''Monanchora arbuscula'' is a species of marine

demosponge Demosponges (Demospongiae) are the most diverse class in the phylum Porifera. They include 76.2% of all species of sponges with nearly 8,800 species worldwide (World Porifera Database). They are sponges with a soft body that covers a har ...

in the family Crambeidae.

Description

Monanchora_arbuscula_(Red_encrusting_sponge)

''Monanchora arbusula'' is an encrusting or bushy demosponge which is dark red or bright scarlet on its inside and its surface. It forms either a low or tall mass, and individual organisms can have a bush, round, or fan shape. Its has scattered openings ( oscula) which are surrounded by a white collar in a star-like pattern. These collars are formed from exhalant canals which can sometimes not be seen. There are a few oscula which are on the ends of short tube-shaped lobes, and there are many knobs (

lamellae Lamella (plural lamellae) means a small plate or flake in Latin, and in English may refer to: Biology * Lamella (mycology), a papery rib beneath a mushroom cap * Lamella (botany) * Lamella (surface anatomy), a plate-like structure in an animal * ...

) along the surface. Often, specimens will have different combinations of kinds of

spicules Spicules are any of various small needle-like anatomical structures occurring in organisms Spicule may also refer to: *Spicule (sponge), small skeletal elements of sea sponges *Spicule (nematode), reproductive structures found in male nematodes ( ...

which attach them to their medium. When certain specimens lack one or more of these types of spicule, identifying them becomes problematic. For example, while encrusting specimens have fine filaments of roughly tylostyle spicules, bushy specimens have a central mesh of spicules which are surrounded by

spongin Spongin, a modified type of collagen protein, forms the fibrous skeleton of most organisms among the phylum Porifera, the sponges. It is secreted by sponge cells known as spongocytes. Spongin gives a sponge its flexibility. True spongin is found ...

. When taken out of the water, the exhalant canals collapse, and their red-orange interior color disappears. When handled, it will stain

human skin The human skin is the outer covering of the body and is the largest organ of the integumentary system. The skin has up to seven layers of ectodermal tissue guarding muscles, bones, ligaments and internal organs. Human skin is similar to most ...

because of the soft consistency of its tissue. The interior skeleton, however, is very tough.

Taxonomy

At the time of its description, the

basionym In the scientific name of organisms, basionym or basyonym means the original name on which a new name is based; the author citation of the new name should include the authors of the basionym in parentheses. The term "basionym" is used in both botan ...

''Pandaros'' ''arbusculum'' Duchassaing & Michelotti, 1864 was first used to name the species. It has also been described under the erroneous synonyms ''Monanchora barbadensis'' Hechtel, 1969 and ''M. unguifera'' de Laubenfels, 1953.

Distribution and habitat

Monanchora_barbadensis_(Red_Encrusting_Sponge)

''Monanchora arbuscula'' is found in

brackish Brackish water, sometimes termed brack water, is water occurring in a natural environment that has more salinity than freshwater, but not as much as seawater. It may result from mixing seawater (salt water) and fresh water together, as in estuari ...

waters and is associated with

reefs A reef is a ridge or shoal of rock, coral or similar relatively stable material, lying beneath the surface of a natural body of water. Many reefs result from natural, abiotic processes— deposition of sand, wave erosion planing down rock out ...

. It is found at depths of in tropical environments of the Western Atlantic. It may encrust different species in shallow reefs, such as dead

corals Corals are marine invertebrates within the class (biology), class Anthozoa of the phylum Cnidaria. They typically form compact Colony (biology), colonies of many identical individual polyp (zoology), polyps. Coral species include the important C ...

mollusc shells The mollusc (or molluskOften spelled mollusk shell in the USA; the spelling "mollusc" are preferred by ) shell is typically a calcareous exoskeleton which encloses, supports and protects the soft parts of an animal in the phylum Mollusca, which ...

, and gorgonian axes. It can also be found on hard substrate on the bottom, or in

mangrove A mangrove is a shrub or tree that grows in coastal saline water, saline or brackish water. The term is also used for tropical coastal vegetation consisting of such species. Mangroves are taxonomically diverse, as a result of convergent evoluti ...

ponds.

Behavior

As a species of demosponge, ''Monanchora arbuscula'' is

hermaphroditic In reproductive biology, a hermaphrodite () is an organism that has both kinds of reproductive organs and can produce both gametes associated with male and female sexes. Many taxonomic groups of animals (mostly invertebrates) do not have separ ...

. It begins its life cycle as a

zygote A zygote (, ) is a eukaryotic cell formed by a fertilization event between two gametes. The zygote's genome is a combination of the DNA in each gamete, and contains all of the genetic information of a new individual organism. In multicellula ...

, which develops into a free-swimming

larva A larva (; plural larvae ) is a distinct juvenile form many animals undergo before metamorphosis into adults. Animals with indirect development such as insects, amphibians, or cnidarians typically have a larval phase of their life cycle. The ...

. The larva lands on substrate and begins growing into a juvenile sponge there.

References

Poecilosclerida {{Improve categories, date=April 2022