Exam #3 Flashcards
Anthozoan Characteristics
-solitary or colonial
-medusa stage is completely absent
-contains over 6,000 species
-all are marine
-sexual reproduction by fertilization
-asexual reproduction by transverse or longitudinal fission or by pedal laceration
-ciliated groove (1 or 2) called a siphonoglyph(circulation of water through the gv)
How do Anthozoans differ from Hydrozoans polyps?
-differs from Hydrozoans polyps because the mouth extends to a pharynx and then extends into mesenteries
Mesentries contain…
nematocysts ( in
hydrozoan polyps, there are no nematocysts in
the gvc)
General Characteristic of Subclass Zoantharia (Hexacorallia)
number of polyps are six or multiples of six
General Characteristics of Subclass Alcyonaria (Octocorallia)
-known as soft corals
-eight polyps, complete mesenteries, and 8 primary septa
-majority have no CaCO3
-body integrity is usually maintained by spicules or sclerites
-low wave action
-more dominant in high sediment areas
-more calcite production
Order Stolonifera Characteristics
-known as mat polyps
-possess tall or short retractible polyps connected by stolons
-the combined stolons form a network or solid mat
-mesentry is poorly developed
-some are able to actively feed
-five families
-diverse
-tubes resemble those of feather duster worms
-polyp have small sclerites for support
-depend on the uptake of DOM for nutrition
Family Clavularia
multiple polyps connected by stolons
Clavularia sp.
clove polyps
Calyx
polyp can retract into this
Stolon
rootlike runners from the polyps of certain soft corals that aid in substrate adhesion, asexual reproduction and inter-colonial communication
Family Tubiporidae Characteristics
-Belongs to order stolonifera
-has a well known dark red calcium skeleton that looks like an organpipe
-calcium carbonate crystal is calcite which are fused sclerites instead of being imbedded for stability
-hermatypic
Stolon plates
Green star polyps
-Stoloniferians
-Pachyclavularia violacea
Subclass Alcyonaria
Order Telestacea
Order Telestacea Characteristics
-Telesto, Carijoa - snowflake corals
-polyps bud side polyp branches
-polyps are small, cylindrical, very tall
-polyps connect at base and grow from a creeping stolon
-spicules may fuse to give rigidity
-can often be identified by color of calcium carbonate, depth and location
-found in areas of high turbidity
-considered a fouling organism
-azooxanthellate and eat DOM
Telesto riisei
often covered with encrusting thing like sponges
Subclass Zoantharia
-Order Zoanthidae
-Order Actinaria
-Order Scleractinia
-Order Corallimorpharia
-Order Ceriantharia
-Order Antipatharia
Subclass Alcyonaria
-Order Stolonifera
-Order Telestacea
-Order Gorgonacea
-Order Alcyonacea
-Order Coenthecalia
-Order Pennatulacea
Order Pennatulacea
Sea pens
Renilla
-primary polyp (base)
-secondary polyps or autozoids
-rachis
Order Pennatulacea Characteristics
-a colonial anthozoan with polyp dimorphism
-a central calcium carbonate rod
-largest is 2 meters
-bioluminscent
-can relocate
-14 families
Order Coenthecalia (Helioporacea) Characteristics
-Two families: each has one genus and one has only one species
-One of two Alcyonarians that are hermatypic
-Dominated in the Tethys sea (warm water) but isnt fairing well now probably (maybe in the future?)
-Inside has veins of a blue pigment that is actually biliverdin which it makes by taking iron from the water
The two Alcyonarians that are hermatypic…
stoloniferans, and coenthecalia
Order Gorgonacea
- includes whip corals, sea feathers, sea fans, and the precious red corals
- commonly tropical or subtropical
- have been proposed for hormone derivatives for the production of birth control, anti-inflammatory, anti-tumor properties
- highly represented in the caribbean
- the coenenchyme contains fused sclerites
- most are zooxanthellate
- feed on POM
- harbor symbiotic organisms
Suborder Holaxonia contains a central axial rod of … that is layered with…
gorgonin (proteins plus mucopolysaccharides), coenenchyme
Gorgoninians require a small surface area for … and large surface area for … ; therefore most are branching often in one plane with the broadest side perpendicular to the water current; branches may be connected by crossbars
attachment, feeding
Thinner, spindly-stiff gorgonians are found …, flexible branched gorgonians are found in …, intermediate stiffness in …
deeper, moderate surge, shallow waters
Gorgonians reproduction is sexual or asexual by …; Junceella sp. exhibts branchlet dropping
fragmentation
Corallum rubrum - red coral
- Red corals are found in the western Mediterranean and in the Adriatic, most often found in holes and crevices at depths up to 300 ft.
- In red coral, gorgonin is replaced by fused red spicules
Gorgonian Colony Forms
encrusting, unbranched, candelabra, branched, bushy, whip-like, reticulate, pinnate
Order Alcyonacea
- 31 families in order
- known as soft corals
- they resemble scleratinian corals with the rubbery coenenchyme acting as a substrate for the colony instead of the calcareous skeleton
- skeleton fused calcareous spicules embedded in coenenchyme
- largely tropical
- colony can be massive mushroom shape or encrusting form
- some are zooxanthellate but some such as Dendronephthya sp. lack zooxanthellate thus making their spicules obvious
Spicule
a small skeletal inclusion or calcium body that aids in supporting the body structure of soft corals; also called sclerite; aids in taxonomic distinction
Corallite
the skeleton secreted by a indivudual polyp; the basic unit of a stony coral
Corallum
the entire skeleton of a coral secreted by an entire colony
Calyx (calice)
the opening of a corallite or the rim of the cuplike structure; raised area into which the polyp may be withdrawn
Theca
the skeletal wall around the polyp
Coenosteum
skeleton between the polyps
Septa
vertical skeletal partitions dividing corallite into radial sections - speta project into the center of the calyx
Costa
when septa go outside the corallite
Columella
skeletal strucutre in the center of the corallite
Verrucae
small, cylindrical projections on skeletons, wart
Hexacorallia
Subclass Zoantharia
Order Actinaria
Sea anemones
Sea anemones are … and much larger than …
solitary polyps, hydrozoan polyps
Order Actiniaria Characteristics
-present in coastal waters throughout the world but more abundant in tropical waters
-live attached to the substrate or attached to jellyfish, ctenophores, and crabs
Body Shape of Actinaria
-Columnar shape with oral end and aboral end
-oral ends flares to form the oral disc which contians 8 to several hundred tentacles
-hydrostatic skeleton
-slit shaped mouth and ciliated groove (siphonoglyph) in oral disc
-upon contraction, a sphincter muscle contracts, the upper surface of the column is pulled over the oral disc
Gastrovascular cavity in Actinaria
–partitioned by radiating mesentries
-complete
-incomplete
-occur in multiples of 12
-mesenterial perforations in upper pharyngeal area help water circulation
Spirocysts
nematocyst, that have a sticky end for prey capture
Feeding in Actinaria
-some anemones feed on inverts, small fish, crabs; the prey is paralyzed by nematocysts, captures by tentacles, and carried to the mouth. the mouth is opened by radial muscles and prey is swallowed.
-others are suspension feeders - either cilia beat toward the oral disc or toward the tip of the tentacles; either way, tentacles finally sweep them into the mouths
Sea anemones have both …
commensal inverts and symbiotic zooxanthellae
Siphonoglyph
ciliated to aid in “swallowing, excretion, and water exchange”
Acontia
extensions of mesenterial filaments; has digestive function; can be used for aggression
Order Zoanthidae
-palythoa, zoanthus, epizoanthus, parazoanthus
-tentacles never pinnate
-zooxanthellae
-polyps may be solitary or colonial
-largely tropical and common reef inhabitants
-many are epizootic
-their oral disc is often very colorful
-commonly known as colonial anemones and button polyps
Palythoa
-Contains palytoxin, one of the most toxic non-protein, organic substances in the world
-tolerant to high sediment and high nutrient loaded areas
Ceriantharians
tube anemones, burrowing anemones
Ceriantharians Characteristics
-long, solitary elongated polyps
-they live in vertical tubes made of specialized nematocysts called ptychocysts
-prefer burrowing into soft mud or sandy substates with only their tentacles visible
-oral disk has two distinct whorls or tentacles; short labial tentacles and longer thin marginal tentacles, which are particularly well armed with nematocysts
-have only one siphonoglyph
-range is worldwide in tropical and subtropical areas
Order Antipatharia
black coral, thorn or wire coral
Antipatharia Characteristics
-used to be subclass ceriantipatharia
-thought to cure disease
-slowest growing corals
-colonial
-hawaii state gem
-tree like or stick like corals with a solid dark brown skeleton decorated with small spines or thorn
-rougher surface than gorgonians or hydroids
-polyp color gives colony a brown, yellow, green, orange, or white color
-feathery black coral has feather like branches
-most are deep water
-panglobal; most common in tropics
-common on vertical cliffs or rocky outcrops in deep water with high current
-low rates of recruitment but low natural adult mortality rate and long life
-colonies have tiny polyps that are ringed with six nonretractile tentacles that contain cnidocytes
-lack zooxanthellae so depend on suspension feeding
-provide critical habitat for other organisms
Antipatharia Reproduction
-delayed first reproduction
-asexually by budding or fragmentation
-dioecious or gonochoric
-broadcast spawning of gametes
-sexual maturity for a New Zealand species was estimated at minimum of 31 years
Order Corallimorpharia
mushroom corals, bullseye, giant elephant ear
-discosomatidae
-ricordeidae
-corallimorphidae
-sideractidae
Corallimorpharia Characteristics
-do not produce a calcareous skeleton
-solitary polyps (deeper water) but frequently colonial in shallow
-tentacles are knoblike and arranged radially on a flattened disc
-broad, flat top, attached to a substrate with a stalk
-can grow together in a mat-like arrangment
-some are large enough to eat fish
-contains zooxanthellae
-contain nematocysts
-may produce mucus nets or chemical defenses
-fluorescent or irredescent tentacles and oral disc
Corallimorpharia Reproduction
-asexually through budding, longitudinal fission, pedal laceration or polyp bailout
-not much is known about sexual reproduction
How to distinguish within Corallimorpharia
- Presence or absence of surface tentacles and shape (verrucae – short
tentacle; papillae -bumps) - Presence or absence of bare margins along the edge or oral disc
- Absence or presence of marginal tentacles
- Absence or presence of column and stiffness of base
- Ability to move and trap animal prey
- Maximum size
- Color
- Degree of colinality
- Absence or presence of spirocysts (sticky, non-penetrating
nematocysts)
Family Ricordeidae
- Short, berry-shaped tentacles
- Most common color is green
- Nematocysts and zooxanthellae
- Not as hardy as other mushroom corals
- Semi-aggressive
- Also eats small invertebrates
- Many are polystomatous
- Tentacles cannot be withdrawn
- Column is reduced or absent
Coral reefs are nutrient deserts - can zooxanthellae provide everything the corals need?
Zooxanthellae capture light and transfer energy to form sugars. Other nutrients must come from another source.
Most nutrient exchange takes place …
close to the reef
Definition of Biogeochemistry
the study of biologically mediated chemical compounds that influence geological processes
Nutrient concentrations are actually … on a reef and reflect the ocean around the reef
low
Biogeochemical pathways of a reef reflect those of a …
plankton system
Coral reefs show substantial rates of … but have no tendency toward exportation of nitrogen
nitrogen fixation, nitrification, and denitrification
Coral reefs are very efficient at recycling nutrients but the system as a whole is still …, but changes in nutrient input would change community structure
nutrient limited
… ecological efficiency is necessary to support the biomass of higher trophic levels
very high
Michaelis-Menton kinetics
theory of mass transfer, rate of enzyme reactions
… is taken up at mass transfer
limits. So actual net growth of a reef
community is controlled by mass
transfer of …
phosphate
Redfield ration
ratio of carbon, nitrogen and
phosphorus are pretty uniform through the oceans – 106:16:1
DON can be used to estimate coral reef …
metabolism