Download Tropical insects

Species Richness is unequally distributed across taxa
Leuhea seemanii (Tiliaceae)
•163 species of beetles
Erwin, T.L. 1982. Tropical
forests: their richness in
Coleoptera and other
arthropod species. The
Coleopterists’ Bulletin
36:74-75
163 species of beetles associated
with the canopy of 1 tree species
163 beetle species X 50,000 tropical tree species
= 8.2 million beetle species
Beetles represent about 40% of all arthropod species
 Number of arthropod species in the canopy = 20 million
Adding ground and understory arthropods
Total number of arthropod species =
30 million
Species Richness is unequally distributed within insects
*5 ―Major‖ Orders account
for 84% of species richness
within Hexapoda
1.
2.
3.
4.
5.
Coleoptera ~ 350,000
Hymenoptera ~ 125,000
Diptera
~ 120,000
Lepidoptera ~ 150,000
Hemiptera
~ 90,000
Phylum Arthropoda
Tree of Life: http://www.tolweb.org
Arthropod shared characters:
•
•
•
Segmented animals
Jointed appendages
Exoskeleton – a hard cuticle composed of a polysaccharide Chitin
Secreted by epidermis – consequently they molt
Arachnida
Diplopoda
Parapoda
Xiphosura
Trilobita
Hexapoda
Crustacea
Crustacea
Epiclass: Hexapoda
•Fusion of 2nd maxillae into labium
•Fixed # ab segs @ 11 – Ancestrally
•Tagmosis – head, thorax, ab
(body segs unite to form tagma)
What makes things baffling is their degree of
complexity, not their sheer size; a star is
simpler than an insect
- Martin Rees, 1999 (The Scientific American)
Order: Protura - ―first – tail‖
•Minute (~ 0.5 – 1.6mm)
•Head conical, scraping mouthparts
•No eyes or antennae
•1st pair of legs – sensory
•12 abdominal segments (in adult)
•1 ab. seg. added each molt (9-11)
(anamorphic)
•Gonopore on Ab 11
•Rudimentary appendages
On 1st 3 Ab segs
Order: Protura
Biology
• ~ 500 species world wide
•Moss, rotting wood, soil, leaf litter etc.
•Thought to feed on mycorhizal fungus
•Biology poorly known
•Functionally “tetrapods”
•Virtually no fossils
Order: Collembola ―glue-wedge‖
Characters:
• Reduction of ab segs to 6 (appears fewer)
• Abdomen w/ sucker-like ventral tube – collophore (1)
retaining hook (3) and furcula (4), gonopore (5), anus (6)
• larval development epimorphic (no segs added)
Order: Collembola
Biology:
•9000 sp WW
•Most common „entognath‟
• 3 – 6 mm
• Feed on decaying matter, fungus, bacteria, pollen, feces, etc
• Very numerous – up to 100k per m3
Order: Diplura ―two-tail‖
• Two caudal filiments
• eyes, ocelli absent
• antaenna long
• Styli present on ab segs (1/2 – 7)
Order: Diplura
Biology:
• 1000 sp WW
•< 7mm usually
• Dwell in soil
• Biology poorly known
• No fossils
Class: Insecta
United by:
• Typically ocelli/compound eyes
• Ectognathous w/ mouthparts well
developed
• Thoracic legs w/ > 5 segs
• Ab ancestrally 11 segs w/
gonopore
female (8), male (9)
• Cerci present basally
• Gas exchange via trachea – many
modse
Book of Insect Records, University of Florida
http://entnemdept.ufl.edu/walker/ufbir/chapters/index_subject.shtml
The Apterygote Insects
Order: Microcoryphia ―small-head‖ – Jumping bristletails
Cylindrical body
• Compound eyes large and contiguous, ocelli always present
• 3 caudal filaments
Order: Microcoryphia
Biology:
• ~ 500 sp WW
•Many ecosystems
• Most nocturnal
• Active – can leap 25 cm!
Order: Thysanura
―fringe-tail‖
Characters:
• Compound eyes widely
seperated
• ~ 500 sp WW
Habitat: feed on starchy products
• Can be a problem for books,
bindings with glue,
•Look in the bathroom
Infraclass – Pterygota
Paleoptera (informal grouping)
Order: Ephemeroptera ―Short-lived‖
• 3100 sp WW
•Most basal extant lineage of winged insects.
• Mouthparts vestigial as adults and that phase lasts 1 day
• Aquatic larvae (not an ancestral condition)
• Feed chiefly on algae and detritus
The shortest adult reproductive life belongs to the female of the mayfly Dolania
americana (Ephemeroptera) which lives for less than five minutes after its final molt. During this brief
window, the insect mates and lays her eggs.
Order: Odonata ―tooth‖
Characters:
• 5500 sp WW
•All nymphs are aquatic and predaceous
• Highly active flying hunters
• Many aquatic environments
The giant African Dragonfly
Anax tristis has a wingspan
exceeding 133 mm
Order: Plecoptera ―folded/plaited-wings‖
Characters:
• 2000 sp WW
•Nymphs are aquatic
• Both adults and larvae feed on algae
Super Order: Dictyoptera
Orders: Mantodea, Blattaria, Isoptera (1800, 4000, 2900 sp WW)
Closely related but now it seems that Isoptera is a highly derived family of Blattaria.
Termites play an important
role in natural and managed
systems, where they
may help to recycle
nutrients and aerate the soil
Order: Gryllobattodea
• 41 sp WW
•Discovered in 1914
• 15-30 mm
• 25 sp WW
• Live in extreme environments
Order: Mantophasmatodea
• 1st described in 2001 from 30 my amber
• 20 - 30mm
• One family and 3 genera
• Predaceous
• S. Africa, now known for its endemism (~41 sp)
Order: Embiidina ―lively‖
• 500 sp WW
•Superficially resemble Plecoptera
•Produce silk from cellular glands on anterior basal tarsus
• Spend life in spun silken galleries in litter, soil, rocks, etc
• One introduced sp in NA is Parthenogenic
• Adult males do not eat
Order: Phasmatodea
• 3000 sp WW
•Slow moving herbivorous
• 2000 species WW
• Widely dist, but richest in the tropics
Using any criterion of measurement, certain
walking sticks (order Phasmida) are the longest
insects on earth. Of the phasmids, the champion
is a female Pharnacia serratipes that measured
555mm (nearly 22 inches) from extended fore
tarsi to extended rear tarsi.
Leaf katydid
Stick insect
Order: Orthoptera ―straight -wings‖
• ~ 20,000 species
• Known for their enlarged hind legs – jumping
• Many produce sound via stridulation
• Early branch in polyneoptera
• Herbivore – Omn – Predatory
The Desert Locust, Schistocerca gregaria,
forms the largest swarms. In early 1954, a
swarm that invaded Kenya covered an area
of 200km2. The estimated density was 50
million individuals per km2 giving a total
number of 10 billion locusts in that swarm.
Order: Dermaptera ―skin – wing‖
• ~ 2,000 WW
• modified forewings, under which the hind
wings fold
• largely nocturnal, feed on detritus but can
be a pest
Order: Zoraptera ―pure-wingless‖
• 32 sp WW
• < 3mm
• principal food is fungal spores – we think
• Can be found in „colonies‟ under bark
Order: Psocoptera ―rub small‖
• 4400 sp WW
• < 6mm
• Feed on spores, algae, molds, cereals
• Either gregarious or not
• Certain sp can vector fringed tapeworm of
sheep
Order: Phthiraptera ―lice – w/o wings‖
• 4900 sp WW
• Small wingless ectoparasites on birds and mammals
• Both chewing and sucking types, which are distinct
Order: Hemiptera
• 90,000 sp WW
• All life histories practiced
• Most diverse Hemimetabolous insects
• Sucking mouthparts
The aphid Rhopalosiphum prunifolia has the shortest
generation time: 4.7 days at 25°C.
The African
cicada, Brevisana
brevis (Cicadidae)
produces a calling song
with a mean sound
pressure level of 106.7
decibels at a distance of
50cm.
Order: Thysanoptera ―fringe‖
• 5000 sp WW
• 0.5 – 5mm
• Many feed on living plant material, some predators
• Metamorphosis is somewhat intermediate b/t Hemi and Holo – metabolous insect –
1st 2 instars – no visible wing pads and other features
• Very Numerous
Sub Division Endopterygota – Holometabolous insects
Order: Neuroptera ―nerve - wings‖
• 6500 sp WW
• Most larvae predaceous, many are aquatic (not lacewings)
• Adults weak flyers
• Some (Rhaphidioptera) are parasitic in spider egg sacks
Order: Coleoptera ―sheath - wings‖
• 350,000 sp WW
• ALL habitats exploited
The largest living insect species, by virtue of
having the greatest visible body mass and probably
weight, are the giant scarabs, Goliathus
goliatus, Goliathus regius, Megasoma
elephas, Megasoma actaeon, and the immense
cerambycid, Titanus giganteus. No clear winner
can be declared on the basis of objective data, the
candidates being nearly equal in this regard, but a
visual comparison of all of them, side by side and
scaled to maximum known size, may convince one
otherwise. The heaviest weight reliably reported
for any insect is 71 grams for the protected giant
weta, Deinacrida heteracantha, of New Zealand.
Australian tiger beetles, genus Cicindela, subgenus Rivacindela,
(Coleoptera: Cicindelidae) are the fastest running insects known.
The fastest, Cicindela hudsoni, can run 2.5 meters per second
(5.6 miles per hour).
Pyrophorus noctilucus
(Elateridae) is not only one of
the largest bioluminescent
insects, but it has also been
reported as having the greatest
surface brightness, 45
millilamberts.
Trunk and stem borers:
Buprestids, Cerambycids
etc.
Leaf miners: Buprestids, moths, flies,
butterflies
Seed predators:
Bruchids: palms: and tree distributions:
Janzen studied
-Scheelia rostrata (Palm)
-Seeds that fell close to adult were almost
all destroyed by bruchids
-Trees are hyperdispersed?
-Insects affect tree distribution
Bruchid beetles
Order: Strepsiptera ―twisted - wings‖
• 550 sp WW
• Parasitic on other insects
• Males winged, Females highly modified
• The Enigmatic Order
• Life cycles very complex
Order: Mecoptera ―long - wings‖
• 600 sp WW
• 9 – 25 mm
• Pronounced „beak‟
• Most generalized Holometabolous insect
• Complex mating rituals involving nuptial gifts
Order: Siphonoptera ―tube - wingless‖
• 2500 sp WW
• Small
• Compressed laterally
•Highly modified ectoparasites
• Adults depend on blood of warm blooded verts (w/ rare exception)
• Larval are free living feeding on organic matter
• Covered in stiff backward facing setae and spines
Order: Trichoptera ―hair – wings‖
• 11,000 sp WW
• Aquatic larvae live in various freshwater conditions
• Larvae construct cases out of material that is species specific
Order: Lepidoptera ―scale - wingless‖
• 150,000 sp WW
• Most recognizable and liked insect (at least butterflies)
• Larvae have large impacts on ecosystems (herbivory)
Thysania agrippina (Noctuidae:
Catocalinae), the white witch
moth, has the largest reported
wing span of any lepidopteran.
This neotropical species is
reported to attain wing expanses
of up to 280mm.
The swallowtail butterfly, Papilio dardanus,
occurs throughout most of Africa. While the
males maintain a typical swallowtail
appearance, the females occur in over thirty
different mimetic forms that clearly resemble
various species of two danaid genera.
Specialists
Generalists
Sphingidae
Saturniidae
Order: Hymenoptera ―god of marriage‖
• 125,000 sp WW
• Ants, Bees, Wasps, Sawflies
• Also have large impacts on ecosystems.
Based on overall length, the smallest
adult insect is a parasitic
wasp, Dicopomorpha
echmepterygis(Hymenoptera:
Mymaridae). Males of this species are
blind and wingless and measure only 139
µm in length.
Parasitoids
The largest broods reported in the literature are
for Copidosoma floridanum (Encyrtidae). This
cosmopolitan wasp is an obligate egg-larval
parasitoid of moths in the subfamily Plusiinae
(Noctuidae). Broods for this species commonly
exceed 2000 wasps/host. The largest brood reported
is 3,055 individuals.
ICHNEUMONIDAE
Neotropical Hymenoptera Course 2011
Anu Veijalainen
University of Turku, Finland. anuvei @ utu.fi
BRACONIDAE
CHALCIDOIDEA
Platynocheilus
Fig wasps (Hymenoptera: Agaonidae) show
incredible host specificity which is essential to
their survival in an obligate mutualism with
figs. Hybrids do not occur in figs and fruit not
pollinated is often aborted. A mistake by a
wasp entering the wrong syconium (receptacle
with multiple flowers) and ovipositing will
likely cause the demise of its brood.
Ants are everywhere.
Harvester ants in the genus Pogonomyrmex have the most toxic venom based on mice LD50 values,
with P. maricopa venom being the most toxic. The LD50 value for this species is 0.12 mg/kg
injected intravenously in mice, equivalent to 12 stings killing a 2 kg (4.4 lb) rat.
1/3 of the entire animal biomass of the Amazonian
terra firma rain forest is composed of ants and
termites, with each hectare containing in excess of 8
million ants and 1 million termites.
In Papua New Guinea, E.O. Wilson collected
172 species of ants in 59 genera in 1 square mile.
They are premier soil turners, channelers of
energy, predators, seed dispersers, etc.
Eciton sp. (Army ants)
La Selva: 18
4.5 per hectare
Protect .04 tons wet-weight leaves
per hectare per year.
Bala ant Paraponera clavata
Some ants eat fungus
Leaf cutter ant (Atta cephalotes)
The thing ants fear most (even the Bala ant): Flies (Diptera)
Phorid fly
-Parasitoid
-attack wounded (or otherwise
occupied) ants like Atta
-Larvae move into ant‟s head
to finish development
Order: Diptera ―two - wings‖
• 120,000 sp WW
• Pervasive
• Most agile flyers
• Hind wings reduced to halteres (gyroscopes)
• Exploit any and all niches
Napoleon’s army was defeated by typhus (vectored by lice).
1812 – over 600,000 troops vs. Russia’s 250,000
by the end of the year, this number was reduced to 20,000—most
of the deaths were at least partially due to typhus. The next year
only 3,000 of these men were alive and most were sick with typhus.
Mid-fourteenth century- about 1/3 of Europe’s population
Died in a relatively short amount of time due to the plague
(vectored by fleas)
Malaria (vectored by mosquitoes) afflicts between 200-300
million people and kills over 2 million per year. It is the
leading cause of death worldwide for children under 5.
Mosquitos
-misery
-pestilence
-pollinators
Tabanid (Horsefly)
Simulid (purujas or Blackflies)
Bloodsuckers
An unfortunate colleague‟s arm
Fruit Borers
Gall makers
Diopsid fly
Tachinid Flies
O‟dowd et al. :
What characteristics of top-predators in the tropics
are necessary for them to cause ecosystem “meltdown”
as defined by O‟Dowd et al.?
Craft et al.:
1. What is DNA barcoding and how can it help
with the taxonomic crisis and diversity studies?
2. Have Novotny and colleagues modified
their views of the relationship between
specialization and diversity on PNG?