Brachiopods Flashcards
What is the phylum for Brachiopods
Brachiopoda
What do most brachiopods possess
Teeth
Sockets
Shells made out of calcium carbonate
Lophophore support structure
When did they evolve and are they around today
Cambrian period
Yes they are extant
What kind of symmetry does each valve show
Bilateral
What is the brachial valve
The smallest valve
What is the lophophore
is a fluid filled set of filaments lined with cilia, the cilia beat and generate currents to enable food parcels to become trapped
What is the muscle scar
An aberration on the inside of a shell, where a muscle was attached
What is a pedicle
Fleshy stalk made mainly of muscle, which attaches a brachiopod to the substrate
What is the pedicle valve
The valve which may have an opening for a pedicle to protrude
What is the pedicle foramen
The hole where a pedicle protrudes
What is the cardinal process
Part of the brachial valve where muscle is attached
What is the diductor muscle
The muscle for opening the valves
What is the brachidium
Lophophore support
What is the adductor muscle
The muscle for closing the valves
How did they feed
Filter feeders
They fed with aid of the lophophore (covered in cilia) as they beat it created currents which brings fresh water and food particles, trapping the particles and passed down to the groove of the mouth which they then ingested
What are the adaptations and reasons linked to turbulent water
A large pedicle valve-to support a large piece for attachment
Strongly ribbed valves-To strengthen shells against wave action
Folded or zigzagged margin-reduce the amount and size of sediment moving into the shell when open
A thick heavy shell-to provide extra stability on the substrate and prevent rolling
What are the adaptations and reasons linked to quiet water
May have a median fold or sulcus-to separate currents of water entering and leaving the animal
May have extension of the valves to form ‘wings’-Large surface area to prevent sinking into the sediment
Smooth or weakly ribbed valves-No need to make thicker
No pedicle opening-Not needed for attachment
What are the adaptations and reasons linked to a soft, muddy substrate
Valves late with large rising area-Provide large surface area to prevent sinking
One margin of the shell may be turned upwards, away from the sediment-To ensure that some part of the shell remains out of the sediment for feeding
What are the types brachiopods
Rhynchonellids
Spiriferids
Productids
Terebratulids
What is the geological time for Rhynchonellids
Ordovician to Recent
What is different about their hinge line (Rhynchonellids)
It is short and curved
What energy conditions did they liven and how did the structure of their shells help them (Rhynchonellids)
High-energy conditions
Their shells were strongly ribbed
How big is the pedicle and what does this mean (Rhynchonellids)
Small piece
Showing that they were attached to the sea floor
The commissure is what shape and why (Rhynchonellids)
Zigzagged
So edge of the shell stops larger particles getting in
What is notable about its fold and sulcus
Strong and well-developed
What is the geological time for Spiriferids
Ordovician to Jurassic
How are Spiriferids easy to identify (Spiriferids)
Long straight hing line which is so wide they look winged
What do they often have in the middle of each valve (Spiriferids)
A fold and a sulcus
What is so special about their lophophore support system (Spiriferids)
It is spiral shaped called spirella
Where they attached (Spiriferids)
No
Lay on the sea floor
What is the geological time for Productus
Devonian to Permian
What shape is their hinge line (Productus)
Straight
The pedicle valve is usually what (Productus)
Large and strongly convex
What kind of tubular spines do they have (Productus)
Hollow
Long spines
Is there an opening for the pedicle valve and what does this tell us (Productus)
No
Used the long spines to anchor itself
Geological time for Terebratulids
Devonian to Recent
What shape is its hinge line (Terebratulids)
astrophic being short and curved
Was it very streamline (Terebratulids)
Yes
What kind of environments did they live in (Terebratulids)
High-energy environments
