Tuesday, October 31, 2017

Arthro-Pod Episode 33: The Horror of Parasitoid Insects!


Hi there bug lovers and welcome to our Halloween special! Today, Jody and Jonathan are featuring parasitoids, one of the most fascinating groups of insects! Their life cycles lend themselves to Halloween discussion as they are often reminiscent of the Alien in Alien, devouring victims from the inside out. 


Aphid mummies caused by a parasitoid braconid wasp (Photo Jody Green; UNL)

In the show we discuss the differences between parasites and parasitoids but here are some easy definitions if you are curious: 


Parasites: lives off another’s (host) benefits by deriving nutrients at host’s expense giving nothing in return

Some examples
External: leech, lice, fleas, ticks, mites
Internal: tapeworm, protozoan that transmits Malaria via mosquito vector, horsehair worms

Here is a horsehair worm leaving a mantis

Parasitoid: Usually insects that undergo complete metamorphosis such as wasps and flies, where the female lays eggs in or on the host and the larvae behaves like an internal parasite, developing using the host’s body for nutrients, but eventually kills the host by through the developmental process. 

Some examples
Parasitoid
Host
Description
Appearance
Braconid wasp
(Braconidae)
Sphingid caterpillar (Spingidae)

Eggs laid & free living in side hemolymph, emerge & spin cocoon on outside of caterpillar
Hornworm caterpillar has hundreds of larvae or cocoons on the outside of its body. Wasp is very small.
Aphidius sp.
(Braconidae)
Aphids (Aphididae)
Eggs laid on aphid, grows inside, killing it, pupation creates the mummy form, chews hole out of the rear end
In the same place where aphids are found, aphid mummies are swollen, tan, papery spheres with cornicles. Tiny wasps among aphids.
Emerald wasp/Jewel wasp (Ampulicidae)

American cockroach
(Blattidae)
Sting thoracic ganglion to paralyze, then sting head to disarm escape reflex, chews off half of each antenna, guides cockroach to burrow
Wasp is found in Asia & Africa. Metallic blue color, 2nd & 3rd pair of legs are bright red & enlarged
Scolioidea (Scoliidae)
Scarab beetles/white grubs, Japanese beetles (Scarabaeidae)
Burrows in ground to look for larvae, spins cocoon underground, locates host by kairomones like hydrocarbons, feces
Wasp has stout body, bright colors, black & yellow.
Cicada killer wasps (Crabronidae)
Cicada
(Cicadidae)
Catch cicada using sounds, provision burrows with paralyzed cicadas, overwinter as larvae, pupate in spring, emerge as adults in summer (no adults overwinter)
Largest wasp, often close to wooded area where cicadas can be found, females are very large solitary, males territorial but only has pseudo stinger.
Velvet ant
(Mutillidae)
Cicada killer
(Crabronidae)
Lay egg in nest cell of cicada killer when larvae pupates it consumes pupae (Hyperparasite)
Bright colors, females lack wings, coarse hair
Ichneumonid wasp
(Ichneumonidae)
Coleoptera, Lepidoptera, Hymenoptera  grub, larva or pupae
Inject eggs into hosts bodies or in larvae of other icheunmonids (Hyperparasite). Can use ovipositor to inject into wood boring larvae below bark
Slender waist, lots of antennal segments, some have long threadlike ovipositors
Tachinid fly
 (Tachnidae)
Caterpillars and other insect hosts

Robust fly with shiny or very hairy butt, feeds on flowers as adult

Emblemasoma sp. (Sarcophagidae)
Cicada
(Cicadidae)
Locates host by acoustically hunting male cicadas, drops 1-6 maggots at base of wings that burrow into body to feed, larvae use “oral hooks” to chew their way out to pupate in soil.
Flesh fly with red eyes, 3 dark stripes on thorax

Cicada killer wasp with hapless cicada victim (Photo Jody Green; UNL)

Not all parasitoids are wasps! Flies and beetles can parasitize as well! (Photo Jody Green; UNL)


Questions? Comments? 

Follow the hosts on Twitter @JLarson_UNL@JodyBugsmeUNL, and @MSkvarla36

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This episode is freely available on archive.org and is licensed under Creative Commons: By Attribution 3.0. http://creativecommons.org/licenses/by/3.0/




Beginning/ending theme: "There It Is" by Kevin MacLeod (incompetech.com) Licensed under Creative Commons: By Attribution 3.0

Wednesday, October 25, 2017

Arthro-Pod Episode 32: Are you afraid of insects


Hi there bug lovers! On today's show Jody Green and Michael Skvarla talk about fears surrounding our six-legged friends. For some people insects produce feelings of unease and the heebie jeebies! What is that brought them to this and is there any way to overcome it? These questions and more, answered today on Arthro-Pod!

Show notes for today: 


  • Entomophobia – Fear of insects
  • Common entomophobias or insect-related phobias:
  • Apiphobia or melissophobia – fear of bees
  • Spheksophobia – fear of wasps
  • Myrmecophobia – fear of ants
  • Acaraphobia – fear of mites
  • Arachnophobia – fear of spiders
  • Mottephobia – fear of moths


Phobias or fears are not just a dislike for insects or a certain insect, but a deep, persistent and unreasonable fear which elicits symptoms of anxiety (heart palpitations, sweating, trembling, nausea, loss of breath, dizziness) when presented with an entomological stimulus. 

Immersion therapy can involve exposing arachnophobes to spiders such as tarantulas


Causes of specific phobias could be a variety of factors including traumatic childhood experiences, medical condition, genetic predisposition, learned behavior, fear by association and/or an evolutionary or cultural response. 

Arthropods in U.S. Homes:


Some Insect Horror Films (if you are looking for a Halloween movie marathon!)
  • Them! The Naked Jungle 1954
  • Tarantula 1955
  •  The Deadly Mantis. The Black Scorpion,  Monster from Green Hell, Beginning of the End 1957
  • The Fly, The Spider, The Strange World of Planet X 1958
  •  Return of the Fly, The Wasp Woman 1959
  •   Body in the Web 1960
  •  Mothra 1961
  • The Deadly Bees 1966
  • Hives of Horror 1967
  • Genocide 1968
  •  Phase IV 1974
  •  Bug, The Giant Spider Invasion 1975
  • Squirm 1976
  • Empire of the Ants, Kingdom of the Spiders 1977
  • The Swarm, The Bees 1978
  • Phenomena 1985
  • The Fly 1986
  • The Nest 1988
  • The Fly II 1989
  • Arachnophobia 1990
  • Naked Lunch 1991
  • Ticks, Skeeter 1993
  • Mosquito 1994
  •  Mimic, Starship Troopers 1997
  •  Bug Buster 1998
  • Spiders, The Nest 2000
  • Arachnid, Mimic 2 2001
  • Eight Legged Freaks, Infested 2002
  • Mimic 3: Sentinel 2003
  • Insecticidal, Glass Trap, Killing Bee 2005
  •  In The Spider’s Web 2007
  • Infestation, Invicta 2009


Jody has meleagrisphobia – fear of turkeys

Mike has basophobia or basiphobia – fear of falling


Questions? Comments? 

Follow the hosts on Twitter @JLarson_UNL@JodyBugsmeUNL, and @MSkvarla36

Get the show through iTunes!

Subscribe to our feed on Feedburner!  


We're on Stitcher too! 


This episode is freely available on archive.org and is licensed under Creative Commons: By Attribution 3.0. http://creativecommons.org/licenses/by/3.0/




Beginning/ending theme: "There It Is" by Kevin MacLeod (incompetech.com) Licensed under Creative Commons: By Attribution 3.0

Thursday, October 19, 2017

Arthro-Pod Episode 31: Winter is coming for insects



Hi there bug lovers! On today's show Jody and Jonathan discuss how insects survive the falling temperatures of winter. While some may just wait out the cold as an egg, others may stick around as an adult form which can lead to negative interactions in our homes. How can we prevent invaders and which are the most likely to be found indoors? Tune in to find out!

Pictures of Jody's infamous five fall invaders (All photos copyright of Jody Green; Nebraska Extension):
Multicolored Asian ladybeetles, note the "M" on pronotum which stands for multicolored Asian ladybeetle

Conifer seed bug

Cluster fly with fine golden hair

Boxelder bugs clustered together trying to get inside


Brown marmorated stink bug adult, the latest invasive to Nebraska

Show notes on fall invaders

https://lancaster.unl.edu/hort/articles/2011/FallInvaders.shtml

https://communityenvironment.unl.edu/pest-month-fall-invaders


Questions? Comments? 

Follow the hosts on Twitter @JLarson_UNL@JodyBugsmeUNL, and @MSkvarla36

Get the show through iTunes!

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We're on Stitcher too! 


This episode is freely available on archive.org and is licensed under Creative Commons: By Attribution 3.0. http://creativecommons.org/licenses/by/3.0/




Beginning/ending theme: "There It Is" by Kevin MacLeod (incompetech.com) Licensed under Creative Commons: By Attribution 3.0

Wednesday, October 11, 2017

Arthro-Pod Episode 30: Get to Know the Brown Recluse


Hi there bug lovers! On today's show Mike and Jonathan are talking all about the infamous brown recluse! While this eight-legged animal may inspire fear in the heart of many, perhaps it is just misunderstood? Tune in to learn about where the brown recluse lives, what may actually be responsible for those gross pictures you see online, and how to identify if you have a brown recluse or not!

Helpful size comparison of brown recluse to an American quarter (Jim Kalisch; UNL Entomology)

Here are our show notes with some helpful quotations pulled by Mike:

"From the beginning, the diagnosis of brown recluse spider bite was based on supposition much more than fact"
http://www.labmed.theclinics.com/article/S0272-2712(06)00015-1/abstract


"2,055 brown recluse spiders...were collected...in a home in Lenexa, KS. Additional collections from more typically infested homes in Missouri and Oklahoma in 2001 yielded 45 and 30 brown recluse spiders, respectively. Despite these infestations, no envenomations of the inhabitants of these three homes occurred. Considering the levels of infestations with no bites in the homes presented here, nonendemic areas in the United States, which typically lack recluse spider populations and have had zero to few verified specimens of the spider, do not have sufficient numbers of brown recluse spiders to make envenomation a likely scenario."

"Brown recluse spiders are not found in Canada. Hobo spiders have not been reliably implicated in  dermonecrosis. Worldwide, spider-bite envenomation is an unlikely cause of dermonecrosis."

"In total, 1,773 arachnids [were submitted] from 49 states. Participants from states at least half within the known brown recluse distribution submitted Loxosceles spiders 32–89% of the time. From 25 of 29 states completely or almost completely outside of the range of Loxosceles spiders, no recluse spiders were submitted."

"The diagnosis of brown recluse spider bite is overused for dermonecrotic wounds of uncertain etiology"

"The medical community from non-endemic Loxosceles areas often makes loxoscelism diagnoses solely on the basis of dermonecrotic lesions where Loxosceles spiders are rare or non-existent."

"Among both physicians and the general public, the perceived threat of spider bites far exceeds the actual risk. The misdiagnosis of spider bites is given to a wide spectrum of dermatologic conditions, some of which are far more dangerous than a spider bite."
http://www.nejm.org/doi/full/10.1056/nejmra041184


The six eyes that help to ID a brown recluse (Jim Kalisch; UNL Entomology)

Questions? Comments? 

Follow the hosts on Twitter @JLarson_UNL@JodyBugsmeUNL, and @MSkvarla36

Get the show through iTunes!

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We're on Stitcher too! 


This episode is freely available on archive.org and is licensed under Creative Commons: By Attribution 3.0. http://creativecommons.org/licenses/by/3.0/




Beginning/ending theme: "There It Is" by Kevin MacLeod (incompetech.com) Licensed under Creative Commons: By Attribution 3.0

Wednesday, October 4, 2017

Arthro-Pod Episode 29: The Migration of Painted Lady Butterflies



Tune in to today's show where Jody and Jonathan chat about painted lady butterflies and the magnificent migration that has been occurring. Painted ladies, aka cosmopolitans, are found on nearly every continent on Earth and are a handsome mixture of orange, brown, and white.
While the monarch butterfly is the most famous migratory insect, painted ladies are also capable of showing off and traversing the country over successive generations.




Learn more about this butterfly from our friends at Iowa State:
http://vanessa.ent.iastate.edu/node/10482

Or contribute to the databanks of iNaturalist
https://www.inaturalist.org/ 



Questions? Comments? 

Follow the hosts on Twitter @JLarson_UNL@JodyBugsmeUNL, and @MSkvarla36

Get the show through iTunes!

Subscribe to our feed on Feedburner!  

We're on Stitcher too! 


This episode is freely available on archive.org and is licensed under Creative Commons: By Attribution 3.0. http://creativecommons.org/licenses/by/3.0/




Beginning/ending theme: "There It Is" by Kevin MacLeod (incompetech.com) Licensed under Creative Commons: By Attribution 3.0