Studying Lucidota: Fireflies of Central Ohio


Starting from a very young age, I fell in love with insects and anything else that had zero, four or more legs. Despite growing up in the suburbs, my backyard and the nearby woods were my favorite places to be.  No rock or paving stone was left unturned while I searched for insects! However, what truly started me on the path I travel now was a short but inspiring TV show on Animal Planet.  Back when I was ten, Animal Planet ran a TV show called “Buggin’ with Ruud” staring Ruud Kleinpaste as he traveled the world to find unique insects.  Not only was the show educational, it was funny too!  He would handle all kinds of insects and arachnids and even gave demonstrations of how the bug’s senses and abilities would work on a human sized scale.  Ruud gave me a window to places I may never see in person and showed me just how fun it can be to be into bugs.  That’s how I knew I wanted to make my career in insects, and in some way or another, bugs would shape the rest of my life.

Link to special “Buggin’ with Ruud: World’s Biggest and Baddest Bugs” (2009) from YouTube (Thomas Clark Published on Jul 25, 2015) below:

https://youtu.be/reZDLN3EuW4

Fast forward another ten years, and I am now trying to make my career a reality here at The Ohio State University.  I enrolled in autumn of 2017, majoring in Entomology and it has taken me far deeper into the scientific world than I had ever gone before.  Courses like General Entomology 4000 have helped me to build a foundation of information about insect taxonomy and physiology, in addition to properly starting a collection.  Taught by Professor Joe Raczkowski, he engaged me in the course content. He hosted my first official collecting excursion in Hocking County. There I got firsthand experience catching, killing, and mounting specimens for my new collection, as well as a demonstration of the different traps used to capture insects.  More importantly, he helped me find opportunities that would expand my knowledge and give me a taste of the entomological world.

That is how I found my way to the Triplehorn Insect Collection in January 2018.  When I started volunteering, I was given several jobs to get me acclimated to the work done in the collection.  I helped organize moth specimens by family, sort specimens to order from bulk collecting bags, and used macro photography to image butterflies, just to name a few things. All these tasks gave me usable skills such as safe specimen handling, organization, and good note taking. However, it also introduced me to more options to explore in an Entomology career. From here, I talked to the collection curator Dr. Luciana Musetti and explained my interest in research.  I wanted to go in depth, and experience field and research work.  When she offered me a chance to contribute to the scientific community through a research project, I jumped at it.

My fellow research assistant Martha Drake and I, under the guidance of Dr. Natalia Molotievskiy and Dr. Musetti, are exploring the diversity of Lampyridae in Central Ohio. For those unfamiliar with Lampyridae, they are more commonly known as Fireflies/Lightning Bugs and are a large family of beetle. Our goals are to document the regional diversity of fireflies (using both morphology and DNA barcoding), their abundance, and seasonal distribution over the course of the year.  In order to do that we are collecting samples weekly at three nearby sites. We also will compare our findings with historical records from published literature and collections. Although Martha and I joined in only this year, the collecting for the project started way back in 2016.

We set up Malaise traps in three different locations: two on OSU’s Waterman Farm, and one near the Carmack parking lot. A Malaise trap looks like a tent with open sides, a dividing wall, and a funnel that leads to a collecting jar at the top.  It works by blocking the path of flying insects.  Their instinct is to climb up, where the funnel at the top directs them into a killing jar. Every Thursday Martha and I, with occasional help from our colleagues in the lab, go pick up the weekly samples and refill the killing jar with alcohol. Back in the lab, the bulk samples from the traps are kept in the freezer and sorted to insect order as quickly as possible. Sorting weekly Malaise trap samples is a lot of work and to accomplish that, Natalia, Martha and I have help from several assistants and volunteers working at the collection.

For the firefly project, we take the beetle portion of each sample, sort out the lampyrids and, using scientific keys, separate them into the various genera. We just finished that part of the work for the 2016 samples. Loads more to go for 2017 and 2018.

One of the Malaise traps (MT2) set up near a stream on the Waterman Farm property.
Credit: Hannah McKenzie

As part of our learning experience, Martha and I  each are focusing on a separate genus. Hers is Pyropyga and mine is Lucidota. In parallel with the collecting and sorting and identification, we also had to dig deep into the scientific literature to learn what was already known about these animals. Research about the genus Lucidota is crucial to understand them, but we also read broadly about the Firefly family — how they fit in the beetle tree of life, where they live, what they eat, how they reproduce, all is fair game and vital in building a foundation to refer to.

There are two species of Lucidota documented in Central Ohio, L. atra and L. punctata (Marvin Jr., 1965). Often referred to as “Black Fireflies”, both species have completely black elytron and lack a functioning light organ.  Ergo, they fly during the day and use pheromones to find mates.  While both species are similar in coloration, L. atra has distinct pale borders on the pronotum and is the larger of the two species (9-12 mm long).  L. puntata is much smaller (6-8 mm) and has a noticeably darker pronotum with darker red markings (Luk, et. al., 2011).  They both inhabit the same woodland/marginal fields, often near water.  Despite the similar habitats, L. atra is far more common than L. punctata.  Not much is known about either species since very few studies have been conducted on them.  However, review of the literature is an ongoing process and I will update with more information in future posts.

Martha (left), me (center), and Dr. Molotievskiy (right) extracting DNA from our samples in the lab.

We have now moved on to the next stage in the project: DNA barcoding.  After selecting my desired specimens, the voucher’s hind leg was removed and used in a different lab protocols.  First, the leg had DNA extracted through lysis of its cells.  To test if the DNA in solution was sufficient, a fluorospectrometer was used to quantify the amount of DNA in the vial after lysis.  Next, the DNA collected was amplified using a Polymerase Chain Reaction (PCR) protocol, which replicated the target mitochondrial strand of DNA. Using primers, and a “master mix” of nucleotides and enzymes, the DNA samples were placed in the PCR machine which ran the program for 35 of heating and cooling to allow the primers and enzymes to increase the DNA concentration.  There are many more samples to extract and amplify, but once complete the DNA will be sent to GENEWIZ for further analysis and sequencing.

References:

Luk, Stephen P.L., et. al.. “Fireflies of Ontario (Coleoptera: Lampyridae).” Canadian Journal of Arthropod Identification No. 16. June, 2011. ISSN 1911-2173.

Marvin Jr., Daniel. “A List of Fireflies Known or Likely to Occur in Ohio; With Special Notes on Species of Ellychnia.” The Ohio Journal of Science. v65 n1 (January, 1965), 37-42.

About the Author: Danny Philips is a second year undergraduate student in the Department of Entomology at The Ohio State University.  He hopes to continue his education following his bachelors degree with a special interest in arthropod disease vectors. He enjoys being outside and hunting for insects in his spare time, his favorite being the praying mantis.  When not looking for insects he likes to go fishing with his grandfather and to have campfires with friends.

(Unless otherwise specified, all pictures were captured by Dr. Luciana Musetti.)