is an acoustic resonator in the form of a two-pronged fork with the prongs ( ''tines'') formed from a U-shaped bar of elastic metal (usually steel). It resonates at a specific constant pitch when set vibrating by striking it ag ...
-shaped) spicules. Minchinellid sponges have a
leuconoid
Sponges or sea sponges are primarily marine invertebrates of the animal phylum Porifera (; meaning 'pore bearer'), a Basal (phylogenetics) , basal clade and a sister taxon of the Eumetazoa , diploblasts. They are sessility (motility) , sessile ...
canal system.
List of genera
* †''
Bactronella''
Hinde, 1884 urassic–Miocene, Holocene?ref name=":0" />
* ''
Minchinella''
Kirkpatrick, 1908 olocene* ''
Monoplectroninia''
Pouliquen & Vacelet, 1970 olocene* †''
Muellerithalmia''
Reitner, 1987 pper Jurassicref name=":0" />
* ''
Petrostroma
''Petrostroma'' is a genus of calcareous sponges belonging to the family Minchinellidae.
Fossil species of this genus are found in Europe, but the extant type species, ''P. schulzei'', is found in Sagami Bay, Japan
Japan is an island co ...
''
Döderlein, 1892 retaceous–Holocene* ''
Plectroninia''
Hinde, 1900 urassic?, Cretaceous–Holocene* †''
Porosphaera''
Steinmann, 1878 retaceousref name=":0" />
* †''
Porosphaerella''
Welter, 1911 retaceousref name=":0" />
* †''
Retispinopora''
Brydone, 1912 retaceous–Paleoceneref name=":0" />
* †''
Sagittularia''
Welter, 1911 retaceousref name=":0" />
* ''
Tulearinia''
Vacelet, 1977 olocene
References
External links
* http://www.catalogueoflife.org/col/browse/tree
Calcaronea
Taxa named by Arthur Dendy
Sponge families
{{calcarea-stub