The New Neotropical Companion

people can identify cockroaches easily (plate 16- 92), as

they routinely cohabit human dwellings, much to the

dismay of the primate occupants. But such an attitude

is wrong- headed. You ought to be willing to share with

them. Their evolutionary lineage reaches well back into

deep time. Cockroaches have resided on the planet

for over 300 million years, and they are a wonderful

evolutionary success story. They do not bite or sting, nor

do they carry vile diseases. So relax and enjoy them. You

might as well. In the Neotropics, at least, they are always

close by.

Cockroaches are oval in shape, are covered on the

dorsal side by a pair of large wings, and sport a pair of

very long antennae on the head. Excellent fliers and

basically nocturnal, they are often seen fluttering around

lights at night. They are remarkably fast runners and

have an uncanny ability to squeeze between floorboards

and into other tight places.

One of the most striking tropical species is the Giant

Cockroach (Blaberus giganteus). At full size, this insect

behemoth easily fills the palm of your hand and then

some. It lives in hollow trees and other reclusive places

during the day and scurries about in search of food at

night. Blaberus is a good cockroach mother. I came upon

one on the forest floor, near an outhouse (cockroaches

like outhouses) in Amazonian Peru. I noticed lots of odd

little white things around the animal. Closer inspection

revealed that the little white things were unpigmented

baby cockroaches. The adult was brooding, and was

very protective about getting the pale little animals

under the protection of her wings. With such devoted

parental care, it’s no wonder they have been around for

so many millions of years.

Harlequin Longhorn Beetle

There are many thousands of Neotropical coleopterans

(beetle biodiversity was discussed in chapter 9). Acrocinus

longimanus, commonly called the Harlequin Longhorn

Beetle (plate 16- 93), is both large (to 7.5 cm/ 3 in) and

colorful (complexly patterned in red, black, and yellow)

and sports very long antennae. Males have extremely

long and thick front legs, used during mating. Larvae live

inside bark, forming galleries inside the wood, and heavy

infestations may kill the tree. Adults inhabit a variety of

trees, including figs, and are strongly attracted to sap.

If you are fortunate enough to find one of these large

insects, look carefully under its thick outer wings (elytra).

Don’t worry; it won’t bite you, at least not to the degree

that you ought to care about it. Beneath the wings you can

usually find a tiny pseudoscorpion (not a real scorpion, so

don’t worry about being stung). The pseudoscorpion uses

the harlequin beetle as a host. The host gains no benefit

from the pseudoscorpion, but the little hitchhiker does no

harm, so this is an example of commensalism.

Rhinoceros and Hercules Beetles

These beetles, as the names imply, are formidable in size.

They are members of the Lamellicornia, a beetle group

that includes the scarab and stag beetles. The rhinoceros

beetles (Megasoma spp.; plate 16- 94) are scarabs named

for the long up- curved, hornlike projection possessed

by the males. Megasoma elephas, commonly called the

Elephant Beetle, is a huge and bulky rhinoceros beetle that

can exceed 8 cm (3 in) in length. It is mostly brownish,

its elytra (thick outer wings) covered by tiny hairs. The

combination of large size, long horns, and hairy surface

Plate 16- 93. The Harlequin Longhorn Beetle. Photo by James Plate 16- 94. Rhinoceros beetle, male. Photo by Gina Nichol.

Adams.

chapter 16 from monkeys to tarantulas: endless eccentricities 359