''Phyllodesmium poindimiei'' (AKA: Spun Of Light) is an
Alcyonacea
Alcyonacea, or soft corals, are an order of corals. In addition to the fleshy soft corals, the order Alcyonacea now contains all species previously known as "gorgonian corals", that produce a more or less hard skeleton, though quite different f ...
feeding, aeolid
nudibranch
Nudibranchs () are a group of soft-bodied marine gastropod molluscs which shed their shells after their larval stage. They are noted for their often extraordinary colours and striking forms, and they have been given colourful nicknames to mat ...
Gastropod belonging to the family
Facelinidae
The Facelinidae are a taxonomic family of colorful sea slugs. These are specifically aeolid nudibranchs. They are marine gastropod molluscs.Bouchet, P. (2012). Facelinidae. Accessed through: World Register of Marine Species at http://www.marinesp ...
.
Cerata
:''The tortrix moth genus ''Cerata'' is considered a junior synonym of ''Cydia.
Cerata, singular ceras, are anatomical structures found externally in nudibranch sea slugs, especially in aeolid nudibranchs, marine opisthobranch gastropod mollus ...
are important in this clade in terms of their physical defense and efficient metabolic processes. This species is spread sporadically along tropical coastal regions such as Australia, Hawaii, and the
Indo-Pacific
The Indo-Pacific is a vast biogeographic region of Earth.
In a narrow sense, sometimes known as the Indo-West Pacific or Indo-Pacific Asia, it comprises the tropical waters of the Indian Ocean, the western and central Pacific Ocean, and the ...
living in diverse marine habitats such as coral reefs.
Unlike other species in the
''Opisthobranch'' Mollusca clade, ''P. poindimiei''’s lush pink cerata are used for defensive purposes other than
Nematocyst (dinoflagellate)
A nematocyst is a subcellular structure or organelle containing extrusive filaments found in two families of athecate dinoflagellates (a group of unicellular eukaryotes), the Warnowiaceae and Polykrikaceae. It is distinct from the similar subce ...
capture and toxin release. Organismal ties within these thriving, tropical ecosystems can be determinants of environment change, which affects massive coral ecosystems.
Continuously changing marine ecosystems, such as
coral reef
A coral reef is an underwater ecosystem characterized by reef-building corals. Reefs are formed of colonies of coral polyps held together by calcium carbonate. Most coral reefs are built from stony corals, whose polyps cluster in groups.
C ...
s, are directly linked to the evolution of organisms that live and thrive in the tropics such as the soft nudibrach ''P. poindimiei''.
Evolution and description
This
monophyletic
In cladistics for a group of organisms, monophyly is the condition of being a clade—that is, a group of taxa composed only of a common ancestor (or more precisely an ancestral population) and all of its lineal descendants. Monophyletic ...
clade of mollusks were
prosobranchs that eventually rid themselves of an exoskeleton.
Elongated metazoans will lengthen themselves out to about 50 mm at longest. ''P. poindimiei'' typically has two pairs of tentacles with a built in
olfactory
The sense of smell, or olfaction, is the special sense through which smells (or odors) are perceived. The sense of smell has many functions, including detecting desirable foods, hazards, and pheromones, and plays a role in taste.
In humans, i ...
system containing an eye at each base. The soft shell-less slug has cerata outgrowths on its upper side filled with the organism’s respiratory and digestive systems and can be cast off for protective purposes.
These cylindrical gill cavities typically have two main defenses resulting from nematocyst or
zooxanthellae
Zooxanthellae is a colloquial term for single-celled dinoflagellates that are able to live in symbiosis with diverse marine invertebrates including demosponges, corals, jellyfish, and nudibranchs. Most known zooxanthellae are in the genus '' ...
obtainment.
These translucent cerata for most ''Phyllodesmium'' contain
cnidosac
A cnidosac is an anatomical feature that is found in the group of sea slugs known as aeolid nudibranchs, a clade of marine opisthobranch gastropod molluscs. A cnidosac contains cnidocytes, stinging cells that are also known as cnidoblasts or nema ...
s at the tips in which nudibranchs digest nematocysts from
Cnidaria
Cnidaria () is a phylum under kingdom Animalia containing over 11,000 species of aquatic animals found both in Fresh water, freshwater and Marine habitats, marine environments, predominantly the latter.
Their distinguishing feature is cnidocyt ...
n prey, such as jellyfish or corals. ''P. poindimiei'' lack these cnidosacs that could be used for its own defense against the swimming crab
Thalamita integer.
Another modification this species lacks is the ability to accumulate zooxanthellae, microscopic photosynthetic dinoflagellates, in the branched digestive tract.
The non-symbiotic species such as ''P. poindimiei'' were thought to have evolved earlier than the symbiotic clades.
Diet and growth
''P. poindimiei'' live up to twelve months and develop from an egg to a free-swimming
veliger larva. They feed on Telesto, Caridoa, and other Alcyonaceans with very small radula.
Members of the Porifera phyla, sponges, act as
epibiont
An epibiont (from the Ancient Greek meaning "living on top of") is an organism that lives on the surface of another living organism, called the basibiont ("living underneath"). The interaction between the two organisms is called epibiosis. An epi ...
on sediment or ectozoans on organisms, such as ''
Octocorallia
Octocorallia (also known as Alcyonaria) is a class of Anthozoa comprising around 3,000 species of water-based organisms formed of colonial polyps with 8-fold symmetry. It includes the blue coral, soft corals, sea pens, and gorgonians (sea fan ...
''. Excess spongiform growth thereby prevents this Aeolid from consuming octocoral, a common prey for ''P. poindimiei'' which can become a problem for these picky eaters.
Ecology and conservation
Heterobranchs range from aquatic to terrestrial environments but ''P. poindimiei'' specifically tends to surround itself with other multicellular organisms in tropical
sessile
Sessility, or sessile, may refer to:
* Sessility (motility), organisms which are not able to move about
* Sessility (botany), flowers or leaves that grow directly from the stem or peduncle of a plant
* Sessility (medicine), tumors and polyps that ...
environments such as diverse coral reefs. Many of the tropical locations where ''P. poindimiei'' reside are climate change research
biotopes.
Environment change is ideally studied using these animals because of their prompt life span and revival linkage to a diverse habitat sensitive to oceanic temperature change that could potentially cause
coral bleaching
Coral bleaching is the process when corals become white due to various stressors, such as changes in temperature, light, or nutrients. Bleaching occurs when coral polyps expel the zooxanthellae (dinoflagellates that are commonly referred to as al ...
.
Most species of ''Phyllodesmium'' are found along the coastline of Australia, Hawaii, and the Indo-Pacific regions.
Coastal channels and
estuaries
An estuary is a partially enclosed coastal body of brackish water with one or more rivers or streams flowing into it, and with a free connection to the open sea. Estuaries form a transition zone between river environments and maritime environme ...
allow for ample shelter for these marine gastropod nudibranchs.
References
External links
*
{{Taxonbar, from=Q7188810
Facelinidae
Gastropods described in 1928