Tuesday, June 21, 2011

Mantidfly, Antlion, Fishfly, Lacewing and Dobsonfly ... Nerve-winged Insects

An uncommon insect that looks like a weird hybrid between a preying mantis and a wasp, and probably often overlooked because of its resemblance to the latter. This mantidfly is about 30 mm long; it looks like Climaciella brunnea, and as it's appearance suggests, the adult is predacious. The larvae are parasites of spiders. Mantidflies belong to the order Neuroptera (meaning
"net wings" or "nerve wings"), which also includes lacewings, ant lions, fishflies and dobsonflies.

Antlion larvae are known for their sand traps. This adult Brachynemurus abdominalis is getting ready to take flight, when at rest the wings are normally folded over the back in the manner of a moth or caddisfly. Antlion adults can be mistaken for a damselfly ...

... but a damselfly doesn't have long antennae like this.

Although much smaller the Lacewing bears a resemlance to its larger relatives, the Fishfly and the Dobsonfly. Lacewings are sometimes called stinkflies for the unpleasant smell they release in self-defense if they feel threatened. Adults feed on pollen and nectar, the larvae eat aphids.

Images of a couple of fishflies. When I took these photos I was uncertain if the antennae were different because these are a male and female of the same species, or two different kinds of fishfly. According to BugGuide.Net these are female and male Spring Fishflies (Chauliodes rastricornis); the head and pronotum have dark markings on a light background. Only the male of this species has the comb-like or pectinate antennae. The Summer Fishfly (Chauliodes pectinicornis) has pale markings on a darker background and both sexes possess the pectinate antennae.

Similar in appearance to the Fishfly but much larger is the Eastern Dobsonfly (Corydalus cornutus). The aquatic larvae, sometimes call hellgrammites, are the top insect predator in their little corner of the world; this one was a good 90 mm long.

The adult females retain the larval jaws and while they can give a really good bite if mishandled they are not venomous. As is often the case, they don't eat at all, the adult form living only long enough to reproduce. Males have long pincer-like mandibles: while giving them a fierce aspect the jaws are too long to exert any force and are harmless.

Here's a link to some images of a male Dobsonfly ... the insect that started this blog.