Lec 11 Biodiversity III

Question 1

What is some general morphological trend that characterize teleost evolution?

Answer 1

Reduction and loss of parts. Either through simple loss or by fusion of two or more elements to form one.

Question 2

ethmoid region

Answer 2

the snout

Question 3

What are the ethmoid region of primitive teleosts like?

Answer 3

Extremely complex, consist of numerous separate ossifications and cartilaginous elements.

Question 4

Circumorbital bones

Answer 4

elements that surround and protect the eye

Question 5

Circumoribtal bones in primitive teleosts are usually

Answer 5

seven or more ossifications

Question 6

What is the ethmoid region like in highly dervied teleosts?

Answer 6

Elements of the ethmoid become lost or fused to three or four bones

Question 7

What happens to the caudal skeleton as is evolves?

Answer 7

Reduction, fuse and loss occurs. Primitive teleost i.e samonid is extremlely complex and goes through reduction as teleosts evolve.

Question 8

Where are the reduction of the caudal fin?

Answer 8

Hypurals, bones that bear the caudal fin rays. It went from 8 or 9 elements in primitive teleosts to a single solid bony plate in derived teleost.

Question 9

What do primitives tend to have more of and more variability of compared to derived taxa?

Answer 9

Primitive teleosts tend to have more vertebrae and more variability in vertebral counts compared to more derived taxa.

Question 10

Primitive abdominal vertebrae and caudal vertebrae proportions.

Answer 10

2/3 abdominal, 1/3 caudal

Question 11

More derived teleosts’ abdominal and caudal proportions

Answer 11

abdominal 1/2 caudal 1/2

Question 12

Highly derived teleosts, i.e percoids’ proportions of abdominal and caudal proportions

Answer 12

abdominal 1/3 caudal 2/3

Question 13

What are the teleost trends discussed?

Answer 13

1. shift in position of the paired
2. trend toward the development of spines, particularly in the dorsal, anal and pelvic fins
3. shift in func of upper jaw bones and development of an ascending process

Question 14

What are the 4 major lineages of teleosts that were evolving divergently?

Answer 14

1. osteoglossomorpha
2. elopomorpha
3. clupeomorpha
4. euteleostei

Question 15

Osteoglossomorpha aka

Answer 15

bony tongue fishes

Question 16

Osteoglossomorpha suborders

Answer 16

1. osteoglossoidei
2. notopteroidei
3. mormyroidei

most primitive of four primary teleost linages

Question 17

Osteoglossomorpha: Suborder osteoglossoidei

Answer 17

bony tongued, i.e Arawana, Arapaima

Question 18

Osteoglossomorpha: suborder notopteroidei

Answer 18

old world knifefishes, mooneyes, featherbacks

Question 19

Osteoglossomorpha: Suborder morymyroidei

Answer 19

elephantfishes

Question 20

What defines bony tongue fishes?

Answer 20

feeding mechanism: bite with tongues.

large tooth plate in floor of mouth called glossohyal plate.

It makes contact with teeth on a medial bone of cranium called parasphenoid.

Question 21

Major lineage: elopomorpha

Answer 21

contains tarpons and all true eels.

Two major groups: elopiformes and anguilliformes

Question 22

elopomorpha: elopiformes

Answer 22

tarpons, tenpounders and bonefishse.

Question 23

elopomorpha: angilliformes

Answer 23

true eels

Question 24

What defines elopomorphas?

Answer 24

They all share a unique larval stage called a leptocephalus.

Question 25

major lineage: clupeomorpha

Answer 25

herrings and herring like fishes

Question 26

clupeomorpha characteristics

Answer 26

silvery, marine, filter feeding fishes that inhabit well lit surface waters around the world

Question 27

What defines a clupeomorpha

Answer 27

have direct connection between the swimbladder and the ear that somehow enhances hearing.