Book Review: The Cicadas of North America

Chris Alice Kratzer begins her new book with a deeply personal memory and dedication, then proceeds to deliver another comprehensive treatment of a common, yet complex, category of insects: cicadas. The book is the second for Kratzer, whose debut work was The Social Wasps of North America. With memories of this spring’s periodical cicada event still fresh in the public mind, this book could easily eclipse the wasp book in popularity, but both volumes deserve your attention.

The Cicadas of North America is essentially a monograph of all members of the family Cicadidae found north of South America. The scientific community should certainly respect it as such. If this sounds intimidating for non-scientists, you need not fear. Kratzer is a master science communicator, with sincere empathy for those of us who avoided hardcore subjects in high school and college.

Part of the genius in her approach is that she is self-publishing through Owfly Publishing, a subsidiary of her company Owlfly, LLC. This allows her to set her own limits, if any, and prioritize what she sees as most important for her audience. She takes creative license that serves to enhance the readability and overall presentation of the book. The digital artwork alone is enough to recommend the book, but wait, there is more.

Kratzer’s trademark continues to be exceptionally thorough coverage of background information on life cycle, anatomy, evolution, classification, ecological relationships, and impacts on humanity, both positive and negative, past and present. Even if cicadas are not your favorite insect (but really, why are they not?), you will find yourself referring to the front of the book for understandable explanations of genetics, taxonomy, and other scientific concepts that apply broadly across all organisms.

Once again, Kratzer expands her region of focus to include Latin America as, ideally, all such manuals should in the interest of geographic accuracy that respects biomes but not borders. This might be the final nudge I need to renew my passport. I mean, look at that Sparse Emerald Cicada, Zammara smaragdula. A turquoise cicada (it is on the cover, too)?

Each digital rendering is split from left to right to show the degree of variation in color, density of markings, and other morphological features to help identify a specimen of either form. Some species are treated twice if they exhibit strong regional differences, with corresponding range maps delineating their geographic distribution. Everyone contributing reference photos, and community science records resulting from those images, is acknowledged on each species page.

If you are a stickler for minute details, and/or get hooked on studying cicadas yourself, the “taxonomic notes” in the back of the book give you the most current assessment of the standing of various species. Kratzer readily admits that what is in the book could be wrong, but there is no argument as to how much is completely unknown to anyone, at least in the community of Western scientists. The book is thus both a treatise and a booster designed to ignite further research.

If I sound like a paid shill, or an infomercial, I hope I can be forgiven for my enthusiasm for a quality example of natural history literature. Meanwhile, I hope Kratzer continues turning out more such references for whatever creatures catch her fancy. I’m subscribed to the Owlfly newsletter, so I should be among the first to know.

The Cicadas of North America is a hefty 573 pages, retails for $27.99 U.S., from the publisher, and is shipped in sustainable packaging from EcoEnclose. You can request a signed copy when you order.

Fly Day Friday: The Good Mosquito

Believe it or not, there is a mosquito species I look forward to seeing every year. You may think I'm crazy, but hear me out. There are at least three reasons to love elephant mosquitoes in the genus Toxorhynchites. They are pretty, beneficial in the larval stage, and do not bite as adults.

A male Elephant Mosquito

Elephant mosquitoes are also known as giant treehole mosquitoes, so you can sense a theme here. They are indeed large for mosquitoes, averaging about seven millimeters in body length. That does not include the mouthparts and antennae. Their long legs make them appear larger still. Why the name "elephant mosquito?" It may be a reference to the long, upcurved palps of the males, which suggest elephant tusks.

Notice the tusk-like palps (part of the mouthparts), and bushy antennae on this male.

There is no denying the beauty of our single North American species, Toxorhynchites rutilus. They are iridescent blue and purple, with silver and gold highlights, and white tips on the hind legs. It seems that no one photo captures all the colors all at once. Despite their brilliance, they are surprisingly cryptic in the dimming light of dusk, when they are most active (though they are considered day-fliers).

As their other name indicates, elephant mosquitoes breed mostly in water-filled treeholes. The larval stage, at least in later instars, is predatory on other aquatic insects, including....wait for it....the larvae of other mosquitoes. Yes, you heard that correctly, they are a natural biological control of the mosquito species that pose a threat to human health. The larvae are reddish in color, with a short anal siphon (bearing the spiracle that permits intake of air at the water surface), and a broad, black head with strong mandibles. There are four larval instars, an instar being the interval between molts.

The female Elephant Mosquito has straight palps, and simple bristle-like antennae.

The adult elephant mosquito has a distinctive proboscis, bent strongly downward near the middle of its length. Instead of using their beaks to draw blood from other animals, elephant mosquitoes of both sexes feed only on flower nectar. As flower visitors, they are also pollinators of wildflowers. Some other species in the genus may also feed on fruit juices, and honeydew (the sugary liquid waste of aphids, scale insects, and various planthoppers).

The female again, showing that long,sharply-curved proboscis.

Here in northeast Kansas, on the Missouri border, I have found Toxorhynchites rutilus only in late autumn, and only on the flowers of White Snakeroot. I have only seen them in our yard, in fact, but I am not usually exploring elsewhere as sunset approaches. The species ranges from the eastern half of Texas and Oklahoma diagonally northeast to southern Pennsylvania, Connecticut, and Delaware.

Can you tell which sex this one is?

There are roughly eighty species of Toxorhynchites, occuring mostly in tropical regions around the globe. Due to their unique appetite for other mosquitoes, they have been employed as biological controls for container-breeding mosquitoes in Japan, southeast Asia, the Caribbean, and in some cities in the United States.

Are you a new fan of elephant mosquitoes yet? If not, please see the resources and links below for additional information on the biology of these remarkable flies. Mosquitoes, like most insects, and people, defy neat categorizing as "bad" or "good." Entomology is a great place to learn lessons like that.

So handsome!

Sources: Alomar, Abdullah A. and Barry W. Alto. 2022. "Elephant Mosquito Toxorhynchites rutilus Coquillett, 1896 (Insecta: Diptera: Culicidae)," Ask IFAS EENY-787/IN1380. University of Florida.
Coin, Patrick, et al. 2004. "Species Toxorhynchites rutilus - Elephant Mosquito," Bugguide.net
Donald, Claire L., Padet Siriyasatien, and Alain Kohl. 2020. "Toxorhynchites Species: A Review of Current Knowledge," Insects 11(11): 747.
McAlister, Erica. 2017. The Secret Life of Flies. Buffalo: Firefly Books. 248 pp.
Ricciuti, Ed. 2019. "Meet the Mosquito With a Big Appetite - for Other Mosquitoes," Entomology Today.

Orthoptera Thursday: The Katydid's Menu

Carnivorous katydids? That might come as a shock, but in reality, many members of the order Orthoptera, which includes katydids, grasshoppers, and crickets, are omnivorous to at least some degree. This broad diet is one reason these insects are so successful. Let’s take a closer look at one subset of katydids in particular.

A female Orchelimum sp. meadow katydid.

Katydids are also known as longhorned grasshoppers, for their exceptionally long, thread-like antennae, in contrast to true grasshoppers that have shorter, thicker antennae. Katydids are in the family Tettigoniidae. Most katydids are green, brown, or gray in color, though tropical species can be stunningly colorful.

Meadow katydids and conehead katydids form the subfamily Conocephalinae. They are among the most abundant of orthopterans in the eastern United States and adjacent Canada. At this time of year they have reached maturity and are seeking mates. Taking a stroll through tall grass, especially in wetlands, lush meadows, or prairies will flush countless individuals.

A female conehead katdid, Neoconocephalus sp.

A substantial portion of the diet for these katydids is grass seeds, and they have mandibles (jaws) powerful enough to crack them. Conehead katydids are the largest, some members of the gens Neoconocephalus exceeding seven centimeters (nearly three inches). I can tell you from personal experience that you do not want to get bitten by one of them.

A male conehead katydid peers from dense grass.

Meadow katydids and coneheads also feed on forbs, defined as any flowering herbaceous plant that is not a grass, sedge, or rush. The insects feed on the leaves and flowers of those plants.

The impact of katydids on plant communities is not negligible. One study revealed that a population of three meadow katydid species turned nearly 16% of the biomass of a rush species (Juncus) into katydid biomass (Parsons and de la Cruz, 1980).. Damage to seeds developing in flowers resulted in a 30-50% decrease in in seed production of rushes and grasses, too.

A female lesser meadow katydid, Conocephalus sp., feeds herself a grass seed.

Watching a katydid eat is a delightful experience. They are surprisingly nimble, and will use their front tarsi (the “feet” on their front legs) like hands to direct the morsel into their mouths. It is very much like any mammal feeding itself, using its paws.

A male Orchelimum eating an acanoloniid planthopper.

Plant matter has relatively little protein and fat, so those compounds need to come from elsewhere for a katydid to prosper. Consequently, some species, especially the meadow katydids, have evolved to become opportunistic predators on other insects, especially if those insects are injured.

The insects usually encountered by katydids are other species that are herbivorous in the same habitats occupied by the katydids. This includes leafhoppers, planthoppers, and even smaller katydids.

A female Orchelimum feeding on a female smaller meadow katydid, Conocephalus sp. The victim had just mated.

Female katydids need extra protein to nourish the development of eggs, and they get a surprising assist from males. During copulation, the male delivers a sperm packet called a spermatophore. The spermatophore consists of the sperm container (ampulla) and a gelatinous mass called a spermatophylax. This is an expensive gift for the male to produce, but it is less likely that a female will mate again once she is provided this nutritious investment. This is especially true for larger meadow katydids, genus Orchelimum.

The spermatophylax consists of protein, water, some carbohydrates, but few lipids (fatty acids). The female consumes this after mating occurs, along with the rest of the spermatorphore, which protrudes from her genital tract after its insertion by the male.

A pair of meadow katydids, Orchelimum sp., just beginning to mate.

The spermatophore is perhaps one step away from sacrificing yourself entirely to your mate. Science weighs the concrete costs and benefits of such transactions, but perhaps something more meaningful is lost in the translation. The more we learn about the insect nervous system, the shorter the distance between “them” and “us.”

The jelly-like spermatophore forming where the pair are joined.

Sources:Gwynne, Darryl T. 2001. Katydids and Bush-Crickets: Reproductive Behavior and Evolution of the Tettigoniidae. Ithaca: Cornell University Press (Comstock Publishing Associates). 317 pp.
Parsons, K.A., and A.A. de la Cruz. 1980. “Energy flow and grazing behavior of conocephaline grasshoppers in a Juncus roemerianus marsh,” Ecology 61: 1045-1050.
Thornhill, Randy and John Alcock. 1983. The Evolution of Insect Mating Systems. Cambridge: Harvard University Press. 547 pp.

I Am Not a Scientist

It’s cute when someone mistakes me for a scientist, presumably because I have written books about insects, made public presentations, and am active on social media. There are occasions, though, where the confusion wastes the other party’s time, and for that I am truly apologetic. I am still a reliable source of factual information, but please allow me to set the record straight.

This post is prompted by an email exchange I had recently with a dear friend and colleague who truly is a scientist, seeking my help with a project.

Them: “I have a favor to ask….

For the past [few] years I have been conducting a long-term….survey at different nature preserves….in the hopes of trying to get a better idea of conservatisms of these insects….Ultimately I want to be able to look at a species list of insects found within a natural community or natural area and determine….which sites provide high quality critical habitat for plant community specialist insects, separate from the plant C values ranks.

The problem is few people are familiar with a wide diversity of insects. Most experts just know a particular family of insects….I have ranked all 371 taxa based on my field expertise. I'm teaming up with a dragonfly specialist for the statistical analysis. [They have] some experience with developing conservatism ranks for dragonflies and is trying to apply this to my data.

Would you be willing to take a look at the list and provide numerical ranking for the species you readily recognize? I know [specific region] isn't your main stomping ground, but you do know many of the more common species, and your ranks would be most helpful.

If you are interested in getting involved and reviewing our work for a future publication, and possibly coauthoring with us, we are open to that….My goal is to bring attention to the insects here in [specified state].

Let me know if you have any questions.

Thanks so much.”

Me: “I am flattered by the request, and would be willing to help....if I understood the assignment. I have no idea what a "C value" is. I could potentially rank them in terms of the frequency with which I see that particular genus or species on a particular plant. That can still vary significantly from one year to the next. This year, in our area, insect numbers are down significantly. I am not seeing many insects….

If there is a concrete definition of C values, then please provide it. I may or may not be able to assist. Math is my greatest weakness, and I never took statistics (not that it would even be useful given that I was in college in the early 1980s).

I am a writer and sci-comm professional, all else comes in no particular order after that.”

Them: “Yeah, don't ask me to explain statistics either. That's why I team up with the survey biologists.

As far as I know the concept of the C value (or coefficient of conservatism) came about in 1979 to reduce subjectivity in the evaluation of plant communities by placing the subjectivity up front. All plant (or other taxa) are assigned a numeric value that [provides] assessment natural quality repeatability.

In basic terms, ‘how likely is this taxa found in a high quality community?’….It's not just how common it is, though that is a factor as high quality (conservative) species are typically found only in rare habitats and thus are less likely to be encountered. The numbering is from 0-10. Almost all state-listed species are assigned a value of 10….A goldenrod soldier beetle (Chauliognathus pensylvanicus) might be a 1 or 2 as they are common [pretty much everywhere].

We also ask that you rate your confidence level 1 - 3 (3 being very confident in your rank and 1 being much less familiar with the species).

Does that help?”

Me: “Yes, that does help. I am not qualified to undertake that, being unfamiliar with [those] ecosystems at *that level*….I'm sorry, but I would potentially be doing more harm than good if I took a stab at this.

Sorry!”

Them: “….

The point is to ask. I realize it's specialized. If others are unable, then that's part of our argument - we get the best data we can. I don't know if any of this is possible but I'm going to keep at it. The more I do the more I learn.

Thanks”

Me: “My comment wasn't an indictment, apologies if it sounded that way.

You are vastly more capable than I am, and have much more experience in that kind of habitat. Maybe someone at [non-profit organization] can help?

Maybe I do not make it clear enough to anyone that I am not as much an entomologist as an ‘insect identifier.’"

Them: “I didn't take it that way. No worries.”

There is another aspect of my personality at play here. I am inherently lazy. Community science is hard work, with demanding and specific requirements for projects aimed at collecting data. That is not what interests me. I am all about recruiting potential community scientists by sharing fascinating facts and personal experiences. Heck, if I can get someone to put down the fly swatter in favor of a magnifying glass, mission accomplished.

I want to change the behavior of the average Joe or Jane who despises insects and wants them gone. Humanity as a whole, and the entire planet, for that matter, cannot survive the continued loss of biodiversity and insect abundance. More to the point, I can’t survive it. Exploring the natural world and finding insects is one of the few exercises keeping me reasonably sane, and giving me a sense of purpose. Without the “bugs,” I vanish, too.