Actinopterygian Relationships IV Biology of Fishes 10.11.12
Overview
Presentation Topics
Review (Actinopterygian Relationships III)
Actinopterygian Relationships IV : Percomorpha
Actinopterygian Relationships Actinopterygian Relationships Actinopterygian Relationships
Paracanthopterygii (cods, anglers, cavefishes, relatives)
Acanthopterygii (spiny-finned fishes) - Mugilomorpha (mullets) - Atherinomorpha (silversides, flyingfishes, liverbearers and rel.) -Percomorpha (perch-shaped fishes)
Acanthopterygii Actinopterygian Relationships
Acanthopterygii (spiny-finned fishes)
Most diverse group of bony fishes; ~15,000 species
Two major synapomorphies
Ascending process – dorsal extension of premaxilla
Most highly developed pharyngeal dentition and function based on new muscle and bone attachments
Ctenoid scales
Physoclistous gas bladder
2 dorsal fins (1 spiny-rayed, 1 soft-rayed)
Pelvic and anal fin spines
Pelvic fins forward, pectoral fins laterally positioned
Acanthopterygii Actinopterygian Relationships
Acanthopterygii (spiny-finned fishes)
Most advanced fishes, dominate shallow productive habitats of marine and many freshwater environments
Controversial phylogeny (follow Nelson 2006)
Actinopterygian Relationships
Paracanthopterygii (cods, anglers, cavefishes, relatives)
Acanthopterygii (spiny-finned fishes) - Mugilomorpha (mullets) - Atherinomorpha (silversides, flyingfishes, liverbearers and rel.) -Percomorpha (perch-shaped fishes)
pumpkinseed sunfish
Actinopterygian Relationships Actinopterygian Relationships
Percomorpha (“perch-shaped” fishes)
Most advanced clade of fishes
~13,000 species; primarily marine, many successful freshwater
Primary synapomorphy is anteriorly placed pelvic girdle attached to pectoral girdle directly or via ligament
Pelvic fin with anterior spine and 5 soft rays (typically)
Percomorpha (basal groups)
Stephanoberyciformes (whalefishes)
Beryciformes (squirrelfishes)
Zeiformes (dories)
Gasterosteiformes (sticklebacks, seahorses)
Synbranchiformes (swamp eels)
Scorpaeniformes (scorpionfishes, sculpins, relatives)
Percomorpha Percomorpha (basal groups)
whalefishes
dories squirrelfishes
swamp eels seahorses, sticklebacks scorpionfishes, sculpins Percomorpha
Stephanoberyciformes (whalefishes)
~75 species
Deepsea marine fishes
Primitive percomorphs, more caudal fin rays (18-19) than other percomorphs (typically 17)
Percomorpha
Beryciformes (squirrelfishes)
~144 species
Nocturnal marine fishes
Large eyes, head; also primitive caudal fin ray number (18- 19)
Includes commercially important orange roughy (mature in 20-30 years, live past 150 years)
Percomorpha
Zeiformes (dories)
~75 species
Primitive marine percomorphs
Protrusible mouths
Not well-classified in percomorpha based on morphologies
Percomorpha
Gasterosteiformes (sticklebacks, seashorses)
~280 species, primarily marine, small fishes
Dermal armor plates, small mouths
Sticklebacks very intensely studied (behavior, physiology, ecology, evolution)
Unique reproductive behavior – “pregnant males”
Percomorpha
Synbranchiformes (swamp eels)
~100 species
Primarily freshwater, eel-like fishes
Air-breathers
Lack most fins, in some cases all fins
Invasive species from pet trade
Percomorpha
Scorpaeniformes (scorpionfishes, sculpins, relatives)
~1500 species, primarily marine fishes
Phylogenetic placement in percomorpha debated
Many lack scales, possess numerous spines
Venomous lionfishes and stonefishes
Freshwater sculpins
Lumpfish (Cyclopterus) is most advanced
Percomorpha (advanced groups)
Perciformes (perch-like fishes)
Pleuronectiformes (flatfishes)
Tetraodontiformes (puffers, triggerfishes, relatives)
Percomorpha Percomorpha (advanced groups)
Perciformes Pleuronectiformes Tetraodontiformes triggerfish
yellow perch
parrotfish flounders & halibuts ocean sunfish Percomorpha
Perciformes (perch-like fishes)
Largest order of vertebrates – 160 families and over 10,000 species; more than 2/3 of all fishes
Rapid evolution ~20 million years
Marine (gobies, wrasses, seabasses) and freshwater success (cichlids, croakers, perches/darters)
Some of the most recognizable fishes
Perciformes Percomorpha
Pleuronectiformes (flounders, halibuts, relatives)
Asymmetrical morphology – both eyes on one side of head
Teeth, scales, fins, pigmentation differ between sides
Benthic, carnivorous, primarily marine; ~680 species
Important food fishes
Percomorpha
Tetraodontiformes (puffers, triggerfishes, relatives)
“four teeth”; many lack true teeth (possess modified jaw bone)
Most derived fishes, reduced bones, fins, morphology; ~360 species
Trigger mechanism in trigger/filefishes
Cartilaginous elements re-evolved (“come full circle”)
tetraodotoxin