''Aplysina cavernicola'' is a species of

sponge Sponges, the members of the phylum Porifera (; meaning 'pore bearer'), are a basal animal clade as a sister of the diploblasts. They are multicellular organisms that have bodies full of pores and channels allowing water to circulate through t ...

in the family

Aplysinidae Aplysinidae is a family of sea sponges in the order Verongiida. Its growths are either shaped like a fan or a club. Contained within the family are three recognized genera and six unrecognized ones. It was first authenticated and described by ...

. It is native to the

Mediterranean Sea The Mediterranean Sea is a sea connected to the Atlantic Ocean, surrounded by the Mediterranean Basin and almost completely enclosed by land: on the north by Western and Southern Europe and Anatolia, on the south by North Africa, and on the ea ...

where it grows in caves and under overhangs.

Description

''Aplysina cavernicola'' forms clumps that may be up to across. It has a base that adheres to a rock or other hard surface, out of which project a number of finger-like processes up to long and in diameter. The surface is sparsely covered with small conical protrusions, which are caused by the tips of horny fibres embedded in the tissues. There are no

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 ( ...

, structural support being provided by a mesh of spongin fibres. Water is drawn in through pores known as

ostia Ostia may refer to: Places *Ostia (Rome), a municipio (also called ''Ostia Lido'' or ''Lido di Ostia'') of Rome *Ostia Antica, a township and port of ancient Rome *Ostia Antica (district), a district of the commune of Rome Arts and entertainment ...

at the base of the sponge and ejected from the oscuili which are situated in slight depressions at the tips of the processes. The body colour is yellowish.

Ecology

This sponge is a

hermaphrodite 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 Taxonomy (biology), taxonomic groups of animals (mostly invertebrate ...

; ciliated larvae known as

parenchymella Parenchymella is a type of larva of a 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). T ...

larvae are released into the water and soon settle in a suitable location and undergo

metamorphosis Metamorphosis is a biological process by which an animal physically develops including birth or hatching, involving a conspicuous and relatively abrupt change in the animal's body structure through cell growth and differentiation. Some inse ...

into juvenile sponges. This sponge accumulates brominated

isoxazoline Isoxazolines are a class of five-membered heterocyclic chemical compounds, containing one atom each of oxygen and nitrogen which are located adjacent to one another. The ring was named in-line with the Hantzsch–Widman nomenclature. They are stru ...

alkaloid Alkaloids are a class of basic, naturally occurring organic compounds that contain at least one nitrogen atom. This group also includes some related compounds with neutral and even weakly acidic properties. Some synthetic compounds of similar ...

s in its tissues at concentrations of up to 10% of its dry body weight. By incorporating these biologically active compounds into experimental diets, it has been shown in feeding trials that they are distasteful to the

sphinx blenny The sphinx blenny (''Aidablennius sphynx'') is a species of combtooth blenny, and the only species in the genus ''Aidablennius''. It was described by Achille Valenciennes in 1836, originally under the genus '' Blennius'',Cuvier, G. and A. Valenci ...

(''Blennius sphinx''), a

polyphagous Feeding is the process by which organisms, typically animals, obtain food. Terminology often uses either the suffixes -vore, -vory, or -vorous from Latin ''vorare'', meaning "to devour", or -phage, -phagy, or -phagous from Greek φαγε ...

Mediterranean fish, while other sponges are readily eaten. Certain metabolic derivatives of these isoxazolines, such as dienone and aeroplysinin, are not distasteful to the fish, but may have anti-microbial properties that protect the sponge from

bacteria Bacteria (; singular: bacterium) are ubiquitous, mostly free-living organisms often consisting of one biological cell. They constitute a large domain of prokaryotic microorganisms. Typically a few micrometres in length, bacteria were among ...

pathogen In biology, a pathogen ( el, πάθος, "suffering", "passion" and , "producer of") in the oldest and broadest sense, is any organism or agent that can produce disease. A pathogen may also be referred to as an infectious agent, or simply a germ ...

s. This sponge also bioaccumulates

radionuclide A radionuclide (radioactive nuclide, radioisotope or radioactive isotope) is a nuclide that has excess nuclear energy, making it unstable. This excess energy can be used in one of three ways: emitted from the nucleus as gamma radiation; transfer ...

s, and has been used as a

model organism A model organism (often shortened to model) is a non-human species that is extensively studied to understand particular biological phenomena, with the expectation that discoveries made in the model organism will provide insight into the workin ...

to study the presence of isotopes such as americium-241 in seawater.

References

{{Taxonbar, from=Q1891651 Animals described in 1959 Verongimorpha Fauna of the Mediterranean Sea