Archive | April, 2013

Orange Hoppers

26 Apr
Orange baby leafhoppers under a log.

Immature planthoppers hanging out in a fungal growth under a log.

I found these brightly colored insects tucked under a log in Arizona, where they appeared to be feeding on a growth of fluffy white material–perhaps fungi or mold.  These are immature planthoppers, members of the same group of tiny hopping green specks you sometimes run into in lawns or trees.  This was, for me, a pretty surprising place to encounter a hopper, so I looked around to see what else I could find out about these little fellows.

The lovely community over at BugGuide has tentatively identified these as members of the family Derbidae, based at least partially on the context I discovered them in.  While adult derbid hoppers, like most planthoppers, are sap suckers, the nymphs of some species feed on fungi, particularly in rotten logs.

Because these hoppers are immatures, their wings have not yet developed (you can see the developing wing buds on their backs).  Adult derbids typically have long, delicate wings for hoppers.  In fact, they are noted for gathering to perch under broad leaves, a behavior which may protect their fragile wings (U Del).

How to Build a Bunch of Different Formicaria

18 Apr

Since my “Ant Farms: How to Build Your Own Formicarium” page is one of my most visited articles, I’ve created a page to compile some different ant rearing/formicaria designs that I have seen or used.

Please check it out!

Acrobat ants in a flat plaster nest.

Acrobat ants in a flat plaster nest.

Carpenter ants checking out air holes at the top of the stacked colony.

Carpenter ants checking out air holes at the top of a colony.

Monomorium minimum ants in with a tube ant nest.

Monomorium ants with a tube nest.

Rover ants and queen with brood in plaster nest.

Rover ants and queen with brood in plaster nest.

See more at:

Ant Farms: More formicaria designs

and see also:

Ant Farms: How to Build Your Own Formicarium

Techniques

Fluffy Caterpillars and Latin Names

12 Apr
Spiky black yellow red white caterpillars with tussocks.

Colorful silkworm caterpillars feeding on vegetation.

These coloful and spiky fellows are silkworms of the species Apatelodes pudefacta.  The large, rather fluffy and spiky-winged adults are often mistaken for hawkmoths, and the tufted caterpillars can resemble tussock moth or dagger moth juveniles.  In fact, the genus name “Apatelodes” literally means “looks like Apatela,” a reference to the old genus name for dagger moths.  (“Apatela” later became “Acronicta.”)

This particular species gets two obscure references in its name.  The species name “pudefacta” means “ashamed” and is likely a play on the related species “diffidens” meaning “diffident.”

The moral of the story is that scientists cannot be trusted to name things in non-confusing ways.

Fuzzy black yellow red white caterpillar with tussocks

Dinoponera: Giant Killer Ants from the Amazon

5 Apr
Giant ant with big jaws.

Head and jaws of Dinoponera gigantea. (Photo courtesy Israel Del Toro)

Today’s post is about Dinoponera, which is a really freaking cool genus of ants, containing some of the largest species of ants in the world.  It is brought to you in recognition of my labmate Paul Lenhart’s new paper revising the genus, and also the following conversation:

Paul: What would I have to do to convince you to shamelessly plug my new paper on your blog?

Alison: Oh, okay, I can do that.  Send me some cool pictures.

Collin: At least ask for money.

Giant dinoponerine ant with stinger.

Dinoponera quadriceps with stinger visible. (Photo courtesy Israel Del Toro)

So some cool things about these South American ants.  The name Dinoponera translates roughly to “terrible devil,” or possibly “terrible painful evil thing.”  As I mentioned, Dinoponera can get quite large: Dinoponera gigantea workers get up to 3.6 cm, almost an inch and a half in length.  The stings and venom of these extremely predaceous ants are very strong and have been suggested to possibly be more painful than those of the infamous “bullet ants” (whose sting, according to popular lore, is like getting hit with a bullet).

New species of giant dinoponerine ant.

Newly described species, Dinoponera hispida. (Photo courtesy Israel Del Toro)

Dinoponera is one of a few ponerine ants which has lost the morphologically distinct queen caste.  Instead, to quote Paul directly: “one of the younger females becomes dominant, beats the shit out of the other ants, and her ovaries swell up and she becomes queen.”

Because this status is flexible, she is sometimes also referred to as the alpha female.  If she dies the process begins again, and another worker can step up to fill her place.  New colonies are formed when one of the beta females absconds with a cohort of workers, a process called fission.  Average colony size varies by species, and ranges from as small as about 10 workers to as large (if it can be called large) as 120 workers.

Giant winged dinoponerine male ant.

Winged male sexual of Dinoponera gigantea.  The genitalia have been removed for analysis.  (Photo courtesy Israel Del Toro)

The males are winged, but the females, since they are not a distinct sexual caste, are wingless.  Instead they wait at the entrance of the nest and mate with visiting males.  This is when things take a turn.  After mating, the female chews through the male’s gaster (basically his belly) to release herself. The male’s genitalia is left inside her.  This may function as a temporary mating plug, preventing her from mating with other males.

Nature! I can’t make this stuff up.

Sawtooth "chainsaw penis" of dinoponerine ant

The penis valve of newly described species, Dinoponera snellingi. (Photo courtesy Paul Lenhart)

It is possible the genitalia of the males are partially adapted for this “plug” purpose, as many have a barbed, sawtooth edge. In fact, one of the new species Paul and his coauthors described is most easily recognized by what Paul described as a “chainsaw penis,” a particularly strongly lobed “penis valve” with teeth running the length.  The newly described species is named Dinoponera snellingi, in honor of the late renowned entomologist and colleague, Roy Snelling.  I have no further comment on this subject.

Roy Snelling

The inimitable Roy Snelling.

One of the other new species, Dinoponera hispida, was described from specimens that were all collected in a single region of northern Brazil, called Tucuruí.  The only known location of this species has since been completely flooded, due to the construction of the Tucuruí dam, making it possible that this species became extinct before it was ever described.

Many insect boxes in the shelves of an insect collection.

The LA County Museum Holdings. (Photo courtesy P. Lenhart)

To write this paper, Paul and his coauthors looked at over 350 specimens and sought loans from collections all over the new world, as well as places like Germany and Italy, where holotypes (world representative specimens of the species) were preserved.  He also visited Ecuador and Argentina.  Paul said it was really cool to see types collected as far back as the 1800s.  On the other hand after years of work and thousands of person hours spent on this project he has still never seen a live Dinoponera ant.

Science!

Scientist observing ant taxonomy.

The life of a taxonomist: Coauthor Dr. Bill Mackay observing Dinoponera specimens at California Academy of Science. (Photo courtesy P. Lenhart)

Did I mention Paul has a new paper out?

Fire Ant Mating Flight

1 Apr

Following up the post from last Friday, here’s is some extremely dramatic and engaging cell phone footage of a mating flight of fire ants on a stump outside our lab.

Video courtesy Collin McMichael.  And yes, that is us having an engaging discussion about why this colony has not succumbed to our regular fire ant harvests:

Alison:  That is quite the flight.

Collin: I’m taking a video.

Alison: I guess when you nest in the base of a stump nobody messes with you.

Collin: Nope, no one digs you up.

Alison: Yeah. Can’t get mowed.

Gripping stuff.

PS:  I have updated my “Things That Are Not Fire Ants” page with 4 new images and 14 new pest control companies.  Clearly I am enjoying the Google “search by image” tool.