Tropical Marine Invertebrates Phylum Arthropoda - bu people [PDF]

subphylum TRILOBITOMORPHA subphylum CHELICERIFORMES class CHELICERATA subclass ARACHNIDA (ticks, mites, scorpions, spide

42 downloads 28 Views 1MB Size

Recommend Stories


Phylum Arthropoda
If you want to become full, let yourself be empty. Lao Tzu

phylum arthropoda genel özellikleri
If you feel beautiful, then you are. Even if you don't, you still are. Terri Guillemets

Marine Invertebrates
The best time to plant a tree was 20 years ago. The second best time is now. Chinese Proverb

Arthropoda
We can't help everyone, but everyone can help someone. Ronald Reagan

Marine Biology Phylum Sipunculans: Peanut Worms 1 Phylum Sipunculans
Never let your sense of morals prevent you from doing what is right. Isaac Asimov

arthropoda
Love only grows by sharing. You can only have more for yourself by giving it away to others. Brian

Invertebrates
Courage doesn't always roar. Sometimes courage is the quiet voice at the end of the day saying, "I will

Invertebrates
Keep your face always toward the sunshine - and shadows will fall behind you. Walt Whitman

Arthropoda, Chelicerata
The only limits you see are the ones you impose on yourself. Dr. Wayne Dyer

Phylum Cnidaria
I cannot do all the good that the world needs, but the world needs all the good that I can do. Jana

Idea Transcript


Tropical Marine Invertebrates CAS BI 569

Phylum ARTHROPODA by John R. Finnerty

Phylum Arthropoda Well over 1 million described extant species Four critical bodyplan features. Chitinous exoskeleton Segmented body plan Tagmatization Jointed paired appendages Profound changes in “axial complexity” occur during Arthropod evolution.

Whither the Coelom? The rigidity of the body wall (the sclerotized chitinous exoskeleton) was accompanied by other major changes to the body plan with important biomechanical ramifications. peristaltic locomotion using the coelom as a hydrostratic skeleton is no longer possible loss of circular body wall muscles extreme reduction of coelom—remnants found in the reproductive system and excretory system new large spacious body cavity, the hemocoel.

A Generalized Arthropod

Exoskeleton composition — Arthropods Epicuticle

Lipoprotein Lipids

Procuticle

Chitin (a polysaccharide) + associated proteins

Functional Specialization of Segments Functional Redundancy

Functional Specialization

Fusion of Segments (Tagmatization)

“head”

“thorax”

“abdomen”

Tagmatization

Phylum Tardigrada “water bears”

Onychophora

Phylum Arthropoda subphylum TRILOBITOMORPHA subphylum CHELICERIFORMES class CHELICERATA subclass ARACHNIDA (ticks, mites, scorpions, spiders, etc.) subclass MEROSTOMATA order Eurypterida (extinct sea scorpions) order Xiphosura (5 extant species of horseshoe crabs) class PYCNOGONIDA subphylum CRUSTACEA subphylum HEXAPODA class INSECTA class ENTOGNATHA (e.g., springtails) subphylum MYRIAPODA

subphylum Trilobitomorpha Originated in the Cambrian and went extinct in the end-Permian extinction, 250 million years ago. Anterior-posterior furrows divide body into 3 lobes. Dorso-ventrally flattened. The anterior section is covered by a head shield. This head section bears eyes. Each segment posterior to the mouth has a pair of biramous appendages. The outer ramus bears setae, and is specialized for swimming, breathing, or feeding. The inner ramus lacks setae, and is specialized for walking. In the earliest trilobites, all the appendages were nearly identical. In later forms, some appendages differentiated and even lost one ramus.

Trilobite Anatomy

subphylum Cheliceriformes two tagmata the anterior PROSOMA (cephalothorax) the posterior OPISTHOSOMA (abdomen)s CHELICERAE— the most anterior appendages on the prosoma are modified into claws (e.g., horseshoe crabs) or fangs (e.g., spiders) PEDIPALPS — second pair of appendages on prosoma used for prey manipulation WALKING LEGS — fours pairs follow the pedipalps on the prosoma. Appendages on the opisthosoma are typically modified for respiration (e.g., the gills of horseshoe crabs of the book lungs of spiders).

subclass Merostomata, order Eurypterida “sea scorpions” originated in the Cambrian (~510 MYA) perished in the end-Permian extinction (248 MYA) possible the largest arthropods that ever lived, up to 2 meters in length.

Limulus Anatomy

subclass Arachnida spiders, scorpions, ticks, mites, whip scorpions ~73,000 species almost all terrestrial opisthoma appendages modified into spinnerets in spiders or pectenes in scorpions (a sensory appendage) respiration by tracheae or “book lungs”

Spider Anatomy

subphylum Crustacea head, thorax, and abdomen head comprises five segments 2 pair of antennae 1 pair of mandibles 2 pair of maxillae thoracic appendages maxillipeds (food manip.) pereopods (walking legs) abdominal appendage pleopods

Malacostrocan Anatomy

subphylum Hexapoda, class Insecta very conserved segmental arrangement 19 segments five head segments with five head appendages antenna clypeus mandibles maxillae labrum 3 thoracic segments 11 abdominal segments “for every human alive, there are an estimated 200 million insects” —Brusca & Brusca

Smile Life

When life gives you a hundred reasons to cry, show life that you have a thousand reasons to smile

Get in touch

© Copyright 2015 - 2024 PDFFOX.COM - All rights reserved.