ENTM 335 Exam 1

Systematics vs Taxonomy

Systematics is the study of evolution of life, past and present, while taxonomy is the present day description and characteristics of animals

1, 2, 3

monophyletic (ancestral species and all descendant species), polyphyletic (group consisting of members of multiple groups), paraphyletic (ancestral species and some of its descendant)

goal of modern organism classification

to describe and classify organisms into monophyletic groups

Homology

similarities between structures and genes due to shared evolutionary history

homologous characters

Character: a general heritable feature (ex. eye color)

State: specific condition that the character takes (ex. brown)

Plesiomorphy: ancestral character state, symplesiomorphy (shared) apomorphy (derived)

Who came up with species

Carl Linnaeus with Linnaeus’s systema naturae edition 10 in 1758. included biological, morphological, evolutionary, and phylogenetic species concepts

biological species concept

species are groups of interbreeding natural populations that are reproductively isolated. Only works for sexual reproduction

Morphological species concept

species are groups of individuals with shared morphological characters. Going on just looks leaves room for error

evolutionary species concepts

a species is a single lineage of ancestral descendant populations which has its own evolutionary history tendencies. Doesn’t help define species

Phylogenetic species concept

species are the smallest aggregation of populations/lineages diagnosable by a unique combination of character states in comparable individuals

when did arthropods first come about

around 520 mya in the ancient precambrain seas

where do wings come from? how many times did they evolve?

We believe that wings came from the pleural membrane in the mesothoracic region when bugs came to land and used them to glide down plants. evolved once

which is true and why: shrimp are bugs or bugs are shrimp

bugs are shrimp is true since insects are basically land crustaceans since evolutionary science places directly inside the crustacean family tree

what’s a xenocardia and its sister group

a type of evolutionary clade of crustaceans includes remipeda and cephalocarida, sister group is hexapoda

Tagmosis and its importance

the fusing and modification of segments to form a specialized are of the body. important because its how insects developed their 3 body segments and how we have so many orders

apterygota

ametabolous, wingless, mouthparts exposed: archeognatha and zygentoma

pterygota

winged insects, all except apterygota

palaeoptera

“old wings”, lack wing folding mechanisms, direct flight muscles, hemimetabolous: odonata and ephemeroptera

neoptera

“new wings”, indirect flight muscles: all except apterygota and palaeoptera

exopterygota

external wing development, hemimetabolous, no pupal stage: plecoptera, blattodea, orthoptera, dermaptera, hemiptera, mantodea, hemiptera, thysanoptera

endopterygota

internal wing development, holometabolous, pupal stage: coleoptera, diptera, hymenoptera, lepidoptera, etc

polyneoptera

“many new wings”, under exopterygota: orthoptera, mantodea, blattodea, etc

paraneoptera

“some new wings”, under exopterygota: ONLY pscodea, thysanoptera, hemiptera

trilobita

two legs in one hole, all dead, three body segments

crustacea

clade: mandibulata class: remipedia, cephalocardia. two pairs of antennae

hexapoda

clade: mandibulata class: insecta, entognatha. 3 segments, 3 pair legs, 1 pair antennae,

myriapoda

clade: mandibulata class: diplopoda, chilopoda. lots of legs, two segments (trunk and head)

chelicerata

Class: merostomata, arachnida. scissor mouth parts, two body segments

Order Thysanoptera: Thrips Characteristics

very small, rasping-sucking, wings are narrow and elongated with long fringe-like hairs, suborders: Terebrantia vs Tubulifera

Suborder Terebrantia

abdomen ends in a conical tip, females have a blade-like ovipositor, FW membrane has 1-2 longitudinal veins

Suborder Tubulifera

abdomen ends in a tubular tip, females lack an ovipositor, FW membrane lacks veins,

Family: Thripidae

common thrips, terebrantia, concical abdomen tip, females have blade-like ovipositor bent downwards, FW with 1-2 longitudinal veins, mostly plant feeders,

Family: Phaeothripidae

tubular thrips, tubulifera, abdomen tip tubular, no ovipositor, no veins on FW, some predators and plant feeders, larger and stouter bodied that are usually black

Social thrips

dispersers: reproduce, initiate new galls, grow galls, and provide extensive brood care

soldiers: defend galls against other thrips and kleptoparasites, have lower reproductive output and cannot initiate or grow galls

Order Psocodea

two major groups, Psocoptera and Phthiraptera

Suborder: Psocoptera (booklice and barklice) characteristics

small soft-bodied insects, face bulging, antennae long and slender, chewing mouthparts, prothorax often reduced, when wings present held roof-like over body, tarsi have 2-3 segments, cerci absent

Infraorder: Phthiraptera (true lice) Characteristics

small, wingless, dorsoventrally flattened ectoparasites of birds and mammals, chewing or piercing-sucking

Family: Menoponidae

chewing lice of birds, broad triangular head, short clubbed antennae concealed in grooves, 2 tarsal claws

Family: Philopteridae

Chewing lice of birds, more square/rectangular head, exposed 5-segmented antennae, 2 tarsal claws

Family: Trichodectidae

chewing lice of mammals, rounded or blunt-conical head, exposed 3-segmented antennae, 1 tarsal claw

Family: Pediculidae

blood-feeding human head and body lice, elongate body, thorax narrower than abdomen, short similar sized legs, pincer-like claw

Family: Pthiridae

human crab louse, short body, thorax about as wide as abdomen, second and third pairs of legs wider and stouter than the first

Order: Hemiptera Characteristics

piercing-sucking mouthparts, four piercing stylets derived from the mandibles and maxillae, stylets are enclosed in a flexible labium which acts as a sheath, maxillae fit together to form a food channel and a salivary channel, feed on fluids

Suborder: Heteroptera (true bugs)

beak arises from the front of the head, FWs hemeyltra (hardened at base and membranous at tip), HWs membranous

Suborder: Auchenorrhycha (cicadas, hoppers, spittlebugs)

beak arises from the back of the head, antennae are short and bristle-like, tarsi usually have 3 segments, many are active jumpers or strong fliers, all are plant feeders

Suborder: Sternorrhycha (psyllids, aphids)

beak arises between the fron coxae, antennae are usually long and threadlike, tarsi have 1-2 segments, many are relatively inactive or sedentary, all are plant feeders

Family: Hydrometridae (water measurers)

Heteroptera, very slender, stick-like body and long legs, head approximately as long as thorax, wingless, slow-moving shoreline/water-surface predators

Family: Gerridae (water striders)

Heteroptera, elongated body with very long middle/hind legs that act like oars, front legs grasp prey, water-resistant hairs on tarsi, anteapical claws, predators/scavengers

Family: Belostomatidae (toe biters/giant water bugs)

Heteroptera, large flattened oval insects, raptorial front legs, swimming hairs on middle and hind legs, short/stout beak, females lay eggs on males’ backs

Family: Nepidae (waterscorpions)

Heteroptera, long caudal breathing tube formed from modified cerci, raptorial front legs, ambush predators

Family: Corixidae (water boatmen)

Heteroptera, dorsally flattened, forewings have dark crosslines, hind legs are oar-like and fringed with hairs, swim right-side up, front tarsi are spatulate and adapted to sweep up small food particles

Family: Naucoridae (creeping water bugs)

Heteroptera, broadly oval and flattened, front femora greatly thickened for grasping prey, found in quiet water, crawling on vegetation

Family: Notonectidae (backswimmers)

Heteroptera, swim on their backs under the water, dorsally convex or keeled body, long oar-like hind legs fringed with swimming hairs

Family: Gelastocoridae (toad bugs)

Heteroptera, oval flattened body and bulging eyes, resmeble small toads, thickened front legs grasp prey

Family: Saldidae (shore bugs)

Heteroptera, small, pval, often bulging eyes, wing membrane with 4-5 long closed cells, shoreline predators

Family: Reduviidae (assassin bugs)

Heteroptera, narrow head, thick 30segmented beak, predatory, front legs may grasp prey

Family: Miridae (plant bugs)

Heteroptera, largest hemipteran family, FW has a diagnostic cuneus and 1-2 closed cells, mostly plant feeders

Family: Tingidae (lace bugs)

Heteroptera, small and flattened, elaborate lace-like sculpturing and many closed wing cells, plant feeding can cause yellow leaf spotting

Family: Nabidae (damsel bugs)

Heteroptera, elongate, often brown, 4-segmented beak, no prosternal groove, beneficial predators in crops

Family: Anthocoridae (minute pirate bugs)

Heteroptera, small, typically black and white adults, partial cuneus, preadtors of aphids, mites, thrips, etc

Family: Cimicidae (bed bugs)

Heteroptera, broad, flat, oval, wingless, blood-feeding on birds and mammals, hide in cracks and crevices

Family: Aradidae (flat bugs)

Heteroptera, extremely flattened, cruptic, usually under loose bark or in dead/decaying trees

Family: Pentatomidae (stink bugs)

Heteroptera, shield-shaped body, 5-segmented antennae, large traingular scutellum, strong defensive scent glands, mostly plant feeders

Family: Scutelleridae (shield-backed bugs)

Heteroptera, enlarged, rounded scutellum covers most of abdomen, plant feeders

Family: Lygaeidae (seed bugs)

Heteroptera, forewing membrane has 405 simple veins, most feed chiefly on seeds

Family: Coreidae (leaf-footed bugs)

Heteroptera, often have leaf-like expansions of hind tibidae, FW membrane has many simple veins, includes squash bug

Family: Rhopalidae (scentless plant bugs)

Heteroptera, smiliar to coreidae but often lighter, smaller, and with poorly developed scent glands, membrane has many veins

Corixidae vs Notonectidae

Heteroptera, corixidae swim right-side up, notonectidae swim upside down on their backs

Pentatomidae vs Scutelleridae

Pentatomidae large triangular scutellym, Scutelleridae enlarged rounded scutellum covers most of abdomen

Family: Cicadiae (cicadas)

Auchenorrhyncha, three ocelli, both wings membranous, males have tymbals for sound production

Family: Cercopidae (spittlebugs)

Auchenorrhyncha, oval body usually wider toward the rear, hind tibia has 1-2 stout spines along the outer edge, nymphs produce spittle from anal fluid to keep them moist and provide protection

Family: Membracidae (treehoppers)

Auchenorrhyncha, pronotum enlarged and often extends backward over the abdomen, pronotum may be thorn-like bulbous or spiny, many species mimic plant parts, oviposition can damage plants

Family: Cicadellidae (leafhoppers)

Auchenorrhyncha, small, head often wedge-shaped, hind tibia has a uniform row of many small spines along the outer edge, feed on leaves, some produce sounds

Family: Fulgoroidea (planthoppers)

Auchenorrhyncha, antennae arise below the eyes on teh side of the head, vertical ridge separates the antennae from teh front of the head, many species have unusual head shapes/produce waxy tails

Family: Psyllidae (jumping plantlice)

Sternorrhycha, small, resemble tiny cicadas, 10-segmented antennae

Family: Aleyrodidae (whiteflies)

Sternorrhycha, 2-3mm, resemble small white moths, 7-segmeneted antennae, wings covered in white waxy powder and held roof-like over the back

Family: Aphididae (aphids)

Sternorrhycha, small soft-bodied pear-shaped insects, have a pair of tube-like cornicles on the abdomen, winged and wingless

Family: Adelgidae (pine/spruce adelgids)

Sternorrhycha, small soft-bodied and similar to wooly aphids but w/o cornicles, may be covered with waxy material

aposematic coloration

defense strategy where unpalatable, toxic, or dangerous organisms use bright, conspicuous colors and high contract pattern to warn predators

Order Hymenoptera Characteristics

4 membranous wings, FW larger than HW, wing venation reduced varyingly, hamuli (tiny hooks on the fron edge of the HW that connect to FW) allow wings to function together during flight, chewing mouthparts

Symphyte Characteristics

abdomen broadly joined to the thorax, ovipositor saw or needle like, includes sawflies, horntails, and wood wasps, larvae are often plant feeders or wood borers

Suborder: Apocrita

abdomen narrowly joined to the thorax, forming a wasp waist, first abdominal segment is fused to the rear of the thorax (propodeum), apparent thorax called mesosoma, remaining abdomen is the metasoma, divided into informal Parasitica group and Aculeata

Parasitica

ovipositor typically exits before the tip of the abdomen and may remain extended, mostly parasitoid wasps, paraphyletic

Aculeata

ovipositor modified into a stinger, stringer is associated with a venom gland and is located at the abdominal tip, includes bees, wasps, and ants, monophyletic

jugal lobe

lobe on HW, size relative to M+Cu/submedian cell can help identify groups

Subantennal sulcus

groove running down from the base of an antennal socket toward the clypeal suture

Petiolate abdomen

abdomen attached by a narrow stalk

Pectinate antenna

antenna with comb-like branches or projections

Family: Cimbicidae

Symphyte, giant sawflies, large robust adults, antennae have seven or less segments and are clubbed/knobbed, larvae feed on leaves and curl into a spiral at rest

Family: Tenthredinidae

Symphyte, common sawflies, small to medium sized, antennae threadlike with 7-20 segments, forewing has one or two marginal cells

Family: Siricidae

Symphyte, horntails, large elongated cylindrical insects, have a horny spear-like projection at the end of the abdomen (not the ovipositor), females have long sturdy ovipositor, eggs are laid through bark in recently dead or dying conifer

Superfamily: Ichenumonoidea

Braconidae vs Incheumonidae, pronotum traingular laterally, antennae long filiform, metasoma attaches low near hind coxae, complete venation, ovipositor permanently exserted issuing before tip of abdomen

Family: Braconidae

braconoid waps, mostly small, FW had 0 or 1 M-Cu crossvein, metasomal tergites 2 and 3 are fused

Family: Ichneumonidae

ichneumonid wasps, range of small to larger and vary in shape, Fw has two M-Cu crossveins, have a horse-head or boot-shaped cell, formed by fusion of the first submarginal and 1M cells, metasomal tergites 2 and 3 are not fused, ovipositor is often long

Superfamily: Chalcidoidea

microparasitoids, wing venation greatly reduced by usually with characteristics Y-vein, pronotum quadrate laterally, body often sculptured, antennae usually elbowed, <13 segments, trochanters 2-segmented, ovipositor arises anterior to tip of abdomen

Family: Mymaridae

tiny, usually under 1mm, narrow, elongated, hair-fringed wings, unique head sulci, egg parasitoids, FW surface hairs are not arranged in rows

Family: Eulophidae

usually 1-2mm, 4 segmented tarsi, small straight front tibial spur, front and middle coxae widely separated, long marginal vein, parasitoids of eggs and larvae, male antennae are often pectinate

Family: Pteromalidae

wasp, usually 2-4mm, 5 segmented tarsi, front and middle coxae close together, medium length marginal vein, large curved front tibial spur, parasitoid or hyperparasitoids of multiple insect groups

Family: Chalcididae

usually 2-7mm, robust black and yellow, enlarged hind femora, often toothed, hind coxae enlarged, internal/external parasitoids

Family: Cynipidae

gall wasps, small globular with a shiny laterally compressed abdomen, antennae threadlike not elbowed, most induce plant galls or live as inquilines in galls formed by other insects