Author Archive

yes, there ARE marine insects

Thursday, May 10th, 2012

Possible Halobates specimen, sitting on a beach in Hawaii. Photo by Cory Campora. See the original at Flickr.

I started drafting a blog post several months ago about marine insects, in response to several then-recent statements like “there are no marine insects” and “insects never invaded the ocean”. Of course there are marine insects! There’s even a whole edited volume about them. My two favorite marine taxa are Chathamiidae (Trichoptera; eggs are laid in starfish!) and Hermatobatidae (Heteroptera; coral treaders!). They’re definitely worth reading more about.

Well, a group of pelagic insects—Halobates sea skaters (Heteroptera: Gerridae)—have been highlighted in the news this week, thanks to an interesting article by Goldstein et al. (online early at Biology Letters). Goldstein et al. show that the ever-increasing amount of plastics pollution in our oceans (the expanding plastisphere) has resulted in an increase in Halobates sericeus egg density (more places for them to lay their eggs) and now presents an interesting opportunity to study changes in the ecology of these insects and their prey/predators. Even Science ran a story about this research.

It’s great to see that marine insects are getting some press. Maybe I won’t need to finish this draft anytime soon.

a story from the archive

Wednesday, May 9th, 2012

I’ve been organizing my vast document archive this week, in preparation for my upcoming move, and I found this story I wrote back when I first arrived at NCSU. Context: In December 2007 I was asked by the students to be a panelist for a departmental holiday party skit, modeled after NPR’s Wait Wait … Don’t Tell Me. We had a “bluff the listener” segment, where someone listens to three stories and identify the one that is real. Here’s the story I told.

Call it serendipity, but when Dr. George Nixon of the British Museum fell asleep with an alarm clock near his pan traps while camping in Peru he discovered a new method for collecting certain parasitic Hymenoptera. His pans filled with tens of specimens of the euphorine braconid genus Elaterophaga, a parasitoid of adult click beetles previously known from only one reared specimen. Suspecting that the ticking sound mimicked that of click beetles righting themselves and that this was the source of the attraction Nixon experimented with more refined designs – including a model that employed a wind-up toy’s motor and two pieces of wood that slap together. The snapping trap was so successful that it not only brought in more species of Elaterophaga but also several genera of scelionids that parasitize click beetle eggs. Nixon published his design along with a survey of elaterid parasitoids in a 1955 issue of Entomological News. European entomologists refer to this mechanism as the click trap, but to my American colleagues it will always be the beloved, if not broadly useful, “clap trap”.

Is it real? You decide.

Insect Morphology Seminar – extended phenotype

Friday, April 27th, 2012

(written by Ann Carr)

Today we had our last seminar session, and I have to say that most of us were sad to see it end. This has been an amazing class and one of the better seminars offered. We sure hope all of you bug enthusiasts have enjoyed following our discussions! We have learned some much, and hope that you learned a little too. Last weeks seminar topic was insect products with a focus on galls. We had a full house this week, so lucky for you there are quite a few papers to go over. So let’s get started! PS need to give a big “Thank You!” to Trish and Steve for making some amazing curry and banana pudding, which might I add pair together very well.

Insect morphology now infiltrates every aspect of our lives. Here, a wasp-inspired cookie crumb garnish adorns a delicious banana pudding. Yummy and educational!

Keith got us started with a paper discussing the phylogeny of the galling aphid species Eriosomatini. This paper suggests that the evolution of galling aphid species is largely affected by the presence of host plant species. Species divergence is closely associated with host plant extinction and subsequent diversification of host plant types. This theory makes sense because of the critical association galling aphids have with their host plants. By comparing insect and gall morphological features the authors are able to construct a very nice evolutionary tree and identify Eriosomatini’s closest sister species.

I followed with a paper examining survival strategies of Contarinia galling midges. Because the midges are most susceptible to mortality when they are in gall-forming phase, they have evolved long diapause periods in the soil. Contarinia midges have 99% of their population laying dormant in the soil. Their diapause periods last 10-17 years depending on emergence. This allows the species to survive extinction if all of their galling populations are exterminated. The authors also believe that because of the limited availability of their host plant, that the Contarinia midges must establish a long-lived population to evade extinction.

Matt talked about a paper that examined what happens when galls are on leaves that are aborted by the host tree. The authors compared two gall structures, simple and complex. They were able to conclude that the more complicated gall structures were able to survive on the forest floor once aborted by the host tree, unlike the simple gall structures. This was described as the “Green Island Effect” where the exterior tissues of the leaf died, though the tissue surrounding the complex gall remained green and viable for a period of time after falling from the host tree.

Trish found a paper that studied sexually dimorphic galls of scale insects. In the genus Apiomorpha females produce round circular galls and males produce long tubular galls. They were also interested in why two populations of the same species produced different galls. The authors did studies to see if the two populations were making different galls because of the host plants they were using. They concluded that the insect determines the gall shape, not the host plant, and during their research they discovered genetic variances between these two populations and re-established them as two separate species.

Andrew discussed a paper that examined why caddisfly larvae line their cases with pine needles. The caddisfly were not using the pine needles for camouflage or defense, but were actually using the pine needles to help anchor and stabilize themselves when confronted with strong or turbulent water currents. The authors note that caddisfly without pine needles would spin and rotate more than caddisfly with pine needles attached to their case.

Steve followed with a paper that talked about silk production in male dance flies. Dance flies are the first type of fly found to produce silk. Structurally their silk looks very similar to silk produced by Lepidopterans. Though, genetic analysis showed there were no similarities in composition between the dance fly silk and other insect silk products. This means that this is an entirely different silk from what is typically found. What was really neat was the purpose of the silk. Male dance flies would skim the surface or water sources and use the silk as a net to collect diatoms, and present the package as a nuptial gift to females.

Colin presented our last paper of the semester, which actually was a review on lac insects and the harvesting of shellac. Lac insects feed on the sap of trees and produce shellac while laying eggs. The shellec is scraped of the trees, harvested and finished all by hand. Variations in shellac are dependent on lac insect species. The paper also discussed the lac agriculture in India and Thailand, cultural demands, and threats to shellac harvesting.

Well that about sums it up for today. Thanks for following along. We hoped you enjoyed it as much as we did!

Hexapod Haiku 2012 – honorable mention (poet over 13)

Thursday, April 26th, 2012

The following five haiku, in no particular order, earned honorable mention in this year’s Hexapod Haiku Challenge. We thank the poets for sharing their artistry and congratulate them on their works:

spring rain
aphids busy
being green
Ernest J. Berry
Picton, New Zealand
dying bumblebee
my friend bends over and asks
are you all right?
Gail Ingram
Christchurch, New Zealand
all the insects
I’ve killed–waiting
in the other world
Dave Russo
Cary, NC
Molting is a must
The vehicle is renewed
Same old heavy soul
Anish Thakkar
Raleigh, NC
roach legs
by the cat bowl
long winter night
Dave Russo
Cary, NC

Hexapod Haiku 2012 – honorable mention (poet under 13)

Thursday, April 26th, 2012

We had two honorable mention entries from the poets under 13 this year, which I present below (a bit late – sorry!) in no particular order. Congratulations!

Tree Lobster

Big as a man’s arm
Living on a little bush
Not knowing they’re there

Smriti Sridharan
Raleigh, NC

(the above poem is about the Lord Howe Island stick insect, Dryococelus australis, which was recently rediscovered on Ball’s Pyramid; the judges appreciated the relevance of this poem and the contrast between large and small)

Insects flying in
Summer sun searching
for anything they want
Harmen Alleyne
Urbana, IL

(the judges liked the freedom expressed in this poem; as a child you’re always told what to do, but insects have the freedom to do whatever they want!)

Hexapod Haiku 2012 – runner-up (poet under 13)

Thursday, April 19th, 2012
Stinkbugs like to stink
Please, never squish a stinkbug!
Also, don’t catch them
Mary-Katherine Thompson
Raleigh, NC

Judges’ Comments: We delighted in reading this whimsical plea, which captures the spirit of youthful conversation: insistent and awkwardly constructed, yet humorous. The request in line two (we can almost hear the *crunch* of that poor insect in some unsuspecting hand) is almost negated by the non sequitur in line three. Don’t squash that bug! In fact, don’t even catch it in the first place. The protagonist longs to share her knowledge of these offensive insects, and we are captivated by her enthusiasm and the promise of relevant advice.