Glossary
A
adductor (muscle) – a round, meaty muscle that bivalves uses to open and close their shell
aerobic – living or occurring only in the presence of oxygen
Algae – non-vascular plants that grow submerged in marine or freshwater environments
algivorous – feeding on algae as a primary food source
anoxic – without oxygen
anterior – the side of a clam – foot end (opposite of posterior)
aperature – (Arthropoda: Crustacea) The postero-ventral opening into the mantle cavity of barnacles.
(Mollusca) An opening at the last-formed margin of a shell, providing the outlet for the head-foot mass
apron – a small and short abdomen, which is bent up beneath a crab’s larger thorax
aquaculture – also known as aquafarming, is the farming of fish, crustaceans, molluscs, aquatic plants, aquaferalgae, and other organisms
aquafer -an underground layer of water-bearing permeable rock. Groundwater can be extracted using a water well
arthropod – an invertebrate animal having an exoskeleton (external skeleton), a segmented body, and jointed appendages
astaxanthin – a blood-red pigment produced naturally in freshwater microalgae
B
beak – the tip of each valve, the oldest part of the shell, generally pointed and near the hinge.
The general region of the beak is often called the umbone or umbo.
benthic zone – one of the ecological regions of a body of water. It comprises the bottom—such as the ocean floor or the bottom of a lake—the sediment surface, and some sub-surface layers
binomial – a biological species name consisting of two terms e.g Callinectes sapidus (blue crab)
bivalve – a freshwater or saltwater mollusk with a shell consisting of two rounded plates called valves joined at one edge by a flexible ligament called the hinge
brackish water – water that is intermediate in salinity between seawater and freshwater. Water is considered brackish if its salinity is between 0.5 and 30 ppt
branchial – relating to gills.
broadcast spawning – a form of sexual reproduction used by aquatic invertebrate animals where billions of sperm and eggs are spewed into the surrounding waters for fertilization
bolus – a mass of food preparation ready to be passed through the gastrointestinal tract
buccal – (Latin) of or relating to the cheeks or mouth cavity
buccal cavity – in gastropods, the area inside the mouth that houses the radula
buckram crab – a stage following papershell when the shell is starting to harden but is still pliable
buster (crab) – a crab in an advanced stage of molting, wherein the old exoskeleton (hard shell) has cracked under the lateral spines
byssal threads – the threads some bivalves such as mussels and scallops secrete with their foot to attach the shell to a rock or other substrate
byssus – a bundle of strong, hair-like (byssal) threads originating from posterior end of (often reduced) foot. Produced by byssal gland and extended from shell to attach to hard substratesre
C
calcareous – adj. – composed of, containing, or characteristic of calcium carbonate, calcium, or limestone; chalky – clam shells are made primarily of calcium carbonate
calcareous worms – (tube worms). a marine worm that encases itself in a tube made of calcium carbonate and attaches to stones and other hard objects (buoys, shells, outboard boat engines, etc.). They eat plankton, which they filter through a crown of feathery tentacles.
carapace – a hard, bony outer covering, such as the portion of the exoskeleton covering the head and thorax of a crustacean
cardinal tooth – on a bivalve shell, a (usually relatively short) tooth below the beak of the umbo, and usually aligned with the beak . Contrasted with lateral tooth
carnivore (carnivorous) – an animal that eats other animals or animal matte
catotenoid – any of a class of mainly yellow, orange, or red fat-soluble pigments, including carotene, which give color to plant parts such as ripe tomatoes and autumn leaves
cephalothorax – the fused head and thorax of many crustaceans.
chelea – (cheliped) a large pincer-like claw of such arthropods as the crab and scorpion
chemosensory organs – two protruding structures on top of the head that use olfactory cues to guide their navigation behavior
chitin – a nitrogen-containing polysaccharide, related chemically to cellulose, that forms a semitransparent horny substance and is a principal constituent of the exoskeleton, or outer covering, of crustaceans and insects
chitinous – a tough, protective, semi-transparent substance forming the principal component of arthropod exoskeletons. The teeth of a snail’s radula is comprised of the same material
cilia – plural for cilium – tiny hairlike structures that project from the surface or certain cells and are
capable of a sweeping rhythmic motion in certain organisms.
ciliary – of or relating to cilia (using cilia)
cirrus (plural cirri ) – a long, thin structure in an animal similar to a tentacle but generally lacking the tentacle’s strength, flexibility, thickness, and sensitivity
cloacal chamber – chamber which passes excess water and waste from an oyster into the environment. In addition, it houses the adductor muscle and rectum.
columella – the hidden central axis of a whelk or snail shell that a series of whorls are wound around.
commensalism – species interactions in which one species benefits, but the other is neither harmed nor helped
conifer – tree that bears cones and evergreen needlelike or scalelike leaves.
crustacean – one of a large group of arthropods which includes animals such as crabs, lobsters, crayfish, shrimp, krill and barnacles.
crustacyanin – a carotenoprotein biological pigment found in the exoskeleton of lobsters and crabs responsible for the color blue
cteidium – (c is silent) – a hinge having marginal projections that resemble the teeth of a comb (characteristic of Ark clams)
ctenodont hinge – (c is silent) – a hinge having marginal projections that resemble the teeth of a comb (characteristic of Ark clams)
cuticular (adjective) -(cuticle) – the noncellular, hardened protective covering of many invertebrates.
D
dactyl – crab claw has two fingers, one is moving and one is not. The dactyl is the movable finger, and it rotates about a hinge axis to the next fixed finger
debeard – the process of removing byssal threads from a mussel (in preparation for consumption)
decapods – having ten (deca) feet (pods) – characteristic of crabs
deciduous (adjective) – a tree or shrub shedding its leaves annually. Often contrasted with evergreen.
denticles – the arrangement of teeth on the radula of a snail
desiccation – (from Latin de- “thorougly” + siccare “to dry”. the state of extreme dryness, or the process of extreme drying
detention pond (basin) – an area that has been excavated near tributaries of rivers, streams, or bays to protect against flooding for a limited period of a time
detritus – an accumulation of disintegrated organic material or debris – (Biology) the organic debris formed from the decay of organisms
diapause – spontaneous interruption of the development of certain animals, marked by reduction of metabolic activity
diploid – containing two complete sets of chromosomes, one from each parent
triploid – containing three homologous sets of chromosomes.
dormant (dormancy) – in a state of minimal metabolic activity with cessation of growth, either as a reaction to adverse conditions or as part of an organism’s normal annual rhythm
dorsal – the side of a clam – location of the umbo, beak and hinge (opposite of ventral)
doubler – mating crabs; the male carries the soft-shell female crab, which has just completed its terminal molt, beneath it
dye – a colored substance that chemically bonds to the substrate to which it is being applied
E
ectotherm – an animal that is dependent on external source of body heat (cold blooded)
electromagnetic spectrum -the range of frequencies (the spectrum) of electromagnetic radiation and their respective wavelengths. The colors red green blue (RGB) when they are combined create white light.
encruster – something that forms a crust, e.g. barnacles on a rock
endotherm – an animal that is dependent on or capable of the internal generation of heat (warm blooded)
equivalved – both valves being equal in size and shape.
estuary – a zone along a coastline where freshwater systems and rivers meet and mix with salt water
eutrophication – excessive richness of nutrients in a body of water (frequently due to runoff from the land) which causes a dense growth of plant life and death of animal life from lack of oxygen.
exoskeleton – an external skeleton that supports and protects an animal’s body, in contrast to the internal skeleton (endoskeleton) of, for example, a humae.g.
F
fascile – a small or slender bundle of leaves or flowers growing crowded together (as of pine needles).
feces– waste from digested food.
G
gametes – reproductive cells. Female gametes are called ova or egg cells, and male gametes are called sperm
ganglion (pl ganglia) – a network of cells forming a nerve center in the nervous system of an invertebrate
gastropod – (meaning stomach-foot) a mollusk that typically has a large foot for crawling and a single coiled shell that covers the soft body. Snails and whelks are gastropods.
genus – a rank in the classification of organisms, below family and above species
gill – a respiratory organ in aquatic organisms whose function is to extract dissolved oxygen from water and excrete carbon dioxide. The gills of some species such as hermit crabs have adapted to allow respiration on land provided they are kept moist.
gonochoristic – having separate sexes. Eggs are fertilized internally
groundwater – when rain falls on dry ground, it can soak into, or infiltrate, the ground. This remains in the soil, where it will eventually seep into the nearest stream
H
hemoglobin – a protein that is carried by red cells. It picks up oxygen in the lungs (or gills in the case of the Blood Ark) and delivers it to the peripheral tissues to maintain the viability of cells
herbivore – (Latin: herba, vegetation ; vorare to devour) a species that eat plants as their primary food source – herbivorous
hermaphroditic – hermaphrodite – possessing both male and female reproductive organs, structures, or tissue
hibernation – a state of minimal activity and metabolic depression in warm blooded animals (endotherms)
hinge – the shell of a bivalve is composed of two parts, two valves which are joined together by a ligament, usually with a set of interlocking “teeth” collectively known as the hinge.
hypobranchial gland – a gland producing mucus as well as biologically active compounds.
The cephalopod ink sac is a modified hypobranchial gland.
I
inequivalved – two valves of unequal size and shape
intracellular – existing, occurring, or functioning within a cell
intertidal zone – the area where the ocean meets the land between high and low tides
invertebrate – an animal without a backbone
L
labial palps – a pair of fleshy appendages on either side of the mouth of certain bivalve mollusks
larva (plural larvae) – a distinct juvenile form many animals undergo before metamorphosis into adults
lateral tooth – on bivalve shells, a usually relatively long tooth extending more or less parallel to the dorsal shell margin; separated from cardinal teeth by a space. Called anterior lateral teeth if anterior to the beak of the umbo; posterior lateral teeth if posterior to the beak
laviparous – bearing and bringing forth young that are larvae
lingual ribbon – another name for radula
ligament – an elastic, multilayered structure joining two valves of shell dorsally, typically posterior to beak.
littoral – of, relating to, or situated or growing on or near a shore especially of the sea
littoral zone – In coastal environments, the littoral zone extends from the high water mark, which is rarely inundated, to shoreline areas that are permanently submerge
M
macroalgae – a classification of algae that are defined according to the size of the plant where the body of the plant is large enough to be observable to the eye
mantle – (Latin pallium) the fleshy or membranous outgrowth of the body wall which secretes the shell
mantle cavity – a cavity formed by the mantle skirt, a double fold of mantle which encloses a water space
marginal teeth – (also known as anterolateral margin) spiny-like projections on the side of a crab’s carapace for protective purposes and in some cases an actual defense against attack
megalopa (megalopae, pl.) – final larval stage between the zoea and juvenile stage
metabolic energy – the processes that underlie food intake, burning the food to release energy, and storing the excess for the time of energy shortage
metamorphosis (metamorph) – when the larval stage is terminated by metamorphosis and the transition to the early juvenile stage, which resembles a miniature of the adult form
microalgae – a classification of algae that are defined according to the size of the plant where the body of the plant is small enough that it requires magnification to observe.
midgut —the portion of the intestine between the stomach and rectum
molt – the process by which a blue crab grows larger by periodically shedding its smaller shell
morula – a stage of clam embryotic growth – derived from the Lat in word for mulberry
mucous membrane secrete mucus. “Mucus” is the noun and “mucous” is the adjective
murex – a genus of medium to large sized carnivorous predatory tropical sea snails. Marine gastropod molluscs in the family Muricidae, commonly called “murexes” or “rock snails”.
N
nacre – the shiny, pearly lining on the inside of some bivalve shells. Sometimes called “mother of pearl
nauplius larva – the first planktonic larval stage of most marine and some freshwater crustaceans
nocturnal – an animal behavior characterized by activity during the night and sleeping during the day.
nudibranch – shell-less colorful mollusks. They are different shapes and sizes live in the low tide and eat sponges. The word “nudibranch” comes from the Latin nudus “naked” and the Ancient Greek βράγχια (bránkhia) “gills
O
odontophore – a structure in the mouth of most mollusks which supports the radula. It is drawn backward and forward in the process of breaking up food
omnivore – (Latin: omni all, everything; vorare to devour) a species that eat both plants and animals as their primary food source – omnivorous
operculum
– (gastropod) – a disc of calcium phosphate and mucilage secreted by snails over the aperture of their shells
– (arthropod) – barnacle – two movable plates that open for feeding and breathing, closing for protection and water retention
– (arthropod) – horseshoe crab – the first of the six pairs of book gills that covers and protects the other five pairs of gills.
osphradium – the olfactory organ in certain mollusks, linked with the respiration organ. Its main function is to test incoming water for silt and other possible food particles
ostracum – (gastropod) the calcareous (calcium carbonate) part of the shell beneath the periostracum
oviparous – producing young by means of eggs that are hatched after they have been laid by the parent.
P
pallium – the mantle – Latin word meaning mantle, robe or cloak
palp – an appendage found near the mouth in invertebrates (also see labial palps)
papershell crab – a crab that has recently molted and who’s shell has stiffened but is not yet hard
pelagic -in the water column; the open water above the sea floor
peeler crab – hard crab with a fully formed soft-shell beneath. ready to begin molting
periostracum – a thin organic coating or “skin” which is the outermost layer of the shell of many shelled animals
phenotypic plasticity refers to some of the changes in an organism’s behavior, morphology and physiology in response to a unique environment
photosynthesis – the process through which plants and algae generate their food. In this process carbon dioxide is converted into organic compounds, more specifically sugars, through the energy coming from sunlight
phytoplankton – microscopic organisms that live in watery environments. They live near the surface where there is sufficient light for photosynthesis . An example would be green algae. “Phyto” is the Greek word for “plant”
pigment – a colored material that is completely or nearly insoluble in water.
More important than their reflection of light is the ability of pigments to absorb certain wavelengths.
pincers – claw -a grasping structure on the limb of a crustacean or other arthropods
plankton – microscopic organisms that live in watery environments, both salty and fresh. “Plankton” is Greek for “made to wander or drift”
planktonic – of or relating to plankton. Free floating.
planktotrophic – feeding on or gain sustenance from plankton
pleopod – one of the paired abdominal appendages of certain aquatic crustaceans that function primarily for carrying the eggs in females and are usually adapted for swimming (see swimmerets)
posterior – the side of a clam – siphon end (opposite of anterior) Protein is the basic component of living cells and is made of carbon, hydrogen, oxygen, nitrogen and one or more chains of amino acids.
PPT – parts per thousand – a measure of salt content in water. Ocean water 35 parts salt dissolved in 1000 parts water (35 ppt). Fresh water, no salt 0.00 ppt
Predator – an organism that lives by preying on other organisms
proboscis – an elongated appendage from the head of an animal. The most common usage is to refer to the tubular feeding and sucking organ of certain invertebrates. In simpler terms, a proboscis is the straw-like mouth.
protandrous – having the male reproductive organs come to maturity before the female. The opposite of protogynous.
protein – the basic component of living cells and is made of carbon, hydrogen, oxygen, nitrogen and one or more chains of amino acids.
protandric – having male sexual organs while young, and female organs later in life
protobranch – “first gills.” – a subclass of bivalves (considered primitive) with lungs that are used only for oxygen exchange and not for feeding.
pseudofeces – feces-like deposits released by bivalves. As a bivalve filter feeds, rejected materials are gathered by cilia and mucus on the gills and swept out as pseudofeces, while food particles are transported to the mouth. Feces are waste from digested food.
R
radula – a flexible tongue-like organ in certain mollusks, having rows of horny teeth on the surface
radulae – the plural form of radula
retention pond (basin) -an artificial lake typically surrounded by vegetation and continually contains water treating incoming stormwater runoff by allowing particles to settle and various types of vegetation to take up nutrients
rhizome – a horizontal, usually underground stem that often sends out roots and shoots from its nodes
rostrum – Latin for “beak”- in crustaceans, the forward extension (or horn) of the carapace in front of the eyes.
S
salinity – the concentration of dissolved salts in water, usually expressed in “parts per thousand” (ppt)
sally crab or she-crab – immature female, distinguished by a triangular-shaped apron
SAV – Submerged Aquatic Vegetation – vegetation that lives at or below the water surface. An important habitat for young fish and other aquatic organisms
scutum pl. scutua – the two triangular opercular plates nearest the cephalothorax (the lower external triangular plate)
seafood – any sea animal or plant that is served as food and eaten by humans. Seafoods include seawater animals, such as fish and shellfish (including mollusks and crustaceans)
sedge -a grasslike plant with triangular stems and inconspicuous flowers, growing typically in wet ground
seed – refers to clams and oysters that are too small to harvest, but it generally refers to juvenile clams and oysters that have recently set.
septum – in biology, a septum (Latin for something that encloses; plural septa) is a wall, dividing a cavity or structure into smaller ones.
sequential hermaphroditism occurs when the individual changes its sex at some point in its life.
serotinous cones – very thick, hard cones that are literally glued shut with a strong resin that can hang on a pine tree for years. Only when a fire sweeps through do these heat-dependent cones open up and release seeds
sessile – lacking the ability of self-locomotion and is predominantly immobile. Attached to a substrate
shed – either the empty shell or the process of casting off the shell.
siphon – the part of a clam’s (or mussel’s) anatomy that draws in water (incurrent siphon) to get food and oxygen and expels waste (excurrent siphon)
siphonal canal – an indentation or channel that accommodates the siphon in some gastropod shells
slough – the discarded “old” shell of a crab after it has molted
sook – a mature female crab, distinguished by its bell-shaped apron. Regionally, the apron is said to resemble the dome of the nation’s Capitol building
sp. – The abbreviation “sp.” is used when an actual specific species name cannot or need not be specified. The abbreviation “spp.” (plural) indicates “several species”
spat – a recently metamorphosed oyster that has attached to a surface. The term may be applied to any small oyster.
spawn – (spawning) involves females releasing ova (unfertilized eggs) into the water column while males simultaneously or sequentially release spermatozoa (sperm) to fertilize the eggs
spermatophore – a protein capsule containing a mass of spermatozoa, transferred during mating in various insects, arthropods, mollusks, etc.
spermatheca – a sperm reservoir that collects sperm from the male in the course of several matings, connects with the oviduct, through which eggs are carried to the outside. The sperm can remain alive and viable in the fluid medium of the spermatheca for several years
sponge crab Female crab carrying an egg mass
sublittoral – the subtidal zone below the low tide line; permanently immersed. The sublittoral zone extends to the point where the continental shelf drops
substrate – the base on which an organism lives. With the Latin prefix sub-, “below”, substrate refers to a layer under something else. (foundation)
subtidal zone – the marine zone below the intertidal zone a protein capsule containing a mass of spermatozoa, transferred during mating in various insects, arthropods, cephalopod mollusks, etc.that remains submerged at low tide; generally only refers to near-shore or coastal areas
subwatershed – Any of several parts of a watershed that drains to a specific location
supralittoral – the zone extending from the high-tide line toward dry land, only underwater during unusually high tides or storms
swash zone – an area of a beach where water washes up on shore after an incoming wave has broken. This action causes sand and other light particles to be transported up the beach
swimmerets – one of the paired abdominal appendages of certain aquatic crustaceans, such as shrimp and lobsters that function primarily for carrying the eggs in females and are usually adapted for swimming (also called pleopod)
symbiotic relationship – an evolved interaction or close living relationship between organisms from different species, usually with benefits to one or both of the individuals involved
T
taxodont hinge – teeth and sockets are small and numerous. They are arranged in a row on each side of the shell near the beak, on both valves.
taxonomic – concerned with the classification of things, especially organisms.
Tekhelet -Hebrew – a blue-violet or turquoise dye used in clothing and tapestries
telson – the last segment in the abdomen, or a terminal appendage to it in crustaceans and embryonic insects
tergum pl. terga – one of a pair of internal opercular plates in barnacles (the upper external triangular plate)
terminal molt – the final molt, usually associated with the female at the time mating takes place
terrestrial – living or growing on land; not aquatic.
thoracic – relating to the thorax.
tortion (gastropod) – the rotation of the visceral mass, mantle, and shell 180˚ with respect to the head and foot of a larval gastropod.
trapezoid – a four-sided polygon and with one pair of parallel sides opposite to each other
trapezium – a four-sided polygon which has exactly one pair of parallel sides opposite to each other
triploid – containing three homologous sets of chromosomes.
diploid – containing two complete sets of chromosomes, one from each parent
trophic level – the position an organism occupies in a food chain. (e.g. 1-plants 2-herbivores 3-carnivors)
trocophore – The planktonic larva having a roughly spherical body, a band of cilia, and a spinning motion
turbidity – a cloudiness or haziness of water caused by sediment or foreign particles being stirred up or suspended
turion – a type of bud that is capable of growing into a complete plant
Tyrain purple – a reddish-purple natural dye. Made from a secretion produced by predatory sea snails in the family Muricidae, rock snails (originally known by the name ‘Murex’).
The name Tyrian refers to Tyre, Lebanon.
U
umbilicus – the hollow cone-shaped space within the whorls of a coiled mollusk shell
umbo – the oldest section of the clam shell with subsequent shell growth radiating out from it. It is commonly known as the “beak”
unconfined aquifer – (water table) water seeps from the ground surface directly above the aquifer. it is not overlain by any confining layer but has a confining layer at its bottom
univalve – a freshwater or saltwater mollusk with a single shell, usually spiral and can hold the whole animal inside
V
valve – one of the two calcareous shell elements secreted by the mantle covering left and right sides of the soft body. The two valves are joined dorsally by a hinge and ligament
Vascular plants (tracheophytes) differ from the nonvascular (bryophytes) in that they possess specialized supporting and water-conducting tissue, called xylem, and food-conducting tissue, called phloem.
velinger – the term veliger comes from the word velum. A velum is a ciliated lobe that helps certain larvae swim, feed and breathe
ventral – the side of a clam where shell growth continues (opposite of dorsal)
vestigial – (of an organ or part of the body) degenerate, rudimentary, or atrophied, having become functionless in the course of evolution.
visceral mass – In a mollusk, the largest part of the soft body which includes the digestive and reproductive systems
visceropallium – the vascular mass
W
wampum – small cylindrical beads made from polished shells formerly used by certain Native American peoples as currency and jewelry or for ceremonial exchanges between groups
water column – The water located vertically over a specific point or station
watershed – a land area that channels rainfall and snowmelt to creeks, streams, and rivers, and eventually to outflow points such as reservoirs, bays, and the ocean.
whorl – a cluster of cells or tissue that surround another, that starts at the same plain of axis or starts at one point and wraps around that point in an expanding circular pattern
Z
zoea (zoeas, pl) -The larva that hatches from the female crab’s egg; multiple zoea stages are followed by the megalopa stage.
zooplankton – plankton that consists of animals, including small crustaceans, fish larvae, corals, rotifers, sea anemones, and jellyfish
