lecture 19 Flashcards
Until recently, what was considered the sister taxa of Hexapods
Myriapods
What is the common name for Hexapods?
Insects
What is the common name for Myriapods?
Centipedes
Where has recent discovery placed Hexapods on the phylogentic tree of life?
Within Crustaceans
What has the new clade of Crustaceans called/
PanCrustaceans
What are Tagmata?
Segmented bodies
What is the tagmata most commonly found in arthropods?
generally they have three segments comprising of:
Head (cephalization) - eatting and sensing
thorax: locomotion
Abdomen: Digestion and reproduction.
True or False:
Some Taxa within Arthropods have a combined head and thorax, what is it called and is this true?
It is called Cephalothorax
True
What Taxa am I describing?
- 1 pair of antennae
- 1 pair of compound eyes
- Has many biramous limbs.
The Trilobita
What dose it mean to be biramous?
to have 2-branched limbs.
When did the majority of trilobita wiped out?
During the end-permian extinction event roughly 280MYA
What is the basic body plan of crustaceans?
They have the following: 2 pairs of antennae biramous limbs compound eyes They have a cephalothroax They are covered by a carapace.
What dose the root word -cephalo- mean>
Head.
What is a Carapace?
shield that covers dorsal and lateral sides.
What are the main mouth parts of Curstaceans?
They are mandibles
What are mandibles?
Single-segmented biting/chewing.
What is the exoskeleton of Crustaceans re-enforced with?
Calcium carbonate.
What dose the root word -crust- mean?
crunchy
How do crustaceans preform gas exchange?
Through gills
How do fully terrestrial Crustaceans perform gas exchange?
they use a tracheae.
Most Crustaceans are sexed, what is the exception?
Barnacles, they are hermaphrodites
How dose sperm transfer occur within Crustaceans?
Through Copulation and intromission.
What is Copulation?
When the male places sperm in or on the females sperm-receiving organ.
What is intromission?
The male part goes inside the female part
How do most of the females of Crustaceans Handel their eggs?
They brood their eggs until they hatch.
True or false:
Some freshwater and terrestrial spp of Crustaceans are direct developers
True!
How do most Crustaceans develop through their life cycle?
Most of them have an indirect life cycle with a larval stage.
What is the most common larval stage of Crustaceans?
They are anuplius.
What are the four forms of nurtent gathering in Crustaceans?
- Filter feeders
- Scavengers
- Predators
- Commensals or parasites
What is a ecologically unsound way of gathering Crustaceans?
Through bottom-trawling.
What is the main reason bottom-trawling is unsound?
It has a 75% bycatch (fish that get thrown back)
What are common Hexapods?
Insects and spring tails
What are common Myriapods?
Centipedes and millipedes
What are the FOUR shared features between Hexapods and Myriapods?
- they have one pair of antennae
- they have mandubles
- they have a tracheae
- they have uniramous limbs.
What dose it mean to have uniramous limbs?
Having one set of legs per segment
True or false:
Pancrustaceans and myriapods all have mandibles as mouth parts.
True.
What is the defining feature of Hexapods?
They are 6-legged arthropods.
What dose the root word -hex- mean?
6
What class is included within Hexapods (gotta love them :D)
insecta
What is the second most important class within Hexapods?
collembola
What is the morphological structure of Hexapods?
-They have clear and consistent Tagmata
Collembola are entognathous
Insecta are ectognathous
What is found on each of the segments of tagmata within Hexapods?
head: 1 pair of antennae
Thorax: 3 pairs of jointed legs
abdomen: has no paired jointed legs
What dose it mean to be entognathous?
It means that the mandeibles are enclosed by the cheeks.
found in collembola
What dose the root word -ento- mean?
in(side)
What dose the root word -gnath- mean?
jaw
What dose the root word -ecto- mean?
out(side)
What dose it mean to be ectognathous?
Mean that your mandibles are not enclosed in cheeks.
this is found in insecta.